gdbserver: rename source files to .cc

For the same reasons outlined in the previous patch, this patch renames
gdbserver source files to .cc.

I have moved the "-x c++" switch to only those rules that require it.

gdbserver/ChangeLog:

	* Makefile.in: Rename source files from .c to .cc.
	* %.c: Rename to %.cc.
	* configure.ac: Rename server.c to server.cc.
	* configure: Re-generate.

1 files changed, 7473 insertions, 0 deletions

diff --git a/gdbserver/tracepoint.cc b/gdbserver/tracepoint.cc
new file mode 100644
index 00000000000..bbca48b2efd
--- /dev/null
+++ b/gdbserver/tracepoint.cc
@@ -0,0 +1,7473 @@
+/* Tracepoint code for remote server for GDB.
+   Copyright (C) 2009-2020 Free Software Foundation, Inc.
+
+   This file is part of GDB.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include "server.h"
+#include "tracepoint.h"
+#include "gdbthread.h"
+#include "gdbsupport/rsp-low.h"
+
+#include <ctype.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <chrono>
+#include <inttypes.h>
+#include "ax.h"
+#include "tdesc.h"
+
+#define IPA_SYM_STRUCT_NAME ipa_sym_addresses
+#include "gdbsupport/agent.h"
+
+#define DEFAULT_TRACE_BUFFER_SIZE 5242880 /* 5*1024*1024 */
+
+/* This file is built for both GDBserver, and the in-process
+   agent (IPA), a shared library that includes a tracing agent that is
+   loaded by the inferior to support fast tracepoints.  Fast
+   tracepoints (or more accurately, jump based tracepoints) are
+   implemented by patching the tracepoint location with a jump into a
+   small trampoline function whose job is to save the register state,
+   call the in-process tracing agent, and then execute the original
+   instruction that was under the tracepoint jump (possibly adjusted,
+   if PC-relative, or some such).
+
+   The current synchronization design is pull based.  That means,
+   GDBserver does most of the work, by peeking/poking at the inferior
+   agent's memory directly for downloading tracepoint and associated
+   objects, and for uploading trace frames.  Whenever the IPA needs
+   something from GDBserver (trace buffer is full, tracing stopped for
+   some reason, etc.) the IPA calls a corresponding hook function
+   where GDBserver has placed a breakpoint.
+
+   Each of the agents has its own trace buffer.  When browsing the
+   trace frames built from slow and fast tracepoints from GDB (tfind
+   mode), there's no guarantee the user is seeing the trace frames in
+   strict chronological creation order, although, GDBserver tries to
+   keep the order relatively reasonable, by syncing the trace buffers
+   at appropriate times.
+
+*/
+
+#ifdef IN_PROCESS_AGENT
+
+static void trace_vdebug (const char *, ...) ATTRIBUTE_PRINTF (1, 2);
+
+static void
+trace_vdebug (const char *fmt, ...)
+{
+  char buf[1024];
+  va_list ap;
+
+  va_start (ap, fmt);
+  vsprintf (buf, fmt, ap);
+  fprintf (stderr, PROG "/tracepoint: %s\n", buf);
+  va_end (ap);
+}
+
+#define trace_debug_1(level, fmt, args...)	\
+  do {						\
+    if (level <= debug_threads)		\
+      trace_vdebug ((fmt), ##args);		\
+  } while (0)
+
+#else
+
+#define trace_debug_1(level, fmt, args...)	\
+  do {						\
+    if (level <= debug_threads)			\
+      {						\
+	debug_printf ((fmt), ##args);		\
+	debug_printf ("\n");			\
+      }						\
+  } while (0)
+
+#endif
+
+#define trace_debug(FMT, args...)		\
+  trace_debug_1 (1, FMT, ##args)
+
+/* Prefix exported symbols, for good citizenship.  All the symbols
+   that need exporting are defined in this module.  Note that all
+   these symbols must be tagged with IP_AGENT_EXPORT_*.  */
+#ifdef IN_PROCESS_AGENT
+# define gdb_tp_heap_buffer IPA_SYM_EXPORTED_NAME (gdb_tp_heap_buffer)
+# define gdb_jump_pad_buffer IPA_SYM_EXPORTED_NAME (gdb_jump_pad_buffer)
+# define gdb_jump_pad_buffer_end IPA_SYM_EXPORTED_NAME (gdb_jump_pad_buffer_end)
+# define gdb_trampoline_buffer IPA_SYM_EXPORTED_NAME (gdb_trampoline_buffer)
+# define gdb_trampoline_buffer_end IPA_SYM_EXPORTED_NAME (gdb_trampoline_buffer_end)
+# define gdb_trampoline_buffer_error IPA_SYM_EXPORTED_NAME (gdb_trampoline_buffer_error)
+# define collecting IPA_SYM_EXPORTED_NAME (collecting)
+# define gdb_collect_ptr IPA_SYM_EXPORTED_NAME (gdb_collect_ptr)
+# define stop_tracing IPA_SYM_EXPORTED_NAME (stop_tracing)
+# define flush_trace_buffer IPA_SYM_EXPORTED_NAME (flush_trace_buffer)
+# define about_to_request_buffer_space IPA_SYM_EXPORTED_NAME (about_to_request_buffer_space)
+# define trace_buffer_is_full IPA_SYM_EXPORTED_NAME (trace_buffer_is_full)
+# define stopping_tracepoint IPA_SYM_EXPORTED_NAME (stopping_tracepoint)
+# define expr_eval_result IPA_SYM_EXPORTED_NAME (expr_eval_result)
+# define error_tracepoint IPA_SYM_EXPORTED_NAME (error_tracepoint)
+# define tracepoints IPA_SYM_EXPORTED_NAME (tracepoints)
+# define tracing IPA_SYM_EXPORTED_NAME (tracing)
+# define trace_buffer_ctrl IPA_SYM_EXPORTED_NAME (trace_buffer_ctrl)
+# define trace_buffer_ctrl_curr IPA_SYM_EXPORTED_NAME (trace_buffer_ctrl_curr)
+# define trace_buffer_lo IPA_SYM_EXPORTED_NAME (trace_buffer_lo)
+# define trace_buffer_hi IPA_SYM_EXPORTED_NAME (trace_buffer_hi)
+# define traceframe_read_count IPA_SYM_EXPORTED_NAME (traceframe_read_count)
+# define traceframe_write_count IPA_SYM_EXPORTED_NAME (traceframe_write_count)
+# define traceframes_created IPA_SYM_EXPORTED_NAME (traceframes_created)
+# define trace_state_variables IPA_SYM_EXPORTED_NAME (trace_state_variables)
+# define get_raw_reg_ptr IPA_SYM_EXPORTED_NAME (get_raw_reg_ptr)
+# define get_trace_state_variable_value_ptr \
+  IPA_SYM_EXPORTED_NAME (get_trace_state_variable_value_ptr)
+# define set_trace_state_variable_value_ptr \
+  IPA_SYM_EXPORTED_NAME (set_trace_state_variable_value_ptr)
+# define ust_loaded IPA_SYM_EXPORTED_NAME (ust_loaded)
+# define helper_thread_id IPA_SYM_EXPORTED_NAME (helper_thread_id)
+# define cmd_buf IPA_SYM_EXPORTED_NAME (cmd_buf)
+# define ipa_tdesc_idx IPA_SYM_EXPORTED_NAME (ipa_tdesc_idx)
+#endif
+
+#ifndef IN_PROCESS_AGENT
+
+/* Addresses of in-process agent's symbols GDBserver cares about.  */
+
+struct ipa_sym_addresses
+{
+  CORE_ADDR addr_gdb_tp_heap_buffer;
+  CORE_ADDR addr_gdb_jump_pad_buffer;
+  CORE_ADDR addr_gdb_jump_pad_buffer_end;
+  CORE_ADDR addr_gdb_trampoline_buffer;
+  CORE_ADDR addr_gdb_trampoline_buffer_end;
+  CORE_ADDR addr_gdb_trampoline_buffer_error;
+  CORE_ADDR addr_collecting;
+  CORE_ADDR addr_gdb_collect_ptr;
+  CORE_ADDR addr_stop_tracing;
+  CORE_ADDR addr_flush_trace_buffer;
+  CORE_ADDR addr_about_to_request_buffer_space;
+  CORE_ADDR addr_trace_buffer_is_full;
+  CORE_ADDR addr_stopping_tracepoint;
+  CORE_ADDR addr_expr_eval_result;
+  CORE_ADDR addr_error_tracepoint;
+  CORE_ADDR addr_tracepoints;
+  CORE_ADDR addr_tracing;
+  CORE_ADDR addr_trace_buffer_ctrl;
+  CORE_ADDR addr_trace_buffer_ctrl_curr;
+  CORE_ADDR addr_trace_buffer_lo;
+  CORE_ADDR addr_trace_buffer_hi;
+  CORE_ADDR addr_traceframe_read_count;
+  CORE_ADDR addr_traceframe_write_count;
+  CORE_ADDR addr_traceframes_created;
+  CORE_ADDR addr_trace_state_variables;
+  CORE_ADDR addr_get_raw_reg_ptr;
+  CORE_ADDR addr_get_trace_state_variable_value_ptr;
+  CORE_ADDR addr_set_trace_state_variable_value_ptr;
+  CORE_ADDR addr_ust_loaded;
+  CORE_ADDR addr_ipa_tdesc_idx;
+};
+
+static struct
+{
+  const char *name;
+  int offset;
+} symbol_list[] = {
+  IPA_SYM(gdb_tp_heap_buffer),
+  IPA_SYM(gdb_jump_pad_buffer),
+  IPA_SYM(gdb_jump_pad_buffer_end),
+  IPA_SYM(gdb_trampoline_buffer),
+  IPA_SYM(gdb_trampoline_buffer_end),
+  IPA_SYM(gdb_trampoline_buffer_error),
+  IPA_SYM(collecting),
+  IPA_SYM(gdb_collect_ptr),
+  IPA_SYM(stop_tracing),
+  IPA_SYM(flush_trace_buffer),
+  IPA_SYM(about_to_request_buffer_space),
+  IPA_SYM(trace_buffer_is_full),
+  IPA_SYM(stopping_tracepoint),
+  IPA_SYM(expr_eval_result),
+  IPA_SYM(error_tracepoint),
+  IPA_SYM(tracepoints),
+  IPA_SYM(tracing),
+  IPA_SYM(trace_buffer_ctrl),
+  IPA_SYM(trace_buffer_ctrl_curr),
+  IPA_SYM(trace_buffer_lo),
+  IPA_SYM(trace_buffer_hi),
+  IPA_SYM(traceframe_read_count),
+  IPA_SYM(traceframe_write_count),
+  IPA_SYM(traceframes_created),
+  IPA_SYM(trace_state_variables),
+  IPA_SYM(get_raw_reg_ptr),
+  IPA_SYM(get_trace_state_variable_value_ptr),
+  IPA_SYM(set_trace_state_variable_value_ptr),
+  IPA_SYM(ust_loaded),
+  IPA_SYM(ipa_tdesc_idx),
+};
+
+static struct ipa_sym_addresses ipa_sym_addrs;
+
+static int read_inferior_integer (CORE_ADDR symaddr, int *val);
+
+/* Returns true if both the in-process agent library and the static
+   tracepoints libraries are loaded in the inferior, and agent has
+   capability on static tracepoints.  */
+
+static int
+in_process_agent_supports_ust (void)
+{
+  int loaded = 0;
+
+  if (!agent_loaded_p ())
+    {
+      warning ("In-process agent not loaded");
+      return 0;
+    }
+
+  if (agent_capability_check (AGENT_CAPA_STATIC_TRACE))
+    {
+      /* Agent understands static tracepoint, then check whether UST is in
+	 fact loaded in the inferior.  */
+      if (read_inferior_integer (ipa_sym_addrs.addr_ust_loaded, &loaded))
+	{
+	  warning ("Error reading ust_loaded in lib");
+	  return 0;
+	}
+
+      return loaded;
+    }
+  else
+    return 0;
+}
+
+static void
+write_e_ipa_not_loaded (char *buffer)
+{
+  sprintf (buffer,
+	   "E.In-process agent library not loaded in process.  "
+	   "Fast and static tracepoints unavailable.");
+}
+
+/* Write an error to BUFFER indicating that UST isn't loaded in the
+   inferior.  */
+
+static void
+write_e_ust_not_loaded (char *buffer)
+{
+#ifdef HAVE_UST
+  sprintf (buffer,
+	   "E.UST library not loaded in process.  "
+	   "Static tracepoints unavailable.");
+#else
+  sprintf (buffer, "E.GDBserver was built without static tracepoints support");
+#endif
+}
+
+/* If the in-process agent library isn't loaded in the inferior, write
+   an error to BUFFER, and return 1.  Otherwise, return 0.  */
+
+static int
+maybe_write_ipa_not_loaded (char *buffer)
+{
+  if (!agent_loaded_p ())
+    {
+      write_e_ipa_not_loaded (buffer);
+      return 1;
+    }
+  return 0;
+}
+
+/* If the in-process agent library and the ust (static tracepoints)
+   library aren't loaded in the inferior, write an error to BUFFER,
+   and return 1.  Otherwise, return 0.  */
+
+static int
+maybe_write_ipa_ust_not_loaded (char *buffer)
+{
+  if (!agent_loaded_p ())
+    {
+      write_e_ipa_not_loaded (buffer);
+      return 1;
+    }
+  else if (!in_process_agent_supports_ust ())
+    {
+      write_e_ust_not_loaded (buffer);
+      return 1;
+    }
+  return 0;
+}
+
+/* Cache all future symbols that the tracepoints module might request.
+   We can not request symbols at arbitrary states in the remote
+   protocol, only when the client tells us that new symbols are
+   available.  So when we load the in-process library, make sure to
+   check the entire list.  */
+
+void
+tracepoint_look_up_symbols (void)
+{
+  int i;
+
+  if (agent_loaded_p ())
+    return;
+
+  for (i = 0; i < sizeof (symbol_list) / sizeof (symbol_list[0]); i++)
+    {
+      CORE_ADDR *addrp =
+	(CORE_ADDR *) ((char *) &ipa_sym_addrs + symbol_list[i].offset);
+
+      if (look_up_one_symbol (symbol_list[i].name, addrp, 1) == 0)
+	{
+	  if (debug_threads)
+	    debug_printf ("symbol `%s' not found\n", symbol_list[i].name);
+	  return;
+	}
+    }
+
+  agent_look_up_symbols (NULL);
+}
+
+#endif
+
+/* GDBserver places a breakpoint on the IPA's version (which is a nop)
+   of the "stop_tracing" function.  When this breakpoint is hit,
+   tracing stopped in the IPA for some reason.  E.g., due to
+   tracepoint reaching the pass count, hitting conditional expression
+   evaluation error, etc.
+
+   The IPA's trace buffer is never in circular tracing mode: instead,
+   GDBserver's is, and whenever the in-process buffer fills, it calls
+   "flush_trace_buffer", which triggers an internal breakpoint.
+   GDBserver reacts to this breakpoint by pulling the meanwhile
+   collected data.  Old frames discarding is always handled on the
+   GDBserver side.  */
+
+#ifdef IN_PROCESS_AGENT
+int
+read_inferior_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
+{
+  memcpy (myaddr, (void *) (uintptr_t) memaddr, len);
+  return 0;
+}
+
+/* Call this in the functions where GDBserver places a breakpoint, so
+   that the compiler doesn't try to be clever and skip calling the
+   function at all.  This is necessary, even if we tell the compiler
+   to not inline said functions.  */
+
+#if defined(__GNUC__)
+#  define UNKNOWN_SIDE_EFFECTS() asm ("")
+#else
+#  define UNKNOWN_SIDE_EFFECTS() do {} while (0)
+#endif
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC void stop_tracing (void);
+
+IP_AGENT_EXPORT_FUNC void
+stop_tracing (void)
+{
+  /* GDBserver places breakpoint here.  */
+  UNKNOWN_SIDE_EFFECTS();
+}
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC void flush_trace_buffer (void);
+
+IP_AGENT_EXPORT_FUNC void
+flush_trace_buffer (void)
+{
+  /* GDBserver places breakpoint here.  */
+  UNKNOWN_SIDE_EFFECTS();
+}
+
+#endif
+
+#ifndef IN_PROCESS_AGENT
+static int
+tracepoint_handler (CORE_ADDR address)
+{
+  trace_debug ("tracepoint_handler: tracepoint at 0x%s hit",
+	       paddress (address));
+  return 0;
+}
+
+/* Breakpoint at "stop_tracing" in the inferior lib.  */
+struct breakpoint *stop_tracing_bkpt;
+static int stop_tracing_handler (CORE_ADDR);
+
+/* Breakpoint at "flush_trace_buffer" in the inferior lib.  */
+struct breakpoint *flush_trace_buffer_bkpt;
+static int flush_trace_buffer_handler (CORE_ADDR);
+
+static void download_trace_state_variables (void);
+static void upload_fast_traceframes (void);
+
+static int run_inferior_command (char *cmd, int len);
+
+static int
+read_inferior_integer (CORE_ADDR symaddr, int *val)
+{
+  return read_inferior_memory (symaddr, (unsigned char *) val,
+			       sizeof (*val));
+}
+
+struct tracepoint;
+static int tracepoint_send_agent (struct tracepoint *tpoint);
+
+static int
+read_inferior_uinteger (CORE_ADDR symaddr, unsigned int *val)
+{
+  return read_inferior_memory (symaddr, (unsigned char *) val,
+			       sizeof (*val));
+}
+
+static int
+read_inferior_data_pointer (CORE_ADDR symaddr, CORE_ADDR *val)
+{
+  void *pval = (void *) (uintptr_t) val;
+  int ret;
+
+  ret = read_inferior_memory (symaddr, (unsigned char *) &pval, sizeof (pval));
+  *val = (uintptr_t) pval;
+  return ret;
+}
+
+static int
+write_inferior_data_pointer (CORE_ADDR symaddr, CORE_ADDR val)
+{
+  void *pval = (void *) (uintptr_t) val;
+  return target_write_memory (symaddr,
+				(unsigned char *) &pval, sizeof (pval));
+}
+
+static int
+write_inferior_integer (CORE_ADDR symaddr, int val)
+{
+  return target_write_memory (symaddr, (unsigned char *) &val, sizeof (val));
+}
+
+static int
+write_inferior_int8 (CORE_ADDR symaddr, int8_t val)
+{
+  return target_write_memory (symaddr, (unsigned char *) &val, sizeof (val));
+}
+
+static int
+write_inferior_uinteger (CORE_ADDR symaddr, unsigned int val)
+{
+  return target_write_memory (symaddr, (unsigned char *) &val, sizeof (val));
+}
+
+static CORE_ADDR target_malloc (ULONGEST size);
+
+#define COPY_FIELD_TO_BUF(BUF, OBJ, FIELD)	\
+  do {							\
+    memcpy (BUF, &(OBJ)->FIELD, sizeof ((OBJ)->FIELD)); \
+    BUF += sizeof ((OBJ)->FIELD);			\
+  } while (0)
+
+#endif
+
+/* Base action.  Concrete actions inherit this.  */
+
+struct tracepoint_action
+{
+  char type;
+};
+
+/* An 'M' (collect memory) action.  */
+struct collect_memory_action
+{
+  struct tracepoint_action base;
+
+  ULONGEST addr;
+  ULONGEST len;
+  int32_t basereg;
+};
+
+/* An 'R' (collect registers) action.  */
+
+struct collect_registers_action
+{
+  struct tracepoint_action base;
+};
+
+/* An 'X' (evaluate expression) action.  */
+
+struct eval_expr_action
+{
+  struct tracepoint_action base;
+
+  struct agent_expr *expr;
+};
+
+/* An 'L' (collect static trace data) action.  */
+struct collect_static_trace_data_action
+{
+  struct tracepoint_action base;
+};
+
+#ifndef IN_PROCESS_AGENT
+static CORE_ADDR
+m_tracepoint_action_download (const struct tracepoint_action *action)
+{
+  CORE_ADDR ipa_action = target_malloc (sizeof (struct collect_memory_action));
+
+  target_write_memory (ipa_action, (unsigned char *) action,
+			 sizeof (struct collect_memory_action));
+
+  return ipa_action;
+}
+static char *
+m_tracepoint_action_send (char *buffer, const struct tracepoint_action *action)
+{
+  struct collect_memory_action *maction
+    = (struct collect_memory_action *) action;
+
+  COPY_FIELD_TO_BUF (buffer, maction, addr);
+  COPY_FIELD_TO_BUF (buffer, maction, len);
+  COPY_FIELD_TO_BUF (buffer, maction, basereg);
+
+  return buffer;
+}
+
+static CORE_ADDR
+r_tracepoint_action_download (const struct tracepoint_action *action)
+{
+  CORE_ADDR ipa_action = target_malloc (sizeof (struct collect_registers_action));
+
+  target_write_memory (ipa_action, (unsigned char *) action,
+			 sizeof (struct collect_registers_action));
+
+  return ipa_action;
+}
+
+static char *
+r_tracepoint_action_send (char *buffer, const struct tracepoint_action *action)
+{
+  return buffer;
+}
+
+static CORE_ADDR download_agent_expr (struct agent_expr *expr);
+
+static CORE_ADDR
+x_tracepoint_action_download (const struct tracepoint_action *action)
+{
+  CORE_ADDR ipa_action = target_malloc (sizeof (struct eval_expr_action));
+  CORE_ADDR expr;
+
+  target_write_memory (ipa_action, (unsigned char *) action,
+			 sizeof (struct eval_expr_action));
+  expr = download_agent_expr (((struct eval_expr_action *) action)->expr);
+  write_inferior_data_pointer (ipa_action
+			       + offsetof (struct eval_expr_action, expr),
+			       expr);
+
+  return ipa_action;
+}
+
+/* Copy agent expression AEXPR to buffer pointed by P.  If AEXPR is NULL,
+   copy 0 to P.  Return updated header of buffer.  */
+
+static char *
+agent_expr_send (char *p, const struct agent_expr *aexpr)
+{
+  /* Copy the length of condition first, and then copy its
+     content.  */
+  if (aexpr == NULL)
+    {
+      memset (p, 0, 4);
+      p += 4;
+    }
+  else
+    {
+      memcpy (p, &aexpr->length, 4);
+      p +=4;
+
+      memcpy (p, aexpr->bytes, aexpr->length);
+      p += aexpr->length;
+    }
+  return p;
+}
+
+static char *
+x_tracepoint_action_send ( char *buffer, const struct tracepoint_action *action)
+{
+  struct eval_expr_action *eaction = (struct eval_expr_action *) action;
+
+  return agent_expr_send (buffer, eaction->expr);
+}
+
+static CORE_ADDR
+l_tracepoint_action_download (const struct tracepoint_action *action)
+{
+  CORE_ADDR ipa_action
+    = target_malloc (sizeof (struct collect_static_trace_data_action));
+
+  target_write_memory (ipa_action, (unsigned char *) action,
+			 sizeof (struct collect_static_trace_data_action));
+
+  return ipa_action;
+}
+
+static char *
+l_tracepoint_action_send (char *buffer, const struct tracepoint_action *action)
+{
+  return buffer;
+}
+
+static char *
+tracepoint_action_send (char *buffer, const struct tracepoint_action *action)
+{
+  switch (action->type)
+    {
+    case 'M':
+      return m_tracepoint_action_send (buffer, action);
+    case 'R':
+      return r_tracepoint_action_send (buffer, action);
+    case 'X':
+      return x_tracepoint_action_send (buffer, action);
+    case 'L':
+      return l_tracepoint_action_send (buffer, action);
+    }
+  error ("Unknown trace action '%c'.", action->type);
+}
+
+static CORE_ADDR
+tracepoint_action_download (const struct tracepoint_action *action)
+{
+  switch (action->type)
+    {
+    case 'M':
+      return m_tracepoint_action_download (action);
+    case 'R':
+      return r_tracepoint_action_download (action);
+    case 'X':
+      return x_tracepoint_action_download (action);
+    case 'L':
+      return l_tracepoint_action_download (action);
+    }
+  error ("Unknown trace action '%c'.", action->type);
+}
+#endif
+
+/* This structure describes a piece of the source-level definition of
+   the tracepoint.  The contents are not interpreted by the target,
+   but preserved verbatim for uploading upon reconnection.  */
+
+struct source_string
+{
+  /* The type of string, such as "cond" for a conditional.  */
+  char *type;
+
+  /* The source-level string itself.  For the sake of target
+     debugging, we store it in plaintext, even though it is always
+     transmitted in hex.  */
+  char *str;
+
+  /* Link to the next one in the list.  We link them in the order
+     received, in case some make up an ordered list of commands or
+     some such.  */
+  struct source_string *next;
+};
+
+enum tracepoint_type
+{
+  /* Trap based tracepoint.  */
+  trap_tracepoint,
+
+  /* A fast tracepoint implemented with a jump instead of a trap.  */
+  fast_tracepoint,
+
+  /* A static tracepoint, implemented by a program call into a tracing
+     library.  */
+  static_tracepoint
+};
+
+struct tracepoint_hit_ctx;
+
+typedef enum eval_result_type (*condfn) (unsigned char *,
+					 ULONGEST *);
+
+/* The definition of a tracepoint.  */
+
+/* Tracepoints may have multiple locations, each at a different
+   address.  This can occur with optimizations, template
+   instantiation, etc.  Since the locations may be in different
+   scopes, the conditions and actions may be different for each
+   location.  Our target version of tracepoints is more like GDB's
+   notion of "breakpoint locations", but we have almost nothing that
+   is not per-location, so we bother having two kinds of objects.  The
+   key consequence is that numbers are not unique, and that it takes
+   both number and address to identify a tracepoint uniquely.  */
+
+struct tracepoint
+{
+  /* The number of the tracepoint, as specified by GDB.  Several
+     tracepoint objects here may share a number.  */
+  uint32_t number;
+
+  /* Address at which the tracepoint is supposed to trigger.  Several
+     tracepoints may share an address.  */
+  CORE_ADDR address;
+
+  /* Tracepoint type.  */
+  enum tracepoint_type type;
+
+  /* True if the tracepoint is currently enabled.  */
+  int8_t enabled;
+
+  /* The number of single steps that will be performed after each
+     tracepoint hit.  */
+  uint64_t step_count;
+
+  /* The number of times the tracepoint may be hit before it will
+     terminate the entire tracing run.  */
+  uint64_t pass_count;
+
+  /* Pointer to the agent expression that is the tracepoint's
+     conditional, or NULL if the tracepoint is unconditional.  */
+  struct agent_expr *cond;
+
+  /* The list of actions to take when the tracepoint triggers.  */
+  uint32_t numactions;
+  struct tracepoint_action **actions;
+
+  /* Count of the times we've hit this tracepoint during the run.
+     Note that while-stepping steps are not counted as "hits".  */
+  uint64_t hit_count;
+
+  /* Cached sum of the sizes of traceframes created by this point.  */
+  uint64_t traceframe_usage;
+
+  CORE_ADDR compiled_cond;
+
+  /* Link to the next tracepoint in the list.  */
+  struct tracepoint *next;
+
+#ifndef IN_PROCESS_AGENT
+  /* The list of actions to take when the tracepoint triggers, in
+     string/packet form.  */
+  char **actions_str;
+
+  /* The collection of strings that describe the tracepoint as it was
+     entered into GDB.  These are not used by the target, but are
+     reported back to GDB upon reconnection.  */
+  struct source_string *source_strings;
+
+  /* The number of bytes displaced by fast tracepoints. It may subsume
+     multiple instructions, for multi-byte fast tracepoints.  This
+     field is only valid for fast tracepoints.  */
+  uint32_t orig_size;
+
+  /* Only for fast tracepoints.  */
+  CORE_ADDR obj_addr_on_target;
+
+  /* Address range where the original instruction under a fast
+     tracepoint was relocated to.  (_end is actually one byte past
+     the end).  */
+  CORE_ADDR adjusted_insn_addr;
+  CORE_ADDR adjusted_insn_addr_end;
+
+  /* The address range of the piece of the jump pad buffer that was
+     assigned to this fast tracepoint.  (_end is actually one byte
+     past the end).*/
+  CORE_ADDR jump_pad;
+  CORE_ADDR jump_pad_end;
+
+  /* The address range of the piece of the trampoline buffer that was
+     assigned to this fast tracepoint.  (_end is actually one byte
+     past the end).  */
+  CORE_ADDR trampoline;
+  CORE_ADDR trampoline_end;
+
+  /* The list of actions to take while in a stepping loop.  These
+     fields are only valid for patch-based tracepoints.  */
+  int num_step_actions;
+  struct tracepoint_action **step_actions;
+  /* Same, but in string/packet form.  */
+  char **step_actions_str;
+
+  /* Handle returned by the breakpoint or tracepoint module when we
+     inserted the trap or jump, or hooked into a static tracepoint.
+     NULL if we haven't inserted it yet.  */
+  void *handle;
+#endif
+
+};
+
+#ifndef IN_PROCESS_AGENT
+
+/* Given `while-stepping', a thread may be collecting data for more
+   than one tracepoint simultaneously.  On the other hand, the same
+   tracepoint with a while-stepping action may be hit by more than one
+   thread simultaneously (but not quite, each thread could be handling
+   a different step).  Each thread holds a list of these objects,
+   representing the current step of each while-stepping action being
+   collected.  */
+
+struct wstep_state
+{
+  struct wstep_state *next;
+
+  /* The tracepoint number.  */
+  int tp_number;
+  /* The tracepoint's address.  */
+  CORE_ADDR tp_address;
+
+  /* The number of the current step in this 'while-stepping'
+     action.  */
+  long current_step;
+};
+
+#endif
+
+EXTERN_C_PUSH
+
+/* The linked list of all tracepoints.  Marked explicitly as used as
+   the in-process library doesn't use it for the fast tracepoints
+   support.  */
+IP_AGENT_EXPORT_VAR struct tracepoint *tracepoints;
+
+/* The first tracepoint to exceed its pass count.  */
+
+IP_AGENT_EXPORT_VAR struct tracepoint *stopping_tracepoint;
+
+/* True if the trace buffer is full or otherwise no longer usable.  */
+
+IP_AGENT_EXPORT_VAR int trace_buffer_is_full;
+
+/* The first error that occurred during expression evaluation.  */
+
+/* Stored as an int to avoid the IPA ABI being dependent on whatever
+   the compiler decides to use for the enum's underlying type.  Holds
+   enum eval_result_type values.  */
+IP_AGENT_EXPORT_VAR int expr_eval_result = expr_eval_no_error;
+
+EXTERN_C_POP
+
+#ifndef IN_PROCESS_AGENT
+
+/* Pointer to the last tracepoint in the list, new tracepoints are
+   linked in at the end.  */
+
+static struct tracepoint *last_tracepoint;
+
+static const char *eval_result_names[] =
+  {
+    "terror:in the attic",  /* this should never be reported */
+    "terror:empty expression",
+    "terror:empty stack",
+    "terror:stack overflow",
+    "terror:stack underflow",
+    "terror:unhandled opcode",
+    "terror:unrecognized opcode",
+    "terror:divide by zero"
+  };
+
+#endif
+
+/* The tracepoint in which the error occurred.  */
+
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR struct tracepoint *error_tracepoint;
+EXTERN_C_POP
+
+struct trace_state_variable
+{
+  /* This is the name of the variable as used in GDB.  The target
+     doesn't use the name, but needs to have it for saving and
+     reconnection purposes.  */
+  char *name;
+
+  /* This number identifies the variable uniquely.  Numbers may be
+     assigned either by the target (in the case of builtin variables),
+     or by GDB, and are presumed unique during the course of a trace
+     experiment.  */
+  int number;
+
+  /* The variable's initial value, a 64-bit signed integer always.  */
+  LONGEST initial_value;
+
+  /* The variable's value, a 64-bit signed integer always.  */
+  LONGEST value;
+
+  /* Pointer to a getter function, used to supply computed values.  */
+  LONGEST (*getter) (void);
+
+  /* Link to the next variable.  */
+  struct trace_state_variable *next;
+};
+
+/* Linked list of all trace state variables.  */
+
+#ifdef IN_PROCESS_AGENT
+struct trace_state_variable *alloced_trace_state_variables;
+#endif
+
+IP_AGENT_EXPORT_VAR struct trace_state_variable *trace_state_variables;
+
+/* The results of tracing go into a fixed-size space known as the
+   "trace buffer".  Because usage follows a limited number of
+   patterns, we manage it ourselves rather than with malloc.  Basic
+   rules are that we create only one trace frame at a time, each is
+   variable in size, they are never moved once created, and we only
+   discard if we are doing a circular buffer, and then only the oldest
+   ones.  Each trace frame includes its own size, so we don't need to
+   link them together, and the trace frame number is relative to the
+   first one, so we don't need to record numbers.  A trace frame also
+   records the number of the tracepoint that created it.  The data
+   itself is a series of blocks, each introduced by a single character
+   and with a defined format.  Each type of block has enough
+   type/length info to allow scanners to jump quickly from one block
+   to the next without reading each byte in the block.  */
+
+/* Trace buffer management would be simple - advance a free pointer
+   from beginning to end, then stop - were it not for the circular
+   buffer option, which is a useful way to prevent a trace run from
+   stopping prematurely because the buffer filled up.  In the circular
+   case, the location of the first trace frame (trace_buffer_start)
+   moves as old trace frames are discarded.  Also, since we grow trace
+   frames incrementally as actions are performed, we wrap around to
+   the beginning of the trace buffer.  This is per-block, so each
+   block within a trace frame remains contiguous.  Things get messy
+   when the wrapped-around trace frame is the one being discarded; the
+   free space ends up in two parts at opposite ends of the buffer.  */
+
+#ifndef ATTR_PACKED
+#  if defined(__GNUC__)
+#    define ATTR_PACKED __attribute__ ((packed))
+#  else
+#    define ATTR_PACKED /* nothing */
+#  endif
+#endif
+
+/* The data collected at a tracepoint hit.  This object should be as
+   small as possible, since there may be a great many of them.  We do
+   not need to keep a frame number, because they are all sequential
+   and there are no deletions; so the Nth frame in the buffer is
+   always frame number N.  */
+
+struct traceframe
+{
+  /* Number of the tracepoint that collected this traceframe.  A value
+     of 0 indicates the current end of the trace buffer.  We make this
+     a 16-bit field because it's never going to happen that GDB's
+     numbering of tracepoints reaches 32,000.  */
+  int tpnum : 16;
+
+  /* The size of the data in this trace frame.  We limit this to 32
+     bits, even on a 64-bit target, because it's just implausible that
+     one is validly going to collect 4 gigabytes of data at a single
+     tracepoint hit.  */
+  unsigned int data_size : 32;
+
+  /* The base of the trace data, which is contiguous from this point.  */
+  unsigned char data[0];
+
+} ATTR_PACKED;
+
+/* The size of the EOB marker, in bytes.  A traceframe with zeroed
+   fields (and no data) marks the end of trace data.  */
+#define TRACEFRAME_EOB_MARKER_SIZE offsetof (struct traceframe, data)
+
+/* This flag is true if the trace buffer is circular, meaning that
+   when it fills, the oldest trace frames are discarded in order to
+   make room.  */
+
+#ifndef IN_PROCESS_AGENT
+static int circular_trace_buffer;
+#endif
+
+/* Size of the trace buffer.  */
+
+static LONGEST trace_buffer_size;
+
+EXTERN_C_PUSH
+
+/* Pointer to the block of memory that traceframes all go into.  */
+
+IP_AGENT_EXPORT_VAR unsigned char *trace_buffer_lo;
+
+/* Pointer to the end of the trace buffer, more precisely to the byte
+   after the end of the buffer.  */
+
+IP_AGENT_EXPORT_VAR unsigned char *trace_buffer_hi;
+
+EXTERN_C_POP
+
+/* Control structure holding the read/write/etc. pointers into the
+   trace buffer.  We need more than one of these to implement a
+   transaction-like mechanism to guarantees that both GDBserver and the
+   in-process agent can try to change the trace buffer
+   simultaneously.  */
+
+struct trace_buffer_control
+{
+  /* Pointer to the first trace frame in the buffer.  In the
+     non-circular case, this is equal to trace_buffer_lo, otherwise it
+     moves around in the buffer.  */
+  unsigned char *start;
+
+  /* Pointer to the free part of the trace buffer.  Note that we clear
+     several bytes at and after this pointer, so that traceframe
+     scans/searches terminate properly.  */
+  unsigned char *free;
+
+  /* Pointer to the byte after the end of the free part.  Note that
+     this may be smaller than trace_buffer_free in the circular case,
+     and means that the free part is in two pieces.  Initially it is
+     equal to trace_buffer_hi, then is generally equivalent to
+     trace_buffer_start.  */
+  unsigned char *end_free;
+
+  /* Pointer to the wraparound.  If not equal to trace_buffer_hi, then
+     this is the point at which the trace data breaks, and resumes at
+     trace_buffer_lo.  */
+  unsigned char *wrap;
+};
+
+/* Same as above, to be used by GDBserver when updating the in-process
+   agent.  */
+struct ipa_trace_buffer_control
+{
+  uintptr_t start;
+  uintptr_t free;
+  uintptr_t end_free;
+  uintptr_t wrap;
+};
+
+
+/* We have possibly both GDBserver and an inferior thread accessing
+   the same IPA trace buffer memory.  The IPA is the producer (tries
+   to put new frames in the buffer), while GDBserver occasionally
+   consumes them, that is, flushes the IPA's buffer into its own
+   buffer.  Both sides need to update the trace buffer control
+   pointers (current head, tail, etc.).  We can't use a global lock to
+   synchronize the accesses, as otherwise we could deadlock GDBserver
+   (if the thread holding the lock stops for a signal, say).  So
+   instead of that, we use a transaction scheme where GDBserver writes
+   always prevail over the IPAs writes, and, we have the IPA detect
+   the commit failure/overwrite, and retry the whole attempt.  This is
+   mainly implemented by having a global token object that represents
+   who wrote last to the buffer control structure.  We need to freeze
+   any inferior writing to the buffer while GDBserver touches memory,
+   so that the inferior can correctly detect that GDBserver had been
+   there, otherwise, it could mistakingly think its commit was
+   successful; that's implemented by simply having GDBserver set a
+   breakpoint the inferior hits if it is the critical region.
+
+   There are three cycling trace buffer control structure copies
+   (buffer head, tail, etc.), with the token object including an index
+   indicating which is current live copy.  The IPA tentatively builds
+   an updated copy in a non-current control structure, while GDBserver
+   always clobbers the current version directly.  The IPA then tries
+   to atomically "commit" its version; if GDBserver clobbered the
+   structure meanwhile, that will fail, and the IPA restarts the
+   allocation process.
+
+   Listing the step in further detail, we have:
+
+  In-process agent (producer):
+
+  - passes by `about_to_request_buffer_space' breakpoint/lock
+
+  - reads current token, extracts current trace buffer control index,
+    and starts tentatively updating the rightmost one (0->1, 1->2,
+    2->0).  Note that only one inferior thread is executing this code
+    at any given time, due to an outer lock in the jump pads.
+
+  - updates counters, and tries to commit the token.
+
+  - passes by second `about_to_request_buffer_space' breakpoint/lock,
+    leaving the sync region.
+
+  - checks if the update was effective.
+
+  - if trace buffer was found full, hits flush_trace_buffer
+    breakpoint, and restarts later afterwards.
+
+  GDBserver (consumer):
+
+  - sets `about_to_request_buffer_space' breakpoint/lock.
+
+  - updates the token unconditionally, using the current buffer
+    control index, since it knows that the IP agent always writes to
+    the rightmost, and due to the breakpoint, at most one IP thread
+    can try to update the trace buffer concurrently to GDBserver, so
+    there will be no danger of trace buffer control index wrap making
+    the IPA write to the same index as GDBserver.
+
+  - flushes the IP agent's trace buffer completely, and updates the
+    current trace buffer control structure.  GDBserver *always* wins.
+
+  - removes the `about_to_request_buffer_space' breakpoint.
+
+The token is stored in the `trace_buffer_ctrl_curr' variable.
+Internally, it's bits are defined as:
+
+ |-------------+-----+-------------+--------+-------------+--------------|
+ | Bit offsets |  31 |   30 - 20   |   19   |    18-8     |     7-0      |
+ |-------------+-----+-------------+--------+-------------+--------------|
+ | What        | GSB | PC (11-bit) | unused | CC (11-bit) | TBCI (8-bit) |
+ |-------------+-----+-------------+--------+-------------+--------------|
+
+ GSB  - GDBserver Stamp Bit
+ PC   - Previous Counter
+ CC   - Current Counter
+ TBCI - Trace Buffer Control Index
+
+
+An IPA update of `trace_buffer_ctrl_curr' does:
+
+    - read CC from the current token, save as PC.
+    - updates pointers
+    - atomically tries to write PC+1,CC
+
+A GDBserver update of `trace_buffer_ctrl_curr' does:
+
+    - reads PC and CC from the current token.
+    - updates pointers
+    - writes GSB,PC,CC
+*/
+
+/* These are the bits of `trace_buffer_ctrl_curr' that are reserved
+   for the counters described below.  The cleared bits are used to
+   hold the index of the items of the `trace_buffer_ctrl' array that
+   is "current".  */
+#define GDBSERVER_FLUSH_COUNT_MASK        0xfffffff0
+
+/* `trace_buffer_ctrl_curr' contains two counters.  The `previous'
+   counter, and the `current' counter.  */
+
+#define GDBSERVER_FLUSH_COUNT_MASK_PREV   0x7ff00000
+#define GDBSERVER_FLUSH_COUNT_MASK_CURR   0x0007ff00
+
+/* When GDBserver update the IP agent's `trace_buffer_ctrl_curr', it
+   always stamps this bit as set.  */
+#define GDBSERVER_UPDATED_FLUSH_COUNT_BIT 0x80000000
+
+#ifdef IN_PROCESS_AGENT
+IP_AGENT_EXPORT_VAR struct trace_buffer_control trace_buffer_ctrl[3];
+IP_AGENT_EXPORT_VAR unsigned int trace_buffer_ctrl_curr;
+
+# define TRACE_BUFFER_CTRL_CURR \
+  (trace_buffer_ctrl_curr & ~GDBSERVER_FLUSH_COUNT_MASK)
+
+#else
+
+/* The GDBserver side agent only needs one instance of this object, as
+   it doesn't need to sync with itself.  Define it as array anyway so
+   that the rest of the code base doesn't need to care for the
+   difference.  */
+struct trace_buffer_control trace_buffer_ctrl[1];
+# define TRACE_BUFFER_CTRL_CURR 0
+#endif
+
+/* These are convenience macros used to access the current trace
+   buffer control in effect.  */
+#define trace_buffer_start (trace_buffer_ctrl[TRACE_BUFFER_CTRL_CURR].start)
+#define trace_buffer_free (trace_buffer_ctrl[TRACE_BUFFER_CTRL_CURR].free)
+#define trace_buffer_end_free \
+  (trace_buffer_ctrl[TRACE_BUFFER_CTRL_CURR].end_free)
+#define trace_buffer_wrap (trace_buffer_ctrl[TRACE_BUFFER_CTRL_CURR].wrap)
+
+
+/* Macro that returns a pointer to the first traceframe in the buffer.  */
+
+#define FIRST_TRACEFRAME() ((struct traceframe *) trace_buffer_start)
+
+/* Macro that returns a pointer to the next traceframe in the buffer.
+   If the computed location is beyond the wraparound point, subtract
+   the offset of the wraparound.  */
+
+#define NEXT_TRACEFRAME_1(TF) \
+  (((unsigned char *) (TF)) + sizeof (struct traceframe) + (TF)->data_size)
+
+#define NEXT_TRACEFRAME(TF) \
+  ((struct traceframe *) (NEXT_TRACEFRAME_1 (TF)  \
+			  - ((NEXT_TRACEFRAME_1 (TF) >= trace_buffer_wrap) \
+			     ? (trace_buffer_wrap - trace_buffer_lo)	\
+			     : 0)))
+
+/* The difference between these counters represents the total number
+   of complete traceframes present in the trace buffer.  The IP agent
+   writes to the write count, GDBserver writes to read count.  */
+
+IP_AGENT_EXPORT_VAR unsigned int traceframe_write_count;
+IP_AGENT_EXPORT_VAR unsigned int traceframe_read_count;
+
+/* Convenience macro.  */
+
+#define traceframe_count \
+  ((unsigned int) (traceframe_write_count - traceframe_read_count))
+
+/* The count of all traceframes created in the current run, including
+   ones that were discarded to make room.  */
+
+IP_AGENT_EXPORT_VAR int traceframes_created;
+
+#ifndef IN_PROCESS_AGENT
+
+/* Read-only regions are address ranges whose contents don't change,
+   and so can be read from target memory even while looking at a trace
+   frame.  Without these, disassembly for instance will likely fail,
+   because the program code is not usually collected into a trace
+   frame.  This data structure does not need to be very complicated or
+   particularly efficient, it's only going to be used occasionally,
+   and only by some commands.  */
+
+struct readonly_region
+{
+  /* The bounds of the region.  */
+  CORE_ADDR start, end;
+
+  /* Link to the next one.  */
+  struct readonly_region *next;
+};
+
+/* Linked list of readonly regions.  This list stays in effect from
+   one tstart to the next.  */
+
+static struct readonly_region *readonly_regions;
+
+#endif
+
+/* The global that controls tracing overall.  */
+
+IP_AGENT_EXPORT_VAR int tracing;
+
+#ifndef IN_PROCESS_AGENT
+
+/* Controls whether tracing should continue after GDB disconnects.  */
+
+int disconnected_tracing;
+
+/* The reason for the last tracing run to have stopped.  We initialize
+   to a distinct string so that GDB can distinguish between "stopped
+   after running" and "stopped because never run" cases.  */
+
+static const char *tracing_stop_reason = "tnotrun";
+
+static int tracing_stop_tpnum;
+
+/* 64-bit timestamps for the trace run's start and finish, expressed
+   in microseconds from the Unix epoch.  */
+
+LONGEST tracing_start_time;
+LONGEST tracing_stop_time;
+
+/* The (optional) user-supplied name of the user that started the run.
+   This is an arbitrary string, and may be NULL.  */
+
+char *tracing_user_name;
+
+/* Optional user-supplied text describing the run.  This is
+   an arbitrary string, and may be NULL.  */
+
+char *tracing_notes;
+
+/* Optional user-supplied text explaining a tstop command.  This is an
+   arbitrary string, and may be NULL.  */
+
+char *tracing_stop_note;
+
+#endif
+
+/* Functions local to this file.  */
+
+/* Base "class" for tracepoint type specific data to be passed down to
+   collect_data_at_tracepoint.  */
+struct tracepoint_hit_ctx
+{
+  enum tracepoint_type type;
+};
+
+#ifdef IN_PROCESS_AGENT
+
+/* Fast/jump tracepoint specific data to be passed down to
+   collect_data_at_tracepoint.  */
+struct fast_tracepoint_ctx
+{
+  struct tracepoint_hit_ctx base;
+
+  struct regcache regcache;
+  int regcache_initted;
+  unsigned char *regspace;
+
+  unsigned char *regs;
+  struct tracepoint *tpoint;
+};
+
+/* Static tracepoint specific data to be passed down to
+   collect_data_at_tracepoint.  */
+struct static_tracepoint_ctx
+{
+  struct tracepoint_hit_ctx base;
+
+  /* The regcache corresponding to the registers state at the time of
+     the tracepoint hit.  Initialized lazily, from REGS.  */
+  struct regcache regcache;
+  int regcache_initted;
+
+  /* The buffer space REGCACHE above uses.  We use a separate buffer
+     instead of letting the regcache malloc for both signal safety and
+     performance reasons; this is allocated on the stack instead.  */
+  unsigned char *regspace;
+
+  /* The register buffer as passed on by lttng/ust.  */
+  struct registers *regs;
+
+  /* The "printf" formatter and the args the user passed to the marker
+     call.  We use this to be able to collect "static trace data"
+     ($_sdata).  */
+  const char *fmt;
+  va_list *args;
+
+  /* The GDB tracepoint matching the probed marker that was "hit".  */
+  struct tracepoint *tpoint;
+};
+
+#else
+
+/* Static tracepoint specific data to be passed down to
+   collect_data_at_tracepoint.  */
+struct trap_tracepoint_ctx
+{
+  struct tracepoint_hit_ctx base;
+
+  struct regcache *regcache;
+};
+
+#endif
+
+#ifndef IN_PROCESS_AGENT
+static CORE_ADDR traceframe_get_pc (struct traceframe *tframe);
+static int traceframe_read_tsv (int num, LONGEST *val);
+#endif
+
+static int condition_true_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+					 struct tracepoint *tpoint);
+
+#ifndef IN_PROCESS_AGENT
+static void clear_readonly_regions (void);
+static void clear_installed_tracepoints (void);
+#endif
+
+static void collect_data_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+					CORE_ADDR stop_pc,
+					struct tracepoint *tpoint);
+#ifndef IN_PROCESS_AGENT
+static void collect_data_at_step (struct tracepoint_hit_ctx *ctx,
+				  CORE_ADDR stop_pc,
+				  struct tracepoint *tpoint, int current_step);
+static void compile_tracepoint_condition (struct tracepoint *tpoint,
+					  CORE_ADDR *jump_entry);
+#endif
+static void do_action_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+				     CORE_ADDR stop_pc,
+				     struct tracepoint *tpoint,
+				     struct traceframe *tframe,
+				     struct tracepoint_action *taction);
+
+#ifndef IN_PROCESS_AGENT
+static struct tracepoint *fast_tracepoint_from_ipa_tpoint_address (CORE_ADDR);
+
+static void install_tracepoint (struct tracepoint *, char *own_buf);
+static void download_tracepoint (struct tracepoint *);
+static int install_fast_tracepoint (struct tracepoint *, char *errbuf);
+static void clone_fast_tracepoint (struct tracepoint *to,
+				   const struct tracepoint *from);
+#endif
+
+static LONGEST get_timestamp (void);
+
+#if defined(__GNUC__)
+#  define memory_barrier() asm volatile ("" : : : "memory")
+#else
+#  define memory_barrier() do {} while (0)
+#endif
+
+/* We only build the IPA if this builtin is supported, and there are
+   no uses of this in GDBserver itself, so we're safe in defining this
+   unconditionally.  */
+#define cmpxchg(mem, oldval, newval) \
+  __sync_val_compare_and_swap (mem, oldval, newval)
+
+/* Record that an error occurred during expression evaluation.  */
+
+static void
+record_tracepoint_error (struct tracepoint *tpoint, const char *which,
+			 enum eval_result_type rtype)
+{
+  trace_debug ("Tracepoint %d at %s %s eval reports error %d",
+	       tpoint->number, paddress (tpoint->address), which, rtype);
+
+#ifdef IN_PROCESS_AGENT
+  /* Only record the first error we get.  */
+  if (cmpxchg (&expr_eval_result,
+	       expr_eval_no_error,
+	       rtype) != expr_eval_no_error)
+    return;
+#else
+  if (expr_eval_result != expr_eval_no_error)
+    return;
+#endif
+
+  error_tracepoint = tpoint;
+}
+
+/* Trace buffer management.  */
+
+static void
+clear_trace_buffer (void)
+{
+  trace_buffer_start = trace_buffer_lo;
+  trace_buffer_free = trace_buffer_lo;
+  trace_buffer_end_free = trace_buffer_hi;
+  trace_buffer_wrap = trace_buffer_hi;
+  /* A traceframe with zeroed fields marks the end of trace data.  */
+  ((struct traceframe *) trace_buffer_free)->tpnum = 0;
+  ((struct traceframe *) trace_buffer_free)->data_size = 0;
+  traceframe_read_count = traceframe_write_count = 0;
+  traceframes_created = 0;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+static void
+clear_inferior_trace_buffer (void)
+{
+  CORE_ADDR ipa_trace_buffer_lo;
+  CORE_ADDR ipa_trace_buffer_hi;
+  struct traceframe ipa_traceframe = { 0 };
+  struct ipa_trace_buffer_control ipa_trace_buffer_ctrl;
+
+  read_inferior_data_pointer (ipa_sym_addrs.addr_trace_buffer_lo,
+			      &ipa_trace_buffer_lo);
+  read_inferior_data_pointer (ipa_sym_addrs.addr_trace_buffer_hi,
+			      &ipa_trace_buffer_hi);
+
+  ipa_trace_buffer_ctrl.start = ipa_trace_buffer_lo;
+  ipa_trace_buffer_ctrl.free = ipa_trace_buffer_lo;
+  ipa_trace_buffer_ctrl.end_free = ipa_trace_buffer_hi;
+  ipa_trace_buffer_ctrl.wrap = ipa_trace_buffer_hi;
+
+  /* A traceframe with zeroed fields marks the end of trace data.  */
+  target_write_memory (ipa_sym_addrs.addr_trace_buffer_ctrl,
+			 (unsigned char *) &ipa_trace_buffer_ctrl,
+			 sizeof (ipa_trace_buffer_ctrl));
+
+  write_inferior_uinteger (ipa_sym_addrs.addr_trace_buffer_ctrl_curr, 0);
+
+  /* A traceframe with zeroed fields marks the end of trace data.  */
+  target_write_memory (ipa_trace_buffer_lo,
+			 (unsigned char *) &ipa_traceframe,
+			 sizeof (ipa_traceframe));
+
+  write_inferior_uinteger (ipa_sym_addrs.addr_traceframe_write_count, 0);
+  write_inferior_uinteger (ipa_sym_addrs.addr_traceframe_read_count, 0);
+  write_inferior_integer (ipa_sym_addrs.addr_traceframes_created, 0);
+}
+
+#endif
+
+static void
+init_trace_buffer (LONGEST bufsize)
+{
+  size_t alloc_size;
+
+  trace_buffer_size = bufsize;
+
+  /* Make sure to internally allocate at least space for the EOB
+     marker.  */
+  alloc_size = (bufsize < TRACEFRAME_EOB_MARKER_SIZE
+		? TRACEFRAME_EOB_MARKER_SIZE : bufsize);
+  trace_buffer_lo = (unsigned char *) xrealloc (trace_buffer_lo, alloc_size);
+
+  trace_buffer_hi = trace_buffer_lo + trace_buffer_size;
+
+  clear_trace_buffer ();
+}
+
+#ifdef IN_PROCESS_AGENT
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC void about_to_request_buffer_space (void);
+
+IP_AGENT_EXPORT_FUNC void
+about_to_request_buffer_space (void)
+{
+  /* GDBserver places breakpoint here while it goes about to flush
+     data at random times.  */
+  UNKNOWN_SIDE_EFFECTS();
+}
+
+#endif
+
+/* Carve out a piece of the trace buffer, returning NULL in case of
+   failure.  */
+
+static void *
+trace_buffer_alloc (size_t amt)
+{
+  unsigned char *rslt;
+  struct trace_buffer_control *tbctrl;
+  unsigned int curr;
+#ifdef IN_PROCESS_AGENT
+  unsigned int prev, prev_filtered;
+  unsigned int commit_count;
+  unsigned int commit;
+  unsigned int readout;
+#else
+  struct traceframe *oldest;
+  unsigned char *new_start;
+#endif
+
+  trace_debug ("Want to allocate %ld+%ld bytes in trace buffer",
+	       (long) amt, (long) sizeof (struct traceframe));
+
+  /* Account for the EOB marker.  */
+  amt += TRACEFRAME_EOB_MARKER_SIZE;
+
+#ifdef IN_PROCESS_AGENT
+ again:
+  memory_barrier ();
+
+  /* Read the current token and extract the index to try to write to,
+     storing it in CURR.  */
+  prev = trace_buffer_ctrl_curr;
+  prev_filtered = prev & ~GDBSERVER_FLUSH_COUNT_MASK;
+  curr = prev_filtered + 1;
+  if (curr > 2)
+    curr = 0;
+
+  about_to_request_buffer_space ();
+
+  /* Start out with a copy of the current state.  GDBserver may be
+     midway writing to the PREV_FILTERED TBC, but, that's OK, we won't
+     be able to commit anyway if that happens.  */
+  trace_buffer_ctrl[curr]
+    = trace_buffer_ctrl[prev_filtered];
+  trace_debug ("trying curr=%u", curr);
+#else
+  /* The GDBserver's agent doesn't need all that syncing, and always
+     updates TCB 0 (there's only one, mind you).  */
+  curr = 0;
+#endif
+  tbctrl = &trace_buffer_ctrl[curr];
+
+  /* Offsets are easier to grok for debugging than raw addresses,
+     especially for the small trace buffer sizes that are useful for
+     testing.  */
+  trace_debug ("Trace buffer [%d] start=%d free=%d endfree=%d wrap=%d hi=%d",
+	       curr,
+	       (int) (tbctrl->start - trace_buffer_lo),
+	       (int) (tbctrl->free - trace_buffer_lo),
+	       (int) (tbctrl->end_free - trace_buffer_lo),
+	       (int) (tbctrl->wrap - trace_buffer_lo),
+	       (int) (trace_buffer_hi - trace_buffer_lo));
+
+  /* The algorithm here is to keep trying to get a contiguous block of
+     the requested size, possibly discarding older traceframes to free
+     up space.  Since free space might come in one or two pieces,
+     depending on whether discarded traceframes wrapped around at the
+     high end of the buffer, we test both pieces after each
+     discard.  */
+  while (1)
+    {
+      /* First, if we have two free parts, try the upper one first.  */
+      if (tbctrl->end_free < tbctrl->free)
+	{
+	  if (tbctrl->free + amt <= trace_buffer_hi)
+	    /* We have enough in the upper part.  */
+	    break;
+	  else
+	    {
+	      /* Our high part of free space wasn't enough.  Give up
+		 on it for now, set wraparound.  We will recover the
+		 space later, if/when the wrapped-around traceframe is
+		 discarded.  */
+	      trace_debug ("Upper part too small, setting wraparound");
+	      tbctrl->wrap = tbctrl->free;
+	      tbctrl->free = trace_buffer_lo;
+	    }
+	}
+
+      /* The normal case.  */
+      if (tbctrl->free + amt <= tbctrl->end_free)
+	break;
+
+#ifdef IN_PROCESS_AGENT
+      /* The IP Agent's buffer is always circular.  It isn't used
+	 currently, but `circular_trace_buffer' could represent
+	 GDBserver's mode.  If we didn't find space, ask GDBserver to
+	 flush.  */
+
+      flush_trace_buffer ();
+      memory_barrier ();
+      if (tracing)
+	{
+	  trace_debug ("gdbserver flushed buffer, retrying");
+	  goto again;
+	}
+
+      /* GDBserver cancelled the tracing.  Bail out as well.  */
+      return NULL;
+#else
+      /* If we're here, then neither part is big enough, and
+	 non-circular trace buffers are now full.  */
+      if (!circular_trace_buffer)
+	{
+	  trace_debug ("Not enough space in the trace buffer");
+	  return NULL;
+	}
+
+      trace_debug ("Need more space in the trace buffer");
+
+      /* If we have a circular buffer, we can try discarding the
+	 oldest traceframe and see if that helps.  */
+      oldest = FIRST_TRACEFRAME ();
+      if (oldest->tpnum == 0)
+	{
+	  /* Not good; we have no traceframes to free.  Perhaps we're
+	     asking for a block that is larger than the buffer?  In
+	     any case, give up.  */
+	  trace_debug ("No traceframes to discard");
+	  return NULL;
+	}
+
+      /* We don't run this code in the in-process agent currently.
+	 E.g., we could leave the in-process agent in autonomous
+	 circular mode if we only have fast tracepoints.  If we do
+	 that, then this bit becomes racy with GDBserver, which also
+	 writes to this counter.  */
+      --traceframe_write_count;
+
+      new_start = (unsigned char *) NEXT_TRACEFRAME (oldest);
+      /* If we freed the traceframe that wrapped around, go back
+	 to the non-wrap case.  */
+      if (new_start < tbctrl->start)
+	{
+	  trace_debug ("Discarding past the wraparound");
+	  tbctrl->wrap = trace_buffer_hi;
+	}
+      tbctrl->start = new_start;
+      tbctrl->end_free = tbctrl->start;
+
+      trace_debug ("Discarded a traceframe\n"
+		   "Trace buffer [%d], start=%d free=%d "
+		   "endfree=%d wrap=%d hi=%d",
+		   curr,
+		   (int) (tbctrl->start - trace_buffer_lo),
+		   (int) (tbctrl->free - trace_buffer_lo),
+		   (int) (tbctrl->end_free - trace_buffer_lo),
+		   (int) (tbctrl->wrap - trace_buffer_lo),
+		   (int) (trace_buffer_hi - trace_buffer_lo));
+
+      /* Now go back around the loop.  The discard might have resulted
+	 in either one or two pieces of free space, so we want to try
+	 both before freeing any more traceframes.  */
+#endif
+    }
+
+  /* If we get here, we know we can provide the asked-for space.  */
+
+  rslt = tbctrl->free;
+
+  /* Adjust the request back down, now that we know we have space for
+     the marker, but don't commit to AMT yet, we may still need to
+     restart the operation if GDBserver touches the trace buffer
+     (obviously only important in the in-process agent's version).  */
+  tbctrl->free += (amt - sizeof (struct traceframe));
+
+  /* Or not.  If GDBserver changed the trace buffer behind our back,
+     we get to restart a new allocation attempt.  */
+
+#ifdef IN_PROCESS_AGENT
+  /* Build the tentative token.  */
+  commit_count = (((prev & GDBSERVER_FLUSH_COUNT_MASK_CURR) + 0x100)
+		  & GDBSERVER_FLUSH_COUNT_MASK_CURR);
+  commit = (((prev & GDBSERVER_FLUSH_COUNT_MASK_CURR) << 12)
+	    | commit_count
+	    | curr);
+
+  /* Try to commit it.  */
+  readout = cmpxchg (&trace_buffer_ctrl_curr, prev, commit);
+  if (readout != prev)
+    {
+      trace_debug ("GDBserver has touched the trace buffer, restarting."
+		   " (prev=%08x, commit=%08x, readout=%08x)",
+		   prev, commit, readout);
+      goto again;
+    }
+
+  /* Hold your horses here.  Even if that change was committed,
+     GDBserver could come in, and clobber it.  We need to hold to be
+     able to tell if GDBserver clobbers before or after we committed
+     the change.  Whenever GDBserver goes about touching the IPA
+     buffer, it sets a breakpoint in this routine, so we have a sync
+     point here.  */
+  about_to_request_buffer_space ();
+
+  /* Check if the change has been effective, even if GDBserver stopped
+     us at the breakpoint.  */
+
+  {
+    unsigned int refetch;
+
+    memory_barrier ();
+
+    refetch = trace_buffer_ctrl_curr;
+
+    if (refetch == commit
+	|| ((refetch & GDBSERVER_FLUSH_COUNT_MASK_PREV) >> 12) == commit_count)
+      {
+	/* effective */
+	trace_debug ("change is effective: (prev=%08x, commit=%08x, "
+		     "readout=%08x, refetch=%08x)",
+		     prev, commit, readout, refetch);
+      }
+    else
+      {
+	trace_debug ("GDBserver has touched the trace buffer, not effective."
+		     " (prev=%08x, commit=%08x, readout=%08x, refetch=%08x)",
+		     prev, commit, readout, refetch);
+	goto again;
+      }
+  }
+#endif
+
+  /* We have a new piece of the trace buffer.  Hurray!  */
+
+  /* Add an EOB marker just past this allocation.  */
+  ((struct traceframe *) tbctrl->free)->tpnum = 0;
+  ((struct traceframe *) tbctrl->free)->data_size = 0;
+
+  /* Adjust the request back down, now that we know we have space for
+     the marker.  */
+  amt -= sizeof (struct traceframe);
+
+  if (debug_threads)
+    {
+      trace_debug ("Allocated %d bytes", (int) amt);
+      trace_debug ("Trace buffer [%d] start=%d free=%d "
+		   "endfree=%d wrap=%d hi=%d",
+		   curr,
+		   (int) (tbctrl->start - trace_buffer_lo),
+		   (int) (tbctrl->free - trace_buffer_lo),
+		   (int) (tbctrl->end_free - trace_buffer_lo),
+		   (int) (tbctrl->wrap - trace_buffer_lo),
+		   (int) (trace_buffer_hi - trace_buffer_lo));
+    }
+
+  return rslt;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* Return the total free space.  This is not necessarily the largest
+   block we can allocate, because of the two-part case.  */
+
+static int
+free_space (void)
+{
+  if (trace_buffer_free <= trace_buffer_end_free)
+    return trace_buffer_end_free - trace_buffer_free;
+  else
+    return ((trace_buffer_end_free - trace_buffer_lo)
+	    + (trace_buffer_hi - trace_buffer_free));
+}
+
+/* An 'S' in continuation packets indicates remainder are for
+   while-stepping.  */
+
+static int seen_step_action_flag;
+
+/* Create a tracepoint (location) with given number and address.  Add this
+   new tracepoint to list and sort this list.  */
+
+static struct tracepoint *
+add_tracepoint (int num, CORE_ADDR addr)
+{
+  struct tracepoint *tpoint, **tp_next;
+
+  tpoint = XNEW (struct tracepoint);
+  tpoint->number = num;
+  tpoint->address = addr;
+  tpoint->numactions = 0;
+  tpoint->actions = NULL;
+  tpoint->actions_str = NULL;
+  tpoint->cond = NULL;
+  tpoint->num_step_actions = 0;
+  tpoint->step_actions = NULL;
+  tpoint->step_actions_str = NULL;
+  /* Start all off as regular (slow) tracepoints.  */
+  tpoint->type = trap_tracepoint;
+  tpoint->orig_size = -1;
+  tpoint->source_strings = NULL;
+  tpoint->compiled_cond = 0;
+  tpoint->handle = NULL;
+  tpoint->next = NULL;
+
+  /* Find a place to insert this tracepoint into list in order to keep
+     the tracepoint list still in the ascending order.  There may be
+     multiple tracepoints at the same address as TPOINT's, and this
+     guarantees TPOINT is inserted after all the tracepoints which are
+     set at the same address.  For example, fast tracepoints A, B, C are
+     set at the same address, and D is to be insert at the same place as
+     well,
+
+     -->| A |--> | B |-->| C |->...
+
+     One jump pad was created for tracepoint A, B, and C, and the target
+     address of A is referenced/used in jump pad.  So jump pad will let
+     inferior jump to A.  If D is inserted in front of A, like this,
+
+     -->| D |-->| A |--> | B |-->| C |->...
+
+     without updating jump pad, D is not reachable during collect, which
+     is wrong.  As we can see, the order of B, C and D doesn't matter, but
+     A should always be the `first' one.  */
+  for (tp_next = &tracepoints;
+       (*tp_next) != NULL && (*tp_next)->address <= tpoint->address;
+       tp_next = &(*tp_next)->next)
+    ;
+  tpoint->next = *tp_next;
+  *tp_next = tpoint;
+  last_tracepoint = tpoint;
+
+  seen_step_action_flag = 0;
+
+  return tpoint;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* Return the tracepoint with the given number and address, or NULL.  */
+
+static struct tracepoint *
+find_tracepoint (int id, CORE_ADDR addr)
+{
+  struct tracepoint *tpoint;
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    if (tpoint->number == id && tpoint->address == addr)
+      return tpoint;
+
+  return NULL;
+}
+
+/* Remove TPOINT from global list.  */
+
+static void
+remove_tracepoint (struct tracepoint *tpoint)
+{
+  struct tracepoint *tp, *tp_prev;
+
+  for (tp = tracepoints, tp_prev = NULL; tp && tp != tpoint;
+       tp_prev = tp, tp = tp->next)
+    ;
+
+  if (tp)
+    {
+      if (tp_prev)
+	tp_prev->next = tp->next;
+      else
+	tracepoints = tp->next;
+
+      xfree (tp);
+    }
+}
+
+/* There may be several tracepoints with the same number (because they
+   are "locations", in GDB parlance); return the next one after the
+   given tracepoint, or search from the beginning of the list if the
+   first argument is NULL.  */
+
+static struct tracepoint *
+find_next_tracepoint_by_number (struct tracepoint *prev_tp, int num)
+{
+  struct tracepoint *tpoint;
+
+  if (prev_tp)
+    tpoint = prev_tp->next;
+  else
+    tpoint = tracepoints;
+  for (; tpoint; tpoint = tpoint->next)
+    if (tpoint->number == num)
+      return tpoint;
+
+  return NULL;
+}
+
+#endif
+
+/* Append another action to perform when the tracepoint triggers.  */
+
+static void
+add_tracepoint_action (struct tracepoint *tpoint, const char *packet)
+{
+  const char *act;
+
+  if (*packet == 'S')
+    {
+      seen_step_action_flag = 1;
+      ++packet;
+    }
+
+  act = packet;
+
+  while (*act)
+    {
+      const char *act_start = act;
+      struct tracepoint_action *action = NULL;
+
+      switch (*act)
+	{
+	case 'M':
+	  {
+	    struct collect_memory_action *maction =
+	      XNEW (struct collect_memory_action);
+	    ULONGEST basereg;
+	    int is_neg;
+
+	    maction->base.type = *act;
+	    action = &maction->base;
+
+	    ++act;
+	    is_neg = (*act == '-');
+	    if (*act == '-')
+	      ++act;
+	    act = unpack_varlen_hex (act, &basereg);
+	    ++act;
+	    act = unpack_varlen_hex (act, &maction->addr);
+	    ++act;
+	    act = unpack_varlen_hex (act, &maction->len);
+	    maction->basereg = (is_neg
+				? - (int) basereg
+				: (int) basereg);
+	    trace_debug ("Want to collect %s bytes at 0x%s (basereg %d)",
+			 pulongest (maction->len),
+			 paddress (maction->addr), maction->basereg);
+	    break;
+	  }
+	case 'R':
+	  {
+	    struct collect_registers_action *raction =
+	      XNEW (struct collect_registers_action);
+
+	    raction->base.type = *act;
+	    action = &raction->base;
+
+	    trace_debug ("Want to collect registers");
+	    ++act;
+	    /* skip past hex digits of mask for now */
+	    while (isxdigit(*act))
+	      ++act;
+	    break;
+	  }
+	case 'L':
+	  {
+	    struct collect_static_trace_data_action *raction =
+	      XNEW (struct collect_static_trace_data_action);
+
+	    raction->base.type = *act;
+	    action = &raction->base;
+
+	    trace_debug ("Want to collect static trace data");
+	    ++act;
+	    break;
+	  }
+	case 'S':
+	  trace_debug ("Unexpected step action, ignoring");
+	  ++act;
+	  break;
+	case 'X':
+	  {
+	    struct eval_expr_action *xaction = XNEW (struct eval_expr_action);
+
+	    xaction->base.type = *act;
+	    action = &xaction->base;
+
+	    trace_debug ("Want to evaluate expression");
+	    xaction->expr = gdb_parse_agent_expr (&act);
+	    break;
+	  }
+	default:
+	  trace_debug ("unknown trace action '%c', ignoring...", *act);
+	  break;
+	case '-':
+	  break;
+	}
+
+      if (action == NULL)
+	break;
+
+      if (seen_step_action_flag)
+	{
+	  tpoint->num_step_actions++;
+
+	  tpoint->step_actions
+	    = XRESIZEVEC (struct tracepoint_action *, tpoint->step_actions,
+			  tpoint->num_step_actions);
+	  tpoint->step_actions_str
+	    = XRESIZEVEC (char *, tpoint->step_actions_str,
+			  tpoint->num_step_actions);
+	  tpoint->step_actions[tpoint->num_step_actions - 1] = action;
+	  tpoint->step_actions_str[tpoint->num_step_actions - 1]
+	    = savestring (act_start, act - act_start);
+	}
+      else
+	{
+	  tpoint->numactions++;
+	  tpoint->actions
+	    = XRESIZEVEC (struct tracepoint_action *, tpoint->actions,
+			  tpoint->numactions);
+	  tpoint->actions_str
+	    = XRESIZEVEC (char *, tpoint->actions_str, tpoint->numactions);
+	  tpoint->actions[tpoint->numactions - 1] = action;
+	  tpoint->actions_str[tpoint->numactions - 1]
+	    = savestring (act_start, act - act_start);
+	}
+    }
+}
+
+#endif
+
+/* Find or create a trace state variable with the given number.  */
+
+static struct trace_state_variable *
+get_trace_state_variable (int num)
+{
+  struct trace_state_variable *tsv;
+
+#ifdef IN_PROCESS_AGENT
+  /* Search for an existing variable.  */
+  for (tsv = alloced_trace_state_variables; tsv; tsv = tsv->next)
+    if (tsv->number == num)
+      return tsv;
+#endif
+
+  /* Search for an existing variable.  */
+  for (tsv = trace_state_variables; tsv; tsv = tsv->next)
+    if (tsv->number == num)
+      return tsv;
+
+  return NULL;
+}
+
+/* Find or create a trace state variable with the given number.  */
+
+static struct trace_state_variable *
+create_trace_state_variable (int num, int gdb)
+{
+  struct trace_state_variable *tsv;
+
+  tsv = get_trace_state_variable (num);
+  if (tsv != NULL)
+    return tsv;
+
+  /* Create a new variable.  */
+  tsv = XNEW (struct trace_state_variable);
+  tsv->number = num;
+  tsv->initial_value = 0;
+  tsv->value = 0;
+  tsv->getter = NULL;
+  tsv->name = NULL;
+#ifdef IN_PROCESS_AGENT
+  if (!gdb)
+    {
+      tsv->next = alloced_trace_state_variables;
+      alloced_trace_state_variables = tsv;
+    }
+  else
+#endif
+    {
+      tsv->next = trace_state_variables;
+      trace_state_variables = tsv;
+    }
+  return tsv;
+}
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC LONGEST get_trace_state_variable_value (int num);
+
+IP_AGENT_EXPORT_FUNC LONGEST
+get_trace_state_variable_value (int num)
+{
+  struct trace_state_variable *tsv;
+
+  tsv = get_trace_state_variable (num);
+
+  if (!tsv)
+    {
+      trace_debug ("No trace state variable %d, skipping value get", num);
+      return 0;
+    }
+
+  /* Call a getter function if we have one.  While it's tempting to
+     set up something to only call the getter once per tracepoint hit,
+     it could run afoul of thread races. Better to let the getter
+     handle it directly, if necessary to worry about it.  */
+  if (tsv->getter)
+    tsv->value = (tsv->getter) ();
+
+  trace_debug ("get_trace_state_variable_value(%d) ==> %s",
+	       num, plongest (tsv->value));
+
+  return tsv->value;
+}
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC void set_trace_state_variable_value (int num,
+							  LONGEST val);
+
+IP_AGENT_EXPORT_FUNC void
+set_trace_state_variable_value (int num, LONGEST val)
+{
+  struct trace_state_variable *tsv;
+
+  tsv = get_trace_state_variable (num);
+
+  if (!tsv)
+    {
+      trace_debug ("No trace state variable %d, skipping value set", num);
+      return;
+    }
+
+  tsv->value = val;
+}
+
+LONGEST
+agent_get_trace_state_variable_value (int num)
+{
+  return get_trace_state_variable_value (num);
+}
+
+void
+agent_set_trace_state_variable_value (int num, LONGEST val)
+{
+  set_trace_state_variable_value (num, val);
+}
+
+static void
+set_trace_state_variable_name (int num, const char *name)
+{
+  struct trace_state_variable *tsv;
+
+  tsv = get_trace_state_variable (num);
+
+  if (!tsv)
+    {
+      trace_debug ("No trace state variable %d, skipping name set", num);
+      return;
+    }
+
+  tsv->name = (char *) name;
+}
+
+static void
+set_trace_state_variable_getter (int num, LONGEST (*getter) (void))
+{
+  struct trace_state_variable *tsv;
+
+  tsv = get_trace_state_variable (num);
+
+  if (!tsv)
+    {
+      trace_debug ("No trace state variable %d, skipping getter set", num);
+      return;
+    }
+
+  tsv->getter = getter;
+}
+
+/* Add a raw traceframe for the given tracepoint.  */
+
+static struct traceframe *
+add_traceframe (struct tracepoint *tpoint)
+{
+  struct traceframe *tframe;
+
+  tframe
+    = (struct traceframe *) trace_buffer_alloc (sizeof (struct traceframe));
+
+  if (tframe == NULL)
+    return NULL;
+
+  tframe->tpnum = tpoint->number;
+  tframe->data_size = 0;
+
+  return tframe;
+}
+
+/* Add a block to the traceframe currently being worked on.  */
+
+static unsigned char *
+add_traceframe_block (struct traceframe *tframe,
+		      struct tracepoint *tpoint, int amt)
+{
+  unsigned char *block;
+
+  if (!tframe)
+    return NULL;
+
+  block = (unsigned char *) trace_buffer_alloc (amt);
+
+  if (!block)
+    return NULL;
+
+  gdb_assert (tframe->tpnum == tpoint->number);
+
+  tframe->data_size += amt;
+  tpoint->traceframe_usage += amt;
+
+  return block;
+}
+
+/* Flag that the current traceframe is finished.  */
+
+static void
+finish_traceframe (struct traceframe *tframe)
+{
+  ++traceframe_write_count;
+  ++traceframes_created;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* Given a traceframe number NUM, find the NUMth traceframe in the
+   buffer.  */
+
+static struct traceframe *
+find_traceframe (int num)
+{
+  struct traceframe *tframe;
+  int tfnum = 0;
+
+  for (tframe = FIRST_TRACEFRAME ();
+       tframe->tpnum != 0;
+       tframe = NEXT_TRACEFRAME (tframe))
+    {
+      if (tfnum == num)
+	return tframe;
+      ++tfnum;
+    }
+
+  return NULL;
+}
+
+static CORE_ADDR
+get_traceframe_address (struct traceframe *tframe)
+{
+  CORE_ADDR addr;
+  struct tracepoint *tpoint;
+
+  addr = traceframe_get_pc (tframe);
+
+  if (addr)
+    return addr;
+
+  /* Fallback strategy, will be incorrect for while-stepping frames
+     and multi-location tracepoints.  */
+  tpoint = find_next_tracepoint_by_number (NULL, tframe->tpnum);
+  return tpoint->address;
+}
+
+/* Search for the next traceframe whose address is inside or outside
+   the given range.  */
+
+static struct traceframe *
+find_next_traceframe_in_range (CORE_ADDR lo, CORE_ADDR hi, int inside_p,
+			       int *tfnump)
+{
+  client_state &cs = get_client_state ();
+  struct traceframe *tframe;
+  CORE_ADDR tfaddr;
+
+  *tfnump = cs.current_traceframe + 1;
+  tframe = find_traceframe (*tfnump);
+  /* The search is not supposed to wrap around.  */
+  if (!tframe)
+    {
+      *tfnump = -1;
+      return NULL;
+    }
+
+  for (; tframe->tpnum != 0; tframe = NEXT_TRACEFRAME (tframe))
+    {
+      tfaddr = get_traceframe_address (tframe);
+      if (inside_p
+	  ? (lo <= tfaddr && tfaddr <= hi)
+	  : (lo > tfaddr || tfaddr > hi))
+	return tframe;
+      ++*tfnump;
+    }
+
+  *tfnump = -1;
+  return NULL;
+}
+
+/* Search for the next traceframe recorded by the given tracepoint.
+   Note that for multi-location tracepoints, this will find whatever
+   location appears first.  */
+
+static struct traceframe *
+find_next_traceframe_by_tracepoint (int num, int *tfnump)
+{
+  client_state &cs = get_client_state ();
+  struct traceframe *tframe;
+
+  *tfnump = cs.current_traceframe + 1;
+  tframe = find_traceframe (*tfnump);
+  /* The search is not supposed to wrap around.  */
+  if (!tframe)
+    {
+      *tfnump = -1;
+      return NULL;
+    }
+
+  for (; tframe->tpnum != 0; tframe = NEXT_TRACEFRAME (tframe))
+    {
+      if (tframe->tpnum == num)
+	return tframe;
+      ++*tfnump;
+    }
+
+  *tfnump = -1;
+  return NULL;
+}
+
+#endif
+
+#ifndef IN_PROCESS_AGENT
+
+/* Clear all past trace state.  */
+
+static void
+cmd_qtinit (char *packet)
+{
+  client_state &cs = get_client_state ();
+  struct trace_state_variable *tsv, *prev, *next;
+
+  /* Can't do this command without a pid attached.  */
+  if (current_thread == NULL)
+    {
+      write_enn (packet);
+      return;
+    }
+
+  /* Make sure we don't try to read from a trace frame.  */
+  cs.current_traceframe = -1;
+
+  stop_tracing ();
+
+  trace_debug ("Initializing the trace");
+
+  clear_installed_tracepoints ();
+  clear_readonly_regions ();
+
+  tracepoints = NULL;
+  last_tracepoint = NULL;
+
+  /* Clear out any leftover trace state variables.  Ones with target
+     defined getters should be kept however.  */
+  prev = NULL;
+  tsv = trace_state_variables;
+  while (tsv)
+    {
+      trace_debug ("Looking at var %d", tsv->number);
+      if (tsv->getter == NULL)
+	{
+	  next = tsv->next;
+	  if (prev)
+	    prev->next = next;
+	  else
+	    trace_state_variables = next;
+	  trace_debug ("Deleting var %d", tsv->number);
+	  free (tsv);
+	  tsv = next;
+	}
+      else
+	{
+	  prev = tsv;
+	  tsv = tsv->next;
+	}
+    }
+
+  clear_trace_buffer ();
+  clear_inferior_trace_buffer ();
+
+  write_ok (packet);
+}
+
+/* Unprobe the UST marker at ADDRESS.  */
+
+static void
+unprobe_marker_at (CORE_ADDR address)
+{
+  char cmd[IPA_CMD_BUF_SIZE];
+
+  sprintf (cmd, "unprobe_marker_at:%s", paddress (address));
+  run_inferior_command (cmd, strlen (cmd) + 1);
+}
+
+/* Restore the program to its pre-tracing state.  This routine may be called
+   in error situations, so it needs to be careful about only restoring
+   from known-valid bits.  */
+
+static void
+clear_installed_tracepoints (void)
+{
+  struct tracepoint *tpoint;
+  struct tracepoint *prev_stpoint;
+
+  pause_all (1);
+
+  prev_stpoint = NULL;
+
+  /* Restore any bytes overwritten by tracepoints.  */
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    {
+      /* Catch the case where we might try to remove a tracepoint that
+	 was never actually installed.  */
+      if (tpoint->handle == NULL)
+	{
+	  trace_debug ("Tracepoint %d at 0x%s was "
+		       "never installed, nothing to clear",
+		       tpoint->number, paddress (tpoint->address));
+	  continue;
+	}
+
+      switch (tpoint->type)
+	{
+	case trap_tracepoint:
+	  {
+	    struct breakpoint *bp
+	      = (struct breakpoint *) tpoint->handle;
+
+	    delete_breakpoint (bp);
+	  }
+	  break;
+	case fast_tracepoint:
+	  {
+	    struct fast_tracepoint_jump *jump
+	      = (struct fast_tracepoint_jump *) tpoint->handle;
+
+	    delete_fast_tracepoint_jump (jump);
+	  }
+	  break;
+	case static_tracepoint:
+	  if (prev_stpoint != NULL
+	      && prev_stpoint->address == tpoint->address)
+	    /* Nothing to do.  We already unprobed a tracepoint set at
+	       this marker address (and there can only be one probe
+	       per marker).  */
+	    ;
+	  else
+	    {
+	      unprobe_marker_at (tpoint->address);
+	      prev_stpoint = tpoint;
+	    }
+	  break;
+	}
+
+      tpoint->handle = NULL;
+    }
+
+  unpause_all (1);
+}
+
+/* Parse a packet that defines a tracepoint.  */
+
+static void
+cmd_qtdp (char *own_buf)
+{
+  int tppacket;
+  /* Whether there is a trailing hyphen at the end of the QTDP packet.  */
+  int trail_hyphen = 0;
+  ULONGEST num;
+  ULONGEST addr;
+  ULONGEST count;
+  struct tracepoint *tpoint;
+  const char *packet = own_buf;
+
+  packet += strlen ("QTDP:");
+
+  /* A hyphen at the beginning marks a packet specifying actions for a
+     tracepoint already supplied.  */
+  tppacket = 1;
+  if (*packet == '-')
+    {
+      tppacket = 0;
+      ++packet;
+    }
+  packet = unpack_varlen_hex (packet, &num);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &addr);
+  ++packet; /* skip a colon */
+
+  /* See if we already have this tracepoint.  */
+  tpoint = find_tracepoint (num, addr);
+
+  if (tppacket)
+    {
+      /* Duplicate tracepoints are never allowed.  */
+      if (tpoint)
+	{
+	  trace_debug ("Tracepoint error: tracepoint %d"
+		       " at 0x%s already exists",
+		       (int) num, paddress (addr));
+	  write_enn (own_buf);
+	  return;
+	}
+
+      tpoint = add_tracepoint (num, addr);
+
+      tpoint->enabled = (*packet == 'E');
+      ++packet; /* skip 'E' */
+      ++packet; /* skip a colon */
+      packet = unpack_varlen_hex (packet, &count);
+      tpoint->step_count = count;
+      ++packet; /* skip a colon */
+      packet = unpack_varlen_hex (packet, &count);
+      tpoint->pass_count = count;
+      /* See if we have any of the additional optional fields.  */
+      while (*packet == ':')
+	{
+	  ++packet;
+	  if (*packet == 'F')
+	    {
+	      tpoint->type = fast_tracepoint;
+	      ++packet;
+	      packet = unpack_varlen_hex (packet, &count);
+	      tpoint->orig_size = count;
+	    }
+	  else if (*packet == 'S')
+	    {
+	      tpoint->type = static_tracepoint;
+	      ++packet;
+	    }
+	  else if (*packet == 'X')
+	    {
+	      tpoint->cond = gdb_parse_agent_expr (&packet);
+	    }
+	  else if (*packet == '-')
+	    break;
+	  else if (*packet == '\0')
+	    break;
+	  else
+	    trace_debug ("Unknown optional tracepoint field");
+	}
+      if (*packet == '-')
+	{
+	  trail_hyphen = 1;
+	  trace_debug ("Also has actions\n");
+	}
+
+      trace_debug ("Defined %stracepoint %d at 0x%s, "
+		   "enabled %d step %" PRIu64 " pass %" PRIu64,
+		   tpoint->type == fast_tracepoint ? "fast "
+		   : tpoint->type == static_tracepoint ? "static " : "",
+		   tpoint->number, paddress (tpoint->address), tpoint->enabled,
+		   tpoint->step_count, tpoint->pass_count);
+    }
+  else if (tpoint)
+    add_tracepoint_action (tpoint, packet);
+  else
+    {
+      trace_debug ("Tracepoint error: tracepoint %d at 0x%s not found",
+		   (int) num, paddress (addr));
+      write_enn (own_buf);
+      return;
+    }
+
+  /* Install tracepoint during tracing only once for each tracepoint location.
+     For each tracepoint loc, GDB may send multiple QTDP packets, and we can
+     determine the last QTDP packet for one tracepoint location by checking
+     trailing hyphen in QTDP packet.  */
+  if (tracing && !trail_hyphen)
+    {
+      struct tracepoint *tp = NULL;
+
+      /* Pause all threads temporarily while we patch tracepoints.  */
+      pause_all (0);
+
+      /* download_tracepoint will update global `tracepoints'
+	 list, so it is unsafe to leave threads in jump pad.  */
+      stabilize_threads ();
+
+      /* Freeze threads.  */
+      pause_all (1);
+
+
+      if (tpoint->type != trap_tracepoint)
+	{
+	  /* Find another fast or static tracepoint at the same address.  */
+	  for (tp = tracepoints; tp; tp = tp->next)
+	    {
+	      if (tp->address == tpoint->address && tp->type == tpoint->type
+		  && tp->number != tpoint->number)
+		break;
+	    }
+
+	  /* TPOINT is installed at the same address as TP.  */
+	  if (tp)
+	    {
+	      if (tpoint->type == fast_tracepoint)
+		clone_fast_tracepoint (tpoint, tp);
+	      else if (tpoint->type == static_tracepoint)
+		tpoint->handle = (void *) -1;
+	    }
+	}
+
+      if (use_agent && tpoint->type == fast_tracepoint
+	  && agent_capability_check (AGENT_CAPA_FAST_TRACE))
+	{
+	  /* Download and install fast tracepoint by agent.  */
+	  if (tracepoint_send_agent (tpoint) == 0)
+	    write_ok (own_buf);
+	  else
+	    {
+	      write_enn (own_buf);
+	      remove_tracepoint (tpoint);
+	    }
+	}
+      else
+	{
+	  download_tracepoint (tpoint);
+
+	  if (tpoint->type == trap_tracepoint || tp == NULL)
+	    {
+	      install_tracepoint (tpoint, own_buf);
+	      if (strcmp (own_buf, "OK") != 0)
+		remove_tracepoint (tpoint);
+	    }
+	  else
+	    write_ok (own_buf);
+	}
+
+      unpause_all (1);
+      return;
+    }
+
+  write_ok (own_buf);
+}
+
+static void
+cmd_qtdpsrc (char *own_buf)
+{
+  ULONGEST num, addr, start, slen;
+  struct tracepoint *tpoint;
+  const char *packet = own_buf;
+  const char *saved;
+  char *srctype, *src;
+  size_t nbytes;
+  struct source_string *last, *newlast;
+
+  packet += strlen ("QTDPsrc:");
+
+  packet = unpack_varlen_hex (packet, &num);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &addr);
+  ++packet; /* skip a colon */
+
+  /* See if we already have this tracepoint.  */
+  tpoint = find_tracepoint (num, addr);
+
+  if (!tpoint)
+    {
+      trace_debug ("Tracepoint error: tracepoint %d at 0x%s not found",
+		   (int) num, paddress (addr));
+      write_enn (own_buf);
+      return;
+    }
+
+  saved = packet;
+  packet = strchr (packet, ':');
+  srctype = (char *) xmalloc (packet - saved + 1);
+  memcpy (srctype, saved, packet - saved);
+  srctype[packet - saved] = '\0';
+  ++packet;
+  packet = unpack_varlen_hex (packet, &start);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &slen);
+  ++packet; /* skip a colon */
+  src = (char *) xmalloc (slen + 1);
+  nbytes = hex2bin (packet, (gdb_byte *) src, strlen (packet) / 2);
+  src[nbytes] = '\0';
+
+  newlast = XNEW (struct source_string);
+  newlast->type = srctype;
+  newlast->str = src;
+  newlast->next = NULL;
+  /* Always add a source string to the end of the list;
+     this keeps sequences of actions/commands in the right
+     order.  */
+  if (tpoint->source_strings)
+    {
+      for (last = tpoint->source_strings; last->next; last = last->next)
+	;
+      last->next = newlast;
+    }
+  else
+    tpoint->source_strings = newlast;
+
+  write_ok (own_buf);
+}
+
+static void
+cmd_qtdv (char *own_buf)
+{
+  ULONGEST num, val, builtin;
+  char *varname;
+  size_t nbytes;
+  struct trace_state_variable *tsv;
+  const char *packet = own_buf;
+
+  packet += strlen ("QTDV:");
+
+  packet = unpack_varlen_hex (packet, &num);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &val);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &builtin);
+  ++packet; /* skip a colon */
+
+  nbytes = strlen (packet) / 2;
+  varname = (char *) xmalloc (nbytes + 1);
+  nbytes = hex2bin (packet, (gdb_byte *) varname, nbytes);
+  varname[nbytes] = '\0';
+
+  tsv = create_trace_state_variable (num, 1);
+  tsv->initial_value = (LONGEST) val;
+  tsv->name = varname;
+
+  set_trace_state_variable_value (num, (LONGEST) val);
+
+  write_ok (own_buf);
+}
+
+static void
+cmd_qtenable_disable (char *own_buf, int enable)
+{
+  const char *packet = own_buf;
+  ULONGEST num, addr;
+  struct tracepoint *tp;
+
+  packet += strlen (enable ? "QTEnable:" : "QTDisable:");
+  packet = unpack_varlen_hex (packet, &num);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &addr);
+
+  tp = find_tracepoint (num, addr);
+
+  if (tp)
+    {
+      if ((enable && tp->enabled) || (!enable && !tp->enabled))
+	{
+	  trace_debug ("Tracepoint %d at 0x%s is already %s",
+		       (int) num, paddress (addr),
+		       enable ? "enabled" : "disabled");
+	  write_ok (own_buf);
+	  return;
+	}
+
+      trace_debug ("%s tracepoint %d at 0x%s",
+		   enable ? "Enabling" : "Disabling",
+		   (int) num, paddress (addr));
+
+      tp->enabled = enable;
+
+      if (tp->type == fast_tracepoint || tp->type == static_tracepoint)
+	{
+	  int ret;
+	  int offset = offsetof (struct tracepoint, enabled);
+	  CORE_ADDR obj_addr = tp->obj_addr_on_target + offset;
+
+	  ret = prepare_to_access_memory ();
+	  if (ret)
+	    {
+	      trace_debug ("Failed to temporarily stop inferior threads");
+	      write_enn (own_buf);
+	      return;
+	    }
+
+	  ret = write_inferior_int8 (obj_addr, enable);
+	  done_accessing_memory ();
+	  
+	  if (ret)
+	    {
+	      trace_debug ("Cannot write enabled flag into "
+			   "inferior process memory");
+	      write_enn (own_buf);
+	      return;
+	    }
+	}
+
+      write_ok (own_buf);
+    }
+  else
+    {
+      trace_debug ("Tracepoint %d at 0x%s not found",
+		   (int) num, paddress (addr));
+      write_enn (own_buf);
+    }
+}
+
+static void
+cmd_qtv (char *own_buf)
+{
+  client_state &cs = get_client_state ();
+  ULONGEST num;
+  LONGEST val = 0;
+  int err;
+  char *packet = own_buf;
+
+  packet += strlen ("qTV:");
+  unpack_varlen_hex (packet, &num);
+
+  if (cs.current_traceframe >= 0)
+    {
+      err = traceframe_read_tsv ((int) num, &val);
+      if (err)
+	{
+	  strcpy (own_buf, "U");
+	  return;
+	}
+    }
+  /* Only make tsv's be undefined before the first trace run.  After a
+     trace run is over, the user might want to see the last value of
+     the tsv, and it might not be available in a traceframe.  */
+  else if (!tracing && strcmp (tracing_stop_reason, "tnotrun") == 0)
+    {
+      strcpy (own_buf, "U");
+      return;
+    }
+  else
+    val = get_trace_state_variable_value (num);
+
+  sprintf (own_buf, "V%s", phex_nz (val, 0));
+}
+
+/* Clear out the list of readonly regions.  */
+
+static void
+clear_readonly_regions (void)
+{
+  struct readonly_region *roreg;
+
+  while (readonly_regions)
+    {
+      roreg = readonly_regions;
+      readonly_regions = readonly_regions->next;
+      free (roreg);
+    }
+}
+
+/* Parse the collection of address ranges whose contents GDB believes
+   to be unchanging and so can be read directly from target memory
+   even while looking at a traceframe.  */
+
+static void
+cmd_qtro (char *own_buf)
+{
+  ULONGEST start, end;
+  struct readonly_region *roreg;
+  const char *packet = own_buf;
+
+  trace_debug ("Want to mark readonly regions");
+
+  clear_readonly_regions ();
+
+  packet += strlen ("QTro");
+
+  while (*packet == ':')
+    {
+      ++packet;  /* skip a colon */
+      packet = unpack_varlen_hex (packet, &start);
+      ++packet;  /* skip a comma */
+      packet = unpack_varlen_hex (packet, &end);
+
+      roreg = XNEW (struct readonly_region);
+      roreg->start = start;
+      roreg->end = end;
+      roreg->next = readonly_regions;
+      readonly_regions = roreg;
+      trace_debug ("Added readonly region from 0x%s to 0x%s",
+		   paddress (roreg->start), paddress (roreg->end));
+    }
+
+  write_ok (own_buf);
+}
+
+/* Test to see if the given range is in our list of readonly ranges.
+   We only test for being entirely within a range, GDB is not going to
+   send a single memory packet that spans multiple regions.  */
+
+int
+in_readonly_region (CORE_ADDR addr, ULONGEST length)
+{
+  struct readonly_region *roreg;
+
+  for (roreg = readonly_regions; roreg; roreg = roreg->next)
+    if (roreg->start <= addr && (addr + length - 1) <= roreg->end)
+      return 1;
+
+  return 0;
+}
+
+static CORE_ADDR gdb_jump_pad_head;
+
+/* Return the address of the next free jump space.  */
+
+static CORE_ADDR
+get_jump_space_head (void)
+{
+  if (gdb_jump_pad_head == 0)
+    {
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_jump_pad_buffer,
+				      &gdb_jump_pad_head))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "error extracting jump_pad_buffer");
+	}
+    }
+
+  return gdb_jump_pad_head;
+}
+
+/* Reserve USED bytes from the jump space.  */
+
+static void
+claim_jump_space (ULONGEST used)
+{
+  trace_debug ("claim_jump_space reserves %s bytes at %s",
+	       pulongest (used), paddress (gdb_jump_pad_head));
+  gdb_jump_pad_head += used;
+}
+
+static CORE_ADDR trampoline_buffer_head = 0;
+static CORE_ADDR trampoline_buffer_tail;
+
+/* Reserve USED bytes from the trampoline buffer and return the
+   address of the start of the reserved space in TRAMPOLINE.  Returns
+   non-zero if the space is successfully claimed.  */
+
+int
+claim_trampoline_space (ULONGEST used, CORE_ADDR *trampoline)
+{
+  if (!trampoline_buffer_head)
+    {
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer,
+				      &trampoline_buffer_tail))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "error extracting trampoline_buffer");
+	}
+
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer_end,
+				      &trampoline_buffer_head))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "error extracting trampoline_buffer_end");
+	}
+    }
+
+  /* Start claiming space from the top of the trampoline space.  If
+     the space is located at the bottom of the virtual address space,
+     this reduces the possibility that corruption will occur if a null
+     pointer is used to write to memory.  */
+  if (trampoline_buffer_head - trampoline_buffer_tail < used)
+    {
+      trace_debug ("claim_trampoline_space failed to reserve %s bytes",
+		   pulongest (used));
+      return 0;
+    }
+
+  trampoline_buffer_head -= used;
+
+  trace_debug ("claim_trampoline_space reserves %s bytes at %s",
+	       pulongest (used), paddress (trampoline_buffer_head));
+
+  *trampoline = trampoline_buffer_head;
+  return 1;
+}
+
+/* Returns non-zero if there is space allocated for use in trampolines
+   for fast tracepoints.  */
+
+int
+have_fast_tracepoint_trampoline_buffer (char *buf)
+{
+  CORE_ADDR trampoline_end, errbuf;
+
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer_end,
+				  &trampoline_end))
+    {
+      internal_error (__FILE__, __LINE__,
+		      "error extracting trampoline_buffer_end");
+    }
+  
+  if (buf)
+    {
+      buf[0] = '\0';
+      strcpy (buf, "was claiming");
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer_error,
+				  &errbuf))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "error extracting errbuf");
+	}
+
+      read_inferior_memory (errbuf, (unsigned char *) buf, 100);
+    }
+
+  return trampoline_end != 0;
+}
+
+/* Ask the IPA to probe the marker at ADDRESS.  Returns -1 if running
+   the command fails, or 0 otherwise.  If the command ran
+   successfully, but probing the marker failed, ERROUT will be filled
+   with the error to reply to GDB, and -1 is also returned.  This
+   allows directly passing IPA errors to GDB.  */
+
+static int
+probe_marker_at (CORE_ADDR address, char *errout)
+{
+  char cmd[IPA_CMD_BUF_SIZE];
+  int err;
+
+  sprintf (cmd, "probe_marker_at:%s", paddress (address));
+  err = run_inferior_command (cmd, strlen (cmd) + 1);
+
+  if (err == 0)
+    {
+      if (*cmd == 'E')
+	{
+	  strcpy (errout, cmd);
+	  return -1;
+	}
+    }
+
+  return err;
+}
+
+static void
+clone_fast_tracepoint (struct tracepoint *to, const struct tracepoint *from)
+{
+  to->jump_pad = from->jump_pad;
+  to->jump_pad_end = from->jump_pad_end;
+  to->trampoline = from->trampoline;
+  to->trampoline_end = from->trampoline_end;
+  to->adjusted_insn_addr = from->adjusted_insn_addr;
+  to->adjusted_insn_addr_end = from->adjusted_insn_addr_end;
+  to->handle = from->handle;
+
+  gdb_assert (from->handle);
+  inc_ref_fast_tracepoint_jump ((struct fast_tracepoint_jump *) from->handle);
+}
+
+#define MAX_JUMP_SIZE 20
+
+/* Install fast tracepoint.  Return 0 if successful, otherwise return
+   non-zero.  */
+
+static int
+install_fast_tracepoint (struct tracepoint *tpoint, char *errbuf)
+{
+  CORE_ADDR jentry, jump_entry;
+  CORE_ADDR trampoline;
+  CORE_ADDR collect;
+  ULONGEST trampoline_size;
+  int err = 0;
+  /* The jump to the jump pad of the last fast tracepoint
+     installed.  */
+  unsigned char fjump[MAX_JUMP_SIZE];
+  ULONGEST fjump_size;
+
+  if (tpoint->orig_size < target_get_min_fast_tracepoint_insn_len ())
+    {
+      trace_debug ("Requested a fast tracepoint on an instruction "
+		   "that is of less than the minimum length.");
+      return 0;
+    }
+
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_collect_ptr,
+				  &collect))
+    {
+      error ("error extracting gdb_collect_ptr");
+      return 1;
+    }
+
+  jentry = jump_entry = get_jump_space_head ();
+
+  trampoline = 0;
+  trampoline_size = 0;
+
+  /* Install the jump pad.  */
+  err = install_fast_tracepoint_jump_pad (tpoint->obj_addr_on_target,
+					  tpoint->address,
+					  collect,
+					  ipa_sym_addrs.addr_collecting,
+					  tpoint->orig_size,
+					  &jentry,
+					  &trampoline, &trampoline_size,
+					  fjump, &fjump_size,
+					  &tpoint->adjusted_insn_addr,
+					  &tpoint->adjusted_insn_addr_end,
+					  errbuf);
+
+  if (err)
+    return 1;
+
+  /* Wire it in.  */
+  tpoint->handle = set_fast_tracepoint_jump (tpoint->address, fjump,
+					     fjump_size);
+
+  if (tpoint->handle != NULL)
+    {
+      tpoint->jump_pad = jump_entry;
+      tpoint->jump_pad_end = jentry;
+      tpoint->trampoline = trampoline;
+      tpoint->trampoline_end = trampoline + trampoline_size;
+
+      /* Pad to 8-byte alignment.  */
+      jentry = ((jentry + 7) & ~0x7);
+      claim_jump_space (jentry - jump_entry);
+    }
+
+  return 0;
+}
+
+
+/* Install tracepoint TPOINT, and write reply message in OWN_BUF.  */
+
+static void
+install_tracepoint (struct tracepoint *tpoint, char *own_buf)
+{
+  tpoint->handle = NULL;
+  *own_buf = '\0';
+
+  if (tpoint->type == trap_tracepoint)
+    {
+      /* Tracepoints are installed as memory breakpoints.  Just go
+	 ahead and install the trap.  The breakpoints module
+	 handles duplicated breakpoints, and the memory read
+	 routine handles un-patching traps from memory reads.  */
+      tpoint->handle = set_breakpoint_at (tpoint->address,
+					  tracepoint_handler);
+    }
+  else if (tpoint->type == fast_tracepoint || tpoint->type == static_tracepoint)
+    {
+      if (!agent_loaded_p ())
+	{
+	  trace_debug ("Requested a %s tracepoint, but fast "
+		       "tracepoints aren't supported.",
+		       tpoint->type == static_tracepoint ? "static" : "fast");
+	  write_e_ipa_not_loaded (own_buf);
+	  return;
+	}
+      if (tpoint->type == static_tracepoint
+	  && !in_process_agent_supports_ust ())
+	{
+	  trace_debug ("Requested a static tracepoint, but static "
+		       "tracepoints are not supported.");
+	  write_e_ust_not_loaded (own_buf);
+	  return;
+	}
+
+      if (tpoint->type == fast_tracepoint)
+	install_fast_tracepoint (tpoint, own_buf);
+      else
+	{
+	  if (probe_marker_at (tpoint->address, own_buf) == 0)
+	    tpoint->handle = (void *) -1;
+	}
+
+    }
+  else
+    internal_error (__FILE__, __LINE__, "Unknown tracepoint type");
+
+  if (tpoint->handle == NULL)
+    {
+      if (*own_buf == '\0')
+	write_enn (own_buf);
+    }
+  else
+    write_ok (own_buf);
+}
+
+static void download_tracepoint_1 (struct tracepoint *tpoint);
+
+static void
+cmd_qtstart (char *packet)
+{
+  struct tracepoint *tpoint, *prev_ftpoint, *prev_stpoint;
+  CORE_ADDR tpptr = 0, prev_tpptr = 0;
+
+  trace_debug ("Starting the trace");
+
+  /* Pause all threads temporarily while we patch tracepoints.  */
+  pause_all (0);
+
+  /* Get threads out of jump pads.  Safe to do here, since this is a
+     top level command.  And, required to do here, since we're
+     deleting/rewriting jump pads.  */
+
+  stabilize_threads ();
+
+  /* Freeze threads.  */
+  pause_all (1);
+
+  /* Sync the fast tracepoints list in the inferior ftlib.  */
+  if (agent_loaded_p ())
+    download_trace_state_variables ();
+
+  /* No previous fast tpoint yet.  */
+  prev_ftpoint = NULL;
+
+  /* No previous static tpoint yet.  */
+  prev_stpoint = NULL;
+
+  *packet = '\0';
+
+  if (agent_loaded_p ())
+    {
+      /* Tell IPA about the correct tdesc.  */
+      if (write_inferior_integer (ipa_sym_addrs.addr_ipa_tdesc_idx,
+				  target_get_ipa_tdesc_idx ()))
+        error ("Error setting ipa_tdesc_idx variable in lib");
+    }
+
+  /* Start out empty.  */
+  if (agent_loaded_p ())
+    write_inferior_data_pointer (ipa_sym_addrs.addr_tracepoints, 0);
+
+  /* Download and install tracepoints.  */
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    {
+      /* Ensure all the hit counts start at zero.  */
+      tpoint->hit_count = 0;
+      tpoint->traceframe_usage = 0;
+
+      if (tpoint->type == trap_tracepoint)
+	{
+	  /* Tracepoints are installed as memory breakpoints.  Just go
+	     ahead and install the trap.  The breakpoints module
+	     handles duplicated breakpoints, and the memory read
+	     routine handles un-patching traps from memory reads.  */
+	  tpoint->handle = set_breakpoint_at (tpoint->address,
+					      tracepoint_handler);
+	}
+      else if (tpoint->type == fast_tracepoint
+	       || tpoint->type == static_tracepoint)
+	{
+	  if (maybe_write_ipa_not_loaded (packet))
+	    {
+	      trace_debug ("Requested a %s tracepoint, but fast "
+			   "tracepoints aren't supported.",
+			   tpoint->type == static_tracepoint
+			   ? "static" : "fast");
+	      break;
+	    }
+
+	  if (tpoint->type == fast_tracepoint)
+	    {
+	      int use_agent_p
+		= use_agent && agent_capability_check (AGENT_CAPA_FAST_TRACE);
+
+	      if (prev_ftpoint != NULL
+		  && prev_ftpoint->address == tpoint->address)
+		{
+		  if (use_agent_p)
+		    tracepoint_send_agent (tpoint);
+		  else
+		    download_tracepoint_1 (tpoint);
+
+		  clone_fast_tracepoint (tpoint, prev_ftpoint);
+		}
+	      else
+		{
+		  /* Tracepoint is installed successfully?  */
+		  int installed = 0;
+
+		  /* Download and install fast tracepoint by agent.  */
+		  if (use_agent_p)
+		    installed = !tracepoint_send_agent (tpoint);
+		  else
+		    {
+		      download_tracepoint_1 (tpoint);
+		      installed = !install_fast_tracepoint (tpoint, packet);
+		    }
+
+		  if (installed)
+		    prev_ftpoint = tpoint;
+		}
+	    }
+	  else
+	    {
+	      if (!in_process_agent_supports_ust ())
+		{
+		  trace_debug ("Requested a static tracepoint, but static "
+			       "tracepoints are not supported.");
+		  break;
+		}
+
+	      download_tracepoint_1 (tpoint);
+	      /* Can only probe a given marker once.  */
+	      if (prev_stpoint != NULL
+		  && prev_stpoint->address == tpoint->address)
+		tpoint->handle = (void *) -1;
+	      else
+		{
+		  if (probe_marker_at (tpoint->address, packet) == 0)
+		    {
+		      tpoint->handle = (void *) -1;
+
+		      /* So that we can handle multiple static tracepoints
+			 at the same address easily.  */
+		      prev_stpoint = tpoint;
+		    }
+		}
+	    }
+
+	  prev_tpptr = tpptr;
+	  tpptr = tpoint->obj_addr_on_target;
+
+	  if (tpoint == tracepoints)
+	    /* First object in list, set the head pointer in the
+	       inferior.  */
+	    write_inferior_data_pointer (ipa_sym_addrs.addr_tracepoints, tpptr);
+	  else
+	    write_inferior_data_pointer (prev_tpptr
+					 + offsetof (struct tracepoint, next),
+					 tpptr);
+	}
+
+      /* Any failure in the inner loop is sufficient cause to give
+	 up.  */
+      if (tpoint->handle == NULL)
+	break;
+    }
+
+  /* Any error in tracepoint insertion is unacceptable; better to
+     address the problem now, than end up with a useless or misleading
+     trace run.  */
+  if (tpoint != NULL)
+    {
+      clear_installed_tracepoints ();
+      if (*packet == '\0')
+	write_enn (packet);
+      unpause_all (1);
+      return;
+    }
+
+  stopping_tracepoint = NULL;
+  trace_buffer_is_full = 0;
+  expr_eval_result = expr_eval_no_error;
+  error_tracepoint = NULL;
+  tracing_start_time = get_timestamp ();
+
+  /* Tracing is now active, hits will now start being logged.  */
+  tracing = 1;
+
+  if (agent_loaded_p ())
+    {
+      if (write_inferior_integer (ipa_sym_addrs.addr_tracing, 1))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "Error setting tracing variable in lib");
+	}
+
+      if (write_inferior_data_pointer (ipa_sym_addrs.addr_stopping_tracepoint,
+				       0))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "Error clearing stopping_tracepoint variable"
+			  " in lib");
+	}
+
+      if (write_inferior_integer (ipa_sym_addrs.addr_trace_buffer_is_full, 0))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "Error clearing trace_buffer_is_full variable"
+			  " in lib");
+	}
+
+      stop_tracing_bkpt = set_breakpoint_at (ipa_sym_addrs.addr_stop_tracing,
+					     stop_tracing_handler);
+      if (stop_tracing_bkpt == NULL)
+	error ("Error setting stop_tracing breakpoint");
+
+      flush_trace_buffer_bkpt
+	= set_breakpoint_at (ipa_sym_addrs.addr_flush_trace_buffer,
+			     flush_trace_buffer_handler);
+      if (flush_trace_buffer_bkpt == NULL)
+	error ("Error setting flush_trace_buffer breakpoint");
+    }
+
+  unpause_all (1);
+
+  write_ok (packet);
+}
+
+/* End a tracing run, filling in a stop reason to report back to GDB,
+   and removing the tracepoints from the code.  */
+
+void
+stop_tracing (void)
+{
+  if (!tracing)
+    {
+      trace_debug ("Tracing is already off, ignoring");
+      return;
+    }
+
+  trace_debug ("Stopping the trace");
+
+  /* Pause all threads before removing fast jumps from memory,
+     breakpoints, and touching IPA state variables (inferior memory).
+     Some thread may hit the internal tracing breakpoints, or be
+     collecting this moment, but that's ok, we don't release the
+     tpoint object's memory or the jump pads here (we only do that
+     when we're sure we can move all threads out of the jump pads).
+     We can't now, since we may be getting here due to the inferior
+     agent calling us.  */
+  pause_all (1);
+
+  /* Stop logging. Tracepoints can still be hit, but they will not be
+     recorded.  */
+  tracing = 0;
+  if (agent_loaded_p ())
+    {
+      if (write_inferior_integer (ipa_sym_addrs.addr_tracing, 0))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "Error clearing tracing variable in lib");
+	}
+    }
+
+  tracing_stop_time = get_timestamp ();
+  tracing_stop_reason = "t???";
+  tracing_stop_tpnum = 0;
+  if (stopping_tracepoint)
+    {
+      trace_debug ("Stopping the trace because "
+		   "tracepoint %d was hit %" PRIu64 " times",
+		   stopping_tracepoint->number,
+		   stopping_tracepoint->pass_count);
+      tracing_stop_reason = "tpasscount";
+      tracing_stop_tpnum = stopping_tracepoint->number;
+    }
+  else if (trace_buffer_is_full)
+    {
+      trace_debug ("Stopping the trace because the trace buffer is full");
+      tracing_stop_reason = "tfull";
+    }
+  else if (expr_eval_result != expr_eval_no_error)
+    {
+      trace_debug ("Stopping the trace because of an expression eval error");
+      tracing_stop_reason = eval_result_names[expr_eval_result];
+      tracing_stop_tpnum = error_tracepoint->number;
+    }
+#ifndef IN_PROCESS_AGENT
+  else if (!gdb_connected ())
+    {
+      trace_debug ("Stopping the trace because GDB disconnected");
+      tracing_stop_reason = "tdisconnected";
+    }
+#endif
+  else
+    {
+      trace_debug ("Stopping the trace because of a tstop command");
+      tracing_stop_reason = "tstop";
+    }
+
+  stopping_tracepoint = NULL;
+  error_tracepoint = NULL;
+
+  /* Clear out the tracepoints.  */
+  clear_installed_tracepoints ();
+
+  if (agent_loaded_p ())
+    {
+      /* Pull in fast tracepoint trace frames from the inferior lib
+	 buffer into our buffer, even if our buffer is already full,
+	 because we want to present the full number of created frames
+	 in addition to what fit in the trace buffer.  */
+      upload_fast_traceframes ();
+    }
+
+  if (stop_tracing_bkpt != NULL)
+    {
+      delete_breakpoint (stop_tracing_bkpt);
+      stop_tracing_bkpt = NULL;
+    }
+
+  if (flush_trace_buffer_bkpt != NULL)
+    {
+      delete_breakpoint (flush_trace_buffer_bkpt);
+      flush_trace_buffer_bkpt = NULL;
+    }
+
+  unpause_all (1);
+}
+
+static int
+stop_tracing_handler (CORE_ADDR addr)
+{
+  trace_debug ("lib hit stop_tracing");
+
+  /* Don't actually handle it here.  When we stop tracing we remove
+     breakpoints from the inferior, and that is not allowed in a
+     breakpoint handler (as the caller is walking the breakpoint
+     list).  */
+  return 0;
+}
+
+static int
+flush_trace_buffer_handler (CORE_ADDR addr)
+{
+  trace_debug ("lib hit flush_trace_buffer");
+  return 0;
+}
+
+static void
+cmd_qtstop (char *packet)
+{
+  stop_tracing ();
+  write_ok (packet);
+}
+
+static void
+cmd_qtdisconnected (char *own_buf)
+{
+  ULONGEST setting;
+  char *packet = own_buf;
+
+  packet += strlen ("QTDisconnected:");
+
+  unpack_varlen_hex (packet, &setting);
+
+  write_ok (own_buf);
+
+  disconnected_tracing = setting;
+}
+
+static void
+cmd_qtframe (char *own_buf)
+{
+  client_state &cs = get_client_state ();
+  ULONGEST frame, pc, lo, hi, num;
+  int tfnum, tpnum;
+  struct traceframe *tframe;
+  const char *packet = own_buf;
+
+  packet += strlen ("QTFrame:");
+
+  if (startswith (packet, "pc:"))
+    {
+      packet += strlen ("pc:");
+      unpack_varlen_hex (packet, &pc);
+      trace_debug ("Want to find next traceframe at pc=0x%s", paddress (pc));
+      tframe = find_next_traceframe_in_range (pc, pc, 1, &tfnum);
+    }
+  else if (startswith (packet, "range:"))
+    {
+      packet += strlen ("range:");
+      packet = unpack_varlen_hex (packet, &lo);
+      ++packet;
+      unpack_varlen_hex (packet, &hi);
+      trace_debug ("Want to find next traceframe in the range 0x%s to 0x%s",
+		   paddress (lo), paddress (hi));
+      tframe = find_next_traceframe_in_range (lo, hi, 1, &tfnum);
+    }
+  else if (startswith (packet, "outside:"))
+    {
+      packet += strlen ("outside:");
+      packet = unpack_varlen_hex (packet, &lo);
+      ++packet;
+      unpack_varlen_hex (packet, &hi);
+      trace_debug ("Want to find next traceframe "
+		   "outside the range 0x%s to 0x%s",
+		   paddress (lo), paddress (hi));
+      tframe = find_next_traceframe_in_range (lo, hi, 0, &tfnum);
+    }
+  else if (startswith (packet, "tdp:"))
+    {
+      packet += strlen ("tdp:");
+      unpack_varlen_hex (packet, &num);
+      tpnum = (int) num;
+      trace_debug ("Want to find next traceframe for tracepoint %d", tpnum);
+      tframe = find_next_traceframe_by_tracepoint (tpnum, &tfnum);
+    }
+  else
+    {
+      unpack_varlen_hex (packet, &frame);
+      tfnum = (int) frame;
+      if (tfnum == -1)
+	{
+	  trace_debug ("Want to stop looking at traceframes");
+	  cs.current_traceframe = -1;
+	  write_ok (own_buf);
+	  return;
+	}
+      trace_debug ("Want to look at traceframe %d", tfnum);
+      tframe = find_traceframe (tfnum);
+    }
+
+  if (tframe)
+    {
+      cs.current_traceframe = tfnum;
+      sprintf (own_buf, "F%xT%x", tfnum, tframe->tpnum);
+    }
+  else
+    sprintf (own_buf, "F-1");
+}
+
+static void
+cmd_qtstatus (char *packet)
+{
+  char *stop_reason_rsp = NULL;
+  char *buf1, *buf2, *buf3;
+  const char *str;
+  int slen;
+
+  /* Translate the plain text of the notes back into hex for
+     transmission.  */
+
+  str = (tracing_user_name ? tracing_user_name : "");
+  slen = strlen (str);
+  buf1 = (char *) alloca (slen * 2 + 1);
+  bin2hex ((gdb_byte *) str, buf1, slen);
+
+  str = (tracing_notes ? tracing_notes : "");
+  slen = strlen (str);
+  buf2 = (char *) alloca (slen * 2 + 1);
+  bin2hex ((gdb_byte *) str, buf2, slen);
+
+  str = (tracing_stop_note ? tracing_stop_note : "");
+  slen = strlen (str);
+  buf3 = (char *) alloca (slen * 2 + 1);
+  bin2hex ((gdb_byte *) str, buf3, slen);
+
+  trace_debug ("Returning trace status as %d, stop reason %s",
+	       tracing, tracing_stop_reason);
+
+  if (agent_loaded_p ())
+    {
+      pause_all (1);
+
+      upload_fast_traceframes ();
+
+      unpause_all (1);
+   }
+
+  stop_reason_rsp = (char *) tracing_stop_reason;
+
+  /* The user visible error string in terror needs to be hex encoded.
+     We leave it as plain string in `tracing_stop_reason' to ease
+     debugging.  */
+  if (startswith (stop_reason_rsp, "terror:"))
+    {
+      const char *result_name;
+      int hexstr_len;
+      char *p;
+
+      result_name = stop_reason_rsp + strlen ("terror:");
+      hexstr_len = strlen (result_name) * 2;
+      p = stop_reason_rsp
+	= (char *) alloca (strlen ("terror:") + hexstr_len + 1);
+      strcpy (p, "terror:");
+      p += strlen (p);
+      bin2hex ((gdb_byte *) result_name, p, strlen (result_name));
+    }
+
+  /* If this was a forced stop, include any stop note that was supplied.  */
+  if (strcmp (stop_reason_rsp, "tstop") == 0)
+    {
+      stop_reason_rsp = (char *) alloca (strlen ("tstop:") + strlen (buf3) + 1);
+      strcpy (stop_reason_rsp, "tstop:");
+      strcat (stop_reason_rsp, buf3);
+    }
+
+  sprintf (packet,
+	   "T%d;"
+	   "%s:%x;"
+	   "tframes:%x;tcreated:%x;"
+	   "tfree:%x;tsize:%s;"
+	   "circular:%d;"
+	   "disconn:%d;"
+	   "starttime:%s;stoptime:%s;"
+	   "username:%s;notes:%s:",
+	   tracing ? 1 : 0,
+	   stop_reason_rsp, tracing_stop_tpnum,
+	   traceframe_count, traceframes_created,
+	   free_space (), phex_nz (trace_buffer_hi - trace_buffer_lo, 0),
+	   circular_trace_buffer,
+	   disconnected_tracing,
+	   phex_nz (tracing_start_time, sizeof (tracing_start_time)),
+	   phex_nz (tracing_stop_time, sizeof (tracing_stop_time)),
+	   buf1, buf2);
+}
+
+static void
+cmd_qtp (char *own_buf)
+{
+  ULONGEST num, addr;
+  struct tracepoint *tpoint;
+  const char *packet = own_buf;
+
+  packet += strlen ("qTP:");
+
+  packet = unpack_varlen_hex (packet, &num);
+  ++packet; /* skip a colon */
+  packet = unpack_varlen_hex (packet, &addr);
+
+  /* See if we already have this tracepoint.  */
+  tpoint = find_tracepoint (num, addr);
+
+  if (!tpoint)
+    {
+      trace_debug ("Tracepoint error: tracepoint %d at 0x%s not found",
+		   (int) num, paddress (addr));
+      write_enn (own_buf);
+      return;
+    }
+
+  sprintf (own_buf, "V%" PRIu64 ":%" PRIu64 "", tpoint->hit_count,
+	   tpoint->traceframe_usage);
+}
+
+/* State variables to help return all the tracepoint bits.  */
+static struct tracepoint *cur_tpoint;
+static unsigned int cur_action;
+static unsigned int cur_step_action;
+static struct source_string *cur_source_string;
+static struct trace_state_variable *cur_tsv;
+
+/* Compose a response that is an imitation of the syntax by which the
+   tracepoint was originally downloaded.  */
+
+static void
+response_tracepoint (char *packet, struct tracepoint *tpoint)
+{
+  char *buf;
+
+  sprintf (packet, "T%x:%s:%c:%" PRIx64 ":%" PRIx64, tpoint->number,
+	   paddress (tpoint->address),
+	   (tpoint->enabled ? 'E' : 'D'), tpoint->step_count,
+	   tpoint->pass_count);
+  if (tpoint->type == fast_tracepoint)
+    sprintf (packet + strlen (packet), ":F%x", tpoint->orig_size);
+  else if (tpoint->type == static_tracepoint)
+    sprintf (packet + strlen (packet), ":S");
+
+  if (tpoint->cond)
+    {
+      buf = gdb_unparse_agent_expr (tpoint->cond);
+      sprintf (packet + strlen (packet), ":X%x,%s",
+	       tpoint->cond->length, buf);
+      free (buf);
+    }
+}
+
+/* Compose a response that is an imitation of the syntax by which the
+   tracepoint action was originally downloaded (with the difference
+   that due to the way we store the actions, this will output a packet
+   per action, while GDB could have combined more than one action
+   per-packet.  */
+
+static void
+response_action (char *packet, struct tracepoint *tpoint,
+		 char *taction, int step)
+{
+  sprintf (packet, "%c%x:%s:%s",
+	   (step ? 'S' : 'A'), tpoint->number, paddress (tpoint->address),
+	   taction);
+}
+
+/* Compose a response that is an imitation of the syntax by which the
+   tracepoint source piece was originally downloaded.  */
+
+static void
+response_source (char *packet,
+		 struct tracepoint *tpoint, struct source_string *src)
+{
+  char *buf;
+  int len;
+
+  len = strlen (src->str);
+  buf = (char *) alloca (len * 2 + 1);
+  bin2hex ((gdb_byte *) src->str, buf, len);
+
+  sprintf (packet, "Z%x:%s:%s:%x:%x:%s",
+	   tpoint->number, paddress (tpoint->address),
+	   src->type, 0, len, buf);
+}
+
+/* Return the first piece of tracepoint definition, and initialize the
+   state machine that will iterate through all the tracepoint
+   bits.  */
+
+static void
+cmd_qtfp (char *packet)
+{
+  trace_debug ("Returning first tracepoint definition piece");
+
+  cur_tpoint = tracepoints;
+  cur_action = cur_step_action = 0;
+  cur_source_string = NULL;
+
+  if (cur_tpoint)
+    response_tracepoint (packet, cur_tpoint);
+  else
+    strcpy (packet, "l");
+}
+
+/* Return additional pieces of tracepoint definition.  Each action and
+   stepping action must go into its own packet, because of packet size
+   limits, and so we use state variables to deliver one piece at a
+   time.  */
+
+static void
+cmd_qtsp (char *packet)
+{
+  trace_debug ("Returning subsequent tracepoint definition piece");
+
+  if (!cur_tpoint)
+    {
+      /* This case would normally never occur, but be prepared for
+	 GDB misbehavior.  */
+      strcpy (packet, "l");
+    }
+  else if (cur_action < cur_tpoint->numactions)
+    {
+      response_action (packet, cur_tpoint,
+		       cur_tpoint->actions_str[cur_action], 0);
+      ++cur_action;
+    }
+  else if (cur_step_action < cur_tpoint->num_step_actions)
+    {
+      response_action (packet, cur_tpoint,
+		       cur_tpoint->step_actions_str[cur_step_action], 1);
+      ++cur_step_action;
+    }
+  else if ((cur_source_string
+	    ? cur_source_string->next
+	    : cur_tpoint->source_strings))
+    {
+      if (cur_source_string)
+	cur_source_string = cur_source_string->next;
+      else
+	cur_source_string = cur_tpoint->source_strings;
+      response_source (packet, cur_tpoint, cur_source_string);
+    }
+  else
+    {
+      cur_tpoint = cur_tpoint->next;
+      cur_action = cur_step_action = 0;
+      cur_source_string = NULL;
+      if (cur_tpoint)
+	response_tracepoint (packet, cur_tpoint);
+      else
+	strcpy (packet, "l");
+    }
+}
+
+/* Compose a response that is an imitation of the syntax by which the
+   trace state variable was originally downloaded.  */
+
+static void
+response_tsv (char *packet, struct trace_state_variable *tsv)
+{
+  char *buf = (char *) "";
+  int namelen;
+
+  if (tsv->name)
+    {
+      namelen = strlen (tsv->name);
+      buf = (char *) alloca (namelen * 2 + 1);
+      bin2hex ((gdb_byte *) tsv->name, buf, namelen);
+    }
+
+  sprintf (packet, "%x:%s:%x:%s", tsv->number, phex_nz (tsv->initial_value, 0),
+	   tsv->getter ? 1 : 0, buf);
+}
+
+/* Return the first trace state variable definition, and initialize
+   the state machine that will iterate through all the tsv bits.  */
+
+static void
+cmd_qtfv (char *packet)
+{
+  trace_debug ("Returning first trace state variable definition");
+
+  cur_tsv = trace_state_variables;
+
+  if (cur_tsv)
+    response_tsv (packet, cur_tsv);
+  else
+    strcpy (packet, "l");
+}
+
+/* Return additional trace state variable definitions. */
+
+static void
+cmd_qtsv (char *packet)
+{
+  trace_debug ("Returning additional trace state variable definition");
+
+  if (cur_tsv)
+    {
+      cur_tsv = cur_tsv->next;
+      if (cur_tsv)
+	response_tsv (packet, cur_tsv);
+      else
+	strcpy (packet, "l");
+    }
+  else
+    strcpy (packet, "l");
+}
+
+/* Return the first static tracepoint marker, and initialize the state
+   machine that will iterate through all the static tracepoints
+   markers.  */
+
+static void
+cmd_qtfstm (char *packet)
+{
+  if (!maybe_write_ipa_ust_not_loaded (packet))
+    run_inferior_command (packet, strlen (packet) + 1);
+}
+
+/* Return additional static tracepoints markers.  */
+
+static void
+cmd_qtsstm (char *packet)
+{
+  if (!maybe_write_ipa_ust_not_loaded (packet))
+    run_inferior_command (packet, strlen (packet) + 1);
+}
+
+/* Return the definition of the static tracepoint at a given address.
+   Result packet is the same as qTsST's.  */
+
+static void
+cmd_qtstmat (char *packet)
+{
+  if (!maybe_write_ipa_ust_not_loaded (packet))
+    run_inferior_command (packet, strlen (packet) + 1);
+}
+
+/* Sent the agent a command to close it.  */
+
+void
+gdb_agent_about_to_close (int pid)
+{
+  char buf[IPA_CMD_BUF_SIZE];
+
+  if (!maybe_write_ipa_not_loaded (buf))
+    {
+      struct thread_info *saved_thread;
+
+      saved_thread = current_thread;
+
+      /* Find any thread which belongs to process PID.  */
+      current_thread = find_any_thread_of_pid (pid);
+
+      strcpy (buf, "close");
+
+      run_inferior_command (buf, strlen (buf) + 1);
+
+      current_thread = saved_thread;
+    }
+}
+
+/* Return the minimum instruction size needed for fast tracepoints as a
+   hexadecimal number.  */
+
+static void
+cmd_qtminftpilen (char *packet)
+{
+  if (current_thread == NULL)
+    {
+      /* Indicate that the minimum length is currently unknown.  */
+      strcpy (packet, "0");
+      return;
+    }
+
+  sprintf (packet, "%x", target_get_min_fast_tracepoint_insn_len ());
+}
+
+/* Respond to qTBuffer packet with a block of raw data from the trace
+   buffer.  GDB may ask for a lot, but we are allowed to reply with
+   only as much as will fit within packet limits or whatever.  */
+
+static void
+cmd_qtbuffer (char *own_buf)
+{
+  ULONGEST offset, num, tot;
+  unsigned char *tbp;
+  const char *packet = own_buf;
+
+  packet += strlen ("qTBuffer:");
+
+  packet = unpack_varlen_hex (packet, &offset);
+  ++packet; /* skip a comma */
+  unpack_varlen_hex (packet, &num);
+
+  trace_debug ("Want to get trace buffer, %d bytes at offset 0x%s",
+	       (int) num, phex_nz (offset, 0));
+
+  tot = (trace_buffer_hi - trace_buffer_lo) - free_space ();
+
+  /* If we're right at the end, reply specially that we're done.  */
+  if (offset == tot)
+    {
+      strcpy (own_buf, "l");
+      return;
+    }
+
+  /* Object to any other out-of-bounds request.  */
+  if (offset > tot)
+    {
+      write_enn (own_buf);
+      return;
+    }
+
+  /* Compute the pointer corresponding to the given offset, accounting
+     for wraparound.  */
+  tbp = trace_buffer_start + offset;
+  if (tbp >= trace_buffer_wrap)
+    tbp -= (trace_buffer_wrap - trace_buffer_lo);
+
+  /* Trim to the remaining bytes if we're close to the end.  */
+  if (num > tot - offset)
+    num = tot - offset;
+
+  /* Trim to available packet size.  */
+  if (num >= (PBUFSIZ - 16) / 2 )
+    num = (PBUFSIZ - 16) / 2;
+
+  bin2hex (tbp, own_buf, num);
+}
+
+static void
+cmd_bigqtbuffer_circular (char *own_buf)
+{
+  ULONGEST val;
+  char *packet = own_buf;
+
+  packet += strlen ("QTBuffer:circular:");
+
+  unpack_varlen_hex (packet, &val);
+  circular_trace_buffer = val;
+  trace_debug ("Trace buffer is now %s",
+	       circular_trace_buffer ? "circular" : "linear");
+  write_ok (own_buf);
+}
+
+static void
+cmd_bigqtbuffer_size (char *own_buf)
+{
+  ULONGEST val;
+  LONGEST sval;
+  char *packet = own_buf;
+
+  /* Can't change the size during a tracing run.  */
+  if (tracing)
+    {
+      write_enn (own_buf);
+      return;
+    }
+
+  packet += strlen ("QTBuffer:size:");
+
+  /* -1 is sent as literal "-1".  */
+  if (strcmp (packet, "-1") == 0)
+    sval = DEFAULT_TRACE_BUFFER_SIZE;
+  else
+    {
+      unpack_varlen_hex (packet, &val);
+      sval = (LONGEST) val;
+    }
+
+  init_trace_buffer (sval);
+  trace_debug ("Trace buffer is now %s bytes",
+	       plongest (trace_buffer_size));
+  write_ok (own_buf);
+}
+
+static void
+cmd_qtnotes (char *own_buf)
+{
+  size_t nbytes;
+  char *saved, *user, *notes, *stopnote;
+  char *packet = own_buf;
+
+  packet += strlen ("QTNotes:");
+
+  while (*packet)
+    {
+      if (startswith (packet, "user:"))
+	{
+	  packet += strlen ("user:");
+	  saved = packet;
+	  packet = strchr (packet, ';');
+	  nbytes = (packet - saved) / 2;
+	  user = (char *) xmalloc (nbytes + 1);
+	  nbytes = hex2bin (saved, (gdb_byte *) user, nbytes);
+	  user[nbytes] = '\0';
+	  ++packet; /* skip the semicolon */
+	  trace_debug ("User is '%s'", user);
+	  xfree (tracing_user_name);
+	  tracing_user_name = user;
+	}
+      else if (startswith (packet, "notes:"))
+	{
+	  packet += strlen ("notes:");
+	  saved = packet;
+	  packet = strchr (packet, ';');
+	  nbytes = (packet - saved) / 2;
+	  notes = (char *) xmalloc (nbytes + 1);
+	  nbytes = hex2bin (saved, (gdb_byte *) notes, nbytes);
+	  notes[nbytes] = '\0';
+	  ++packet; /* skip the semicolon */
+	  trace_debug ("Notes is '%s'", notes);
+	  xfree (tracing_notes);
+	  tracing_notes = notes;
+	}
+      else if (startswith (packet, "tstop:"))
+	{
+	  packet += strlen ("tstop:");
+	  saved = packet;
+	  packet = strchr (packet, ';');
+	  nbytes = (packet - saved) / 2;
+	  stopnote = (char *) xmalloc (nbytes + 1);
+	  nbytes = hex2bin (saved, (gdb_byte *) stopnote, nbytes);
+	  stopnote[nbytes] = '\0';
+	  ++packet; /* skip the semicolon */
+	  trace_debug ("tstop note is '%s'", stopnote);
+	  xfree (tracing_stop_note);
+	  tracing_stop_note = stopnote;
+	}
+      else
+	break;
+    }
+
+  write_ok (own_buf);
+}
+
+int
+handle_tracepoint_general_set (char *packet)
+{
+  if (strcmp ("QTinit", packet) == 0)
+    {
+      cmd_qtinit (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTDP:"))
+    {
+      cmd_qtdp (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTDPsrc:"))
+    {
+      cmd_qtdpsrc (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTEnable:"))
+    {
+      cmd_qtenable_disable (packet, 1);
+      return 1;
+    }
+  else if (startswith (packet, "QTDisable:"))
+    {
+      cmd_qtenable_disable (packet, 0);
+      return 1;
+    }
+  else if (startswith (packet, "QTDV:"))
+    {
+      cmd_qtdv (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTro:"))
+    {
+      cmd_qtro (packet);
+      return 1;
+    }
+  else if (strcmp ("QTStart", packet) == 0)
+    {
+      cmd_qtstart (packet);
+      return 1;
+    }
+  else if (strcmp ("QTStop", packet) == 0)
+    {
+      cmd_qtstop (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTDisconnected:"))
+    {
+      cmd_qtdisconnected (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTFrame:"))
+    {
+      cmd_qtframe (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTBuffer:circular:"))
+    {
+      cmd_bigqtbuffer_circular (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTBuffer:size:"))
+    {
+      cmd_bigqtbuffer_size (packet);
+      return 1;
+    }
+  else if (startswith (packet, "QTNotes:"))
+    {
+      cmd_qtnotes (packet);
+      return 1;
+    }
+
+  return 0;
+}
+
+int
+handle_tracepoint_query (char *packet)
+{
+  if (strcmp ("qTStatus", packet) == 0)
+    {
+      cmd_qtstatus (packet);
+      return 1;
+    }
+  else if (startswith (packet, "qTP:"))
+    {
+      cmd_qtp (packet);
+      return 1;
+    }
+  else if (strcmp ("qTfP", packet) == 0)
+    {
+      cmd_qtfp (packet);
+      return 1;
+    }
+  else if (strcmp ("qTsP", packet) == 0)
+    {
+      cmd_qtsp (packet);
+      return 1;
+    }
+  else if (strcmp ("qTfV", packet) == 0)
+    {
+      cmd_qtfv (packet);
+      return 1;
+    }
+  else if (strcmp ("qTsV", packet) == 0)
+    {
+      cmd_qtsv (packet);
+      return 1;
+    }
+  else if (startswith (packet, "qTV:"))
+    {
+      cmd_qtv (packet);
+      return 1;
+    }
+  else if (startswith (packet, "qTBuffer:"))
+    {
+      cmd_qtbuffer (packet);
+      return 1;
+    }
+  else if (strcmp ("qTfSTM", packet) == 0)
+    {
+      cmd_qtfstm (packet);
+      return 1;
+    }
+  else if (strcmp ("qTsSTM", packet) == 0)
+    {
+      cmd_qtsstm (packet);
+      return 1;
+    }
+  else if (startswith (packet, "qTSTMat:"))
+    {
+      cmd_qtstmat (packet);
+      return 1;
+    }
+  else if (strcmp ("qTMinFTPILen", packet) == 0)
+    {
+      cmd_qtminftpilen (packet);
+      return 1;
+    }
+
+  return 0;
+}
+
+#endif
+#ifndef IN_PROCESS_AGENT
+
+/* Call this when thread TINFO has hit the tracepoint defined by
+   TP_NUMBER and TP_ADDRESS, and that tracepoint has a while-stepping
+   action.  This adds a while-stepping collecting state item to the
+   threads' collecting state list, so that we can keep track of
+   multiple simultaneous while-stepping actions being collected by the
+   same thread.  This can happen in cases like:
+
+    ff0001  INSN1 <-- TP1, while-stepping 10 collect $regs
+    ff0002  INSN2
+    ff0003  INSN3 <-- TP2, collect $regs
+    ff0004  INSN4 <-- TP3, while-stepping 10 collect $regs
+    ff0005  INSN5
+
+   Notice that when instruction INSN5 is reached, the while-stepping
+   actions of both TP1 and TP3 are still being collected, and that TP2
+   had been collected meanwhile.  The whole range of ff0001-ff0005
+   should be single-stepped, due to at least TP1's while-stepping
+   action covering the whole range.  */
+
+static void
+add_while_stepping_state (struct thread_info *tinfo,
+			  int tp_number, CORE_ADDR tp_address)
+{
+  struct wstep_state *wstep = XNEW (struct wstep_state);
+
+  wstep->next = tinfo->while_stepping;
+
+  wstep->tp_number = tp_number;
+  wstep->tp_address = tp_address;
+  wstep->current_step = 0;
+
+  tinfo->while_stepping = wstep;
+}
+
+/* Release the while-stepping collecting state WSTEP.  */
+
+static void
+release_while_stepping_state (struct wstep_state *wstep)
+{
+  free (wstep);
+}
+
+/* Release all while-stepping collecting states currently associated
+   with thread TINFO.  */
+
+void
+release_while_stepping_state_list (struct thread_info *tinfo)
+{
+  struct wstep_state *head;
+
+  while (tinfo->while_stepping)
+    {
+      head = tinfo->while_stepping;
+      tinfo->while_stepping = head->next;
+      release_while_stepping_state (head);
+    }
+}
+
+/* If TINFO was handling a 'while-stepping' action, the step has
+   finished, so collect any step data needed, and check if any more
+   steps are required.  Return true if the thread was indeed
+   collecting tracepoint data, false otherwise.  */
+
+int
+tracepoint_finished_step (struct thread_info *tinfo, CORE_ADDR stop_pc)
+{
+  struct tracepoint *tpoint;
+  struct wstep_state *wstep;
+  struct wstep_state **wstep_link;
+  struct trap_tracepoint_ctx ctx;
+
+  /* Pull in fast tracepoint trace frames from the inferior lib buffer into
+     our buffer.  */
+  if (agent_loaded_p ())
+    upload_fast_traceframes ();
+
+  /* Check if we were indeed collecting data for one of more
+     tracepoints with a 'while-stepping' count.  */
+  if (tinfo->while_stepping == NULL)
+    return 0;
+
+  if (!tracing)
+    {
+      /* We're not even tracing anymore.  Stop this thread from
+	 collecting.  */
+      release_while_stepping_state_list (tinfo);
+
+      /* The thread had stopped due to a single-step request indeed
+	 explained by a tracepoint.  */
+      return 1;
+    }
+
+  wstep = tinfo->while_stepping;
+  wstep_link = &tinfo->while_stepping;
+
+  trace_debug ("Thread %s finished a single-step for tracepoint %d at 0x%s",
+	       target_pid_to_str (tinfo->id),
+	       wstep->tp_number, paddress (wstep->tp_address));
+
+  ctx.base.type = trap_tracepoint;
+  ctx.regcache = get_thread_regcache (tinfo, 1);
+
+  while (wstep != NULL)
+    {
+      tpoint = find_tracepoint (wstep->tp_number, wstep->tp_address);
+      if (tpoint == NULL)
+	{
+	  trace_debug ("NO TRACEPOINT %d at 0x%s FOR THREAD %s!",
+		       wstep->tp_number, paddress (wstep->tp_address),
+		       target_pid_to_str (tinfo->id));
+
+	  /* Unlink.  */
+	  *wstep_link = wstep->next;
+	  release_while_stepping_state (wstep);
+	  wstep = *wstep_link;
+	  continue;
+	}
+
+      /* We've just finished one step.  */
+      ++wstep->current_step;
+
+      /* Collect data.  */
+      collect_data_at_step ((struct tracepoint_hit_ctx *) &ctx,
+			    stop_pc, tpoint, wstep->current_step);
+
+      if (wstep->current_step >= tpoint->step_count)
+	{
+	  /* The requested numbers of steps have occurred.  */
+	  trace_debug ("Thread %s done stepping for tracepoint %d at 0x%s",
+		       target_pid_to_str (tinfo->id),
+		       wstep->tp_number, paddress (wstep->tp_address));
+
+	  /* Unlink the wstep.  */
+	  *wstep_link = wstep->next;
+	  release_while_stepping_state (wstep);
+	  wstep = *wstep_link;
+
+	  /* Only check the hit count now, which ensure that we do all
+	     our stepping before stopping the run.  */
+	  if (tpoint->pass_count > 0
+	      && tpoint->hit_count >= tpoint->pass_count
+	      && stopping_tracepoint == NULL)
+	    stopping_tracepoint = tpoint;
+	}
+      else
+	{
+	  /* Keep single-stepping until the requested numbers of steps
+	     have occurred.  */
+	  wstep_link = &wstep->next;
+	  wstep = *wstep_link;
+	}
+
+      if (stopping_tracepoint
+	  || trace_buffer_is_full
+	  || expr_eval_result != expr_eval_no_error)
+	{
+	  stop_tracing ();
+	  break;
+	}
+    }
+
+  return 1;
+}
+
+/* Handle any internal tracing control breakpoint hits.  That means,
+   pull traceframes from the IPA to our buffer, and syncing both
+   tracing agents when the IPA's tracing stops for some reason.  */
+
+int
+handle_tracepoint_bkpts (struct thread_info *tinfo, CORE_ADDR stop_pc)
+{
+  /* Pull in fast tracepoint trace frames from the inferior in-process
+     agent's buffer into our buffer.  */
+
+  if (!agent_loaded_p ())
+    return 0;
+
+  upload_fast_traceframes ();
+
+  /* Check if the in-process agent had decided we should stop
+     tracing.  */
+  if (stop_pc == ipa_sym_addrs.addr_stop_tracing)
+    {
+      int ipa_trace_buffer_is_full;
+      CORE_ADDR ipa_stopping_tracepoint;
+      int ipa_expr_eval_result;
+      CORE_ADDR ipa_error_tracepoint;
+
+      trace_debug ("lib stopped at stop_tracing");
+
+      read_inferior_integer (ipa_sym_addrs.addr_trace_buffer_is_full,
+			     &ipa_trace_buffer_is_full);
+
+      read_inferior_data_pointer (ipa_sym_addrs.addr_stopping_tracepoint,
+				  &ipa_stopping_tracepoint);
+      write_inferior_data_pointer (ipa_sym_addrs.addr_stopping_tracepoint, 0);
+
+      read_inferior_data_pointer (ipa_sym_addrs.addr_error_tracepoint,
+				  &ipa_error_tracepoint);
+      write_inferior_data_pointer (ipa_sym_addrs.addr_error_tracepoint, 0);
+
+      read_inferior_integer (ipa_sym_addrs.addr_expr_eval_result,
+			     &ipa_expr_eval_result);
+      write_inferior_integer (ipa_sym_addrs.addr_expr_eval_result, 0);
+
+      trace_debug ("lib: trace_buffer_is_full: %d, "
+		   "stopping_tracepoint: %s, "
+		   "ipa_expr_eval_result: %d, "
+		   "error_tracepoint: %s, ",
+		   ipa_trace_buffer_is_full,
+		   paddress (ipa_stopping_tracepoint),
+		   ipa_expr_eval_result,
+		   paddress (ipa_error_tracepoint));
+
+      if (debug_threads)
+	{
+	  if (ipa_trace_buffer_is_full)
+	    trace_debug ("lib stopped due to full buffer.");
+	  if (ipa_stopping_tracepoint)
+	    trace_debug ("lib stopped due to tpoint");
+	  if (ipa_error_tracepoint)
+	    trace_debug ("lib stopped due to error");
+	}
+
+      if (ipa_stopping_tracepoint != 0)
+	{
+	  stopping_tracepoint
+	    = fast_tracepoint_from_ipa_tpoint_address (ipa_stopping_tracepoint);
+	}
+      else if (ipa_expr_eval_result != expr_eval_no_error)
+	{
+	  expr_eval_result = ipa_expr_eval_result;
+	  error_tracepoint
+	    = fast_tracepoint_from_ipa_tpoint_address (ipa_error_tracepoint);
+	}
+      stop_tracing ();
+      return 1;
+    }
+  else if (stop_pc == ipa_sym_addrs.addr_flush_trace_buffer)
+    {
+      trace_debug ("lib stopped at flush_trace_buffer");
+      return 1;
+    }
+
+  return 0;
+}
+
+/* Return true if TINFO just hit a tracepoint.  Collect data if
+   so.  */
+
+int
+tracepoint_was_hit (struct thread_info *tinfo, CORE_ADDR stop_pc)
+{
+  struct tracepoint *tpoint;
+  int ret = 0;
+  struct trap_tracepoint_ctx ctx;
+
+  /* Not tracing, don't handle.  */
+  if (!tracing)
+    return 0;
+
+  ctx.base.type = trap_tracepoint;
+  ctx.regcache = get_thread_regcache (tinfo, 1);
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    {
+      /* Note that we collect fast tracepoints here as well.  We'll
+	 step over the fast tracepoint jump later, which avoids the
+	 double collect.  However, we don't collect for static
+	 tracepoints here, because UST markers are compiled in program,
+	 and probes will be executed in program.  So static tracepoints
+	 are collected there.   */
+      if (tpoint->enabled && stop_pc == tpoint->address
+	  && tpoint->type != static_tracepoint)
+	{
+	  trace_debug ("Thread %s at address of tracepoint %d at 0x%s",
+		       target_pid_to_str (tinfo->id),
+		       tpoint->number, paddress (tpoint->address));
+
+	  /* Test the condition if present, and collect if true.  */
+	  if (!tpoint->cond
+	      || (condition_true_at_tracepoint
+		  ((struct tracepoint_hit_ctx *) &ctx, tpoint)))
+	    collect_data_at_tracepoint ((struct tracepoint_hit_ctx *) &ctx,
+					stop_pc, tpoint);
+
+	  if (stopping_tracepoint
+	      || trace_buffer_is_full
+	      || expr_eval_result != expr_eval_no_error)
+	    {
+	      stop_tracing ();
+	    }
+	  /* If the tracepoint had a 'while-stepping' action, then set
+	     the thread to collect this tracepoint on the following
+	     single-steps.  */
+	  else if (tpoint->step_count > 0)
+	    {
+	      add_while_stepping_state (tinfo,
+					tpoint->number, tpoint->address);
+	    }
+
+	  ret = 1;
+	}
+    }
+
+  return ret;
+}
+
+#endif
+
+#if defined IN_PROCESS_AGENT && defined HAVE_UST
+struct ust_marker_data;
+static void collect_ust_data_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+					    struct traceframe *tframe);
+#endif
+
+/* Create a trace frame for the hit of the given tracepoint in the
+   given thread.  */
+
+static void
+collect_data_at_tracepoint (struct tracepoint_hit_ctx *ctx, CORE_ADDR stop_pc,
+			    struct tracepoint *tpoint)
+{
+  struct traceframe *tframe;
+  int acti;
+
+  /* Only count it as a hit when we actually collect data.  */
+  tpoint->hit_count++;
+
+  /* If we've exceeded a defined pass count, record the event for
+     later, and finish the collection for this hit.  This test is only
+     for nonstepping tracepoints, stepping tracepoints test at the end
+     of their while-stepping loop.  */
+  if (tpoint->pass_count > 0
+      && tpoint->hit_count >= tpoint->pass_count
+      && tpoint->step_count == 0
+      && stopping_tracepoint == NULL)
+    stopping_tracepoint = tpoint;
+
+  trace_debug ("Making new traceframe for tracepoint %d at 0x%s, hit %" PRIu64,
+	       tpoint->number, paddress (tpoint->address), tpoint->hit_count);
+
+  tframe = add_traceframe (tpoint);
+
+  if (tframe)
+    {
+      for (acti = 0; acti < tpoint->numactions; ++acti)
+	{
+#ifndef IN_PROCESS_AGENT
+	  trace_debug ("Tracepoint %d at 0x%s about to do action '%s'",
+		       tpoint->number, paddress (tpoint->address),
+		       tpoint->actions_str[acti]);
+#endif
+
+	  do_action_at_tracepoint (ctx, stop_pc, tpoint, tframe,
+				   tpoint->actions[acti]);
+	}
+
+      finish_traceframe (tframe);
+    }
+
+  if (tframe == NULL && tracing)
+    trace_buffer_is_full = 1;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+static void
+collect_data_at_step (struct tracepoint_hit_ctx *ctx,
+		      CORE_ADDR stop_pc,
+		      struct tracepoint *tpoint, int current_step)
+{
+  struct traceframe *tframe;
+  int acti;
+
+  trace_debug ("Making new step traceframe for "
+	       "tracepoint %d at 0x%s, step %d of %" PRIu64 ", hit %" PRIu64,
+	       tpoint->number, paddress (tpoint->address),
+	       current_step, tpoint->step_count,
+	       tpoint->hit_count);
+
+  tframe = add_traceframe (tpoint);
+
+  if (tframe)
+    {
+      for (acti = 0; acti < tpoint->num_step_actions; ++acti)
+	{
+	  trace_debug ("Tracepoint %d at 0x%s about to do step action '%s'",
+		       tpoint->number, paddress (tpoint->address),
+		       tpoint->step_actions_str[acti]);
+
+	  do_action_at_tracepoint (ctx, stop_pc, tpoint, tframe,
+				   tpoint->step_actions[acti]);
+	}
+
+      finish_traceframe (tframe);
+    }
+
+  if (tframe == NULL && tracing)
+    trace_buffer_is_full = 1;
+}
+
+#endif
+
+#ifdef IN_PROCESS_AGENT
+/* The target description index for IPA.  Passed from gdbserver, used
+   to select ipa_tdesc.  */
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR int ipa_tdesc_idx;
+EXTERN_C_POP
+#endif
+
+static struct regcache *
+get_context_regcache (struct tracepoint_hit_ctx *ctx)
+{
+  struct regcache *regcache = NULL;
+#ifdef IN_PROCESS_AGENT
+  const struct target_desc *ipa_tdesc = get_ipa_tdesc (ipa_tdesc_idx);
+
+  if (ctx->type == fast_tracepoint)
+    {
+      struct fast_tracepoint_ctx *fctx = (struct fast_tracepoint_ctx *) ctx;
+      if (!fctx->regcache_initted)
+	{
+	  fctx->regcache_initted = 1;
+	  init_register_cache (&fctx->regcache, ipa_tdesc, fctx->regspace);
+	  supply_regblock (&fctx->regcache, NULL);
+	  supply_fast_tracepoint_registers (&fctx->regcache, fctx->regs);
+	}
+      regcache = &fctx->regcache;
+    }
+#ifdef HAVE_UST
+  if (ctx->type == static_tracepoint)
+    {
+      struct static_tracepoint_ctx *sctx
+	= (struct static_tracepoint_ctx *) ctx;
+
+      if (!sctx->regcache_initted)
+	{
+	  sctx->regcache_initted = 1;
+	  init_register_cache (&sctx->regcache, ipa_tdesc, sctx->regspace);
+	  supply_regblock (&sctx->regcache, NULL);
+	  /* Pass down the tracepoint address, because REGS doesn't
+	     include the PC, but we know what it must have been.  */
+	  supply_static_tracepoint_registers (&sctx->regcache,
+					      (const unsigned char *)
+					      sctx->regs,
+					      sctx->tpoint->address);
+	}
+      regcache = &sctx->regcache;
+    }
+#endif
+#else
+  if (ctx->type == trap_tracepoint)
+    {
+      struct trap_tracepoint_ctx *tctx = (struct trap_tracepoint_ctx *) ctx;
+      regcache = tctx->regcache;
+    }
+#endif
+
+  gdb_assert (regcache != NULL);
+
+  return regcache;
+}
+
+static void
+do_action_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+			 CORE_ADDR stop_pc,
+			 struct tracepoint *tpoint,
+			 struct traceframe *tframe,
+			 struct tracepoint_action *taction)
+{
+  enum eval_result_type err;
+
+  switch (taction->type)
+    {
+    case 'M':
+      {
+	struct collect_memory_action *maction;
+	struct eval_agent_expr_context ax_ctx;
+
+	maction = (struct collect_memory_action *) taction;
+	ax_ctx.regcache = NULL;
+	ax_ctx.tframe = tframe;
+	ax_ctx.tpoint = tpoint;
+
+	trace_debug ("Want to collect %s bytes at 0x%s (basereg %d)",
+		     pulongest (maction->len),
+		     paddress (maction->addr), maction->basereg);
+	/* (should use basereg) */
+	agent_mem_read (&ax_ctx, NULL, (CORE_ADDR) maction->addr,
+			maction->len);
+	break;
+      }
+    case 'R':
+      {
+	unsigned char *regspace;
+	struct regcache tregcache;
+	struct regcache *context_regcache;
+	int regcache_size;
+
+	trace_debug ("Want to collect registers");
+
+	context_regcache = get_context_regcache (ctx);
+	regcache_size = register_cache_size (context_regcache->tdesc);
+
+	/* Collect all registers for now.  */
+	regspace = add_traceframe_block (tframe, tpoint, 1 + regcache_size);
+	if (regspace == NULL)
+	  {
+	    trace_debug ("Trace buffer block allocation failed, skipping");
+	    break;
+	  }
+	/* Identify a register block.  */
+	*regspace = 'R';
+
+	/* Wrap the regblock in a register cache (in the stack, we
+	   don't want to malloc here).  */
+	init_register_cache (&tregcache, context_regcache->tdesc,
+			     regspace + 1);
+
+	/* Copy the register data to the regblock.  */
+	regcache_cpy (&tregcache, context_regcache);
+
+#ifndef IN_PROCESS_AGENT
+	/* On some platforms, trap-based tracepoints will have the PC
+	   pointing to the next instruction after the trap, but we
+	   don't want the user or GDB trying to guess whether the
+	   saved PC needs adjusting; so always record the adjusted
+	   stop_pc.  Note that we can't use tpoint->address instead,
+	   since it will be wrong for while-stepping actions.  This
+	   adjustment is a nop for fast tracepoints collected from the
+	   in-process lib (but not if GDBserver is collecting one
+	   preemptively), since the PC had already been adjusted to
+	   contain the tracepoint's address by the jump pad.  */
+	trace_debug ("Storing stop pc (0x%s) in regblock",
+		     paddress (stop_pc));
+
+	/* This changes the regblock, not the thread's
+	   regcache.  */
+	regcache_write_pc (&tregcache, stop_pc);
+#endif
+      }
+      break;
+    case 'X':
+      {
+	struct eval_expr_action *eaction;
+	struct eval_agent_expr_context ax_ctx;
+
+	eaction = (struct eval_expr_action *) taction;
+	ax_ctx.regcache = get_context_regcache (ctx);
+	ax_ctx.tframe = tframe;
+	ax_ctx.tpoint = tpoint;
+
+	trace_debug ("Want to evaluate expression");
+
+	err = gdb_eval_agent_expr (&ax_ctx, eaction->expr, NULL);
+
+	if (err != expr_eval_no_error)
+	  {
+	    record_tracepoint_error (tpoint, "action expression", err);
+	    return;
+	  }
+      }
+      break;
+    case 'L':
+      {
+#if defined IN_PROCESS_AGENT && defined HAVE_UST
+	trace_debug ("Want to collect static trace data");
+	collect_ust_data_at_tracepoint (ctx, tframe);
+#else
+	trace_debug ("warning: collecting static trace data, "
+		     "but static tracepoints are not supported");
+#endif
+      }
+      break;
+    default:
+      trace_debug ("unknown trace action '%c', ignoring", taction->type);
+      break;
+    }
+}
+
+static int
+condition_true_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+			      struct tracepoint *tpoint)
+{
+  ULONGEST value = 0;
+  enum eval_result_type err;
+
+  /* Presently, gdbserver doesn't run compiled conditions, only the
+     IPA does.  If the program stops at a fast tracepoint's address
+     (e.g., due to a breakpoint, trap tracepoint, or stepping),
+     gdbserver preemptively collect the fast tracepoint.  Later, on
+     resume, gdbserver steps over the fast tracepoint like it steps
+     over breakpoints, so that the IPA doesn't see that fast
+     tracepoint.  This avoids double collects of fast tracepoints in
+     that stopping scenario.  Having gdbserver itself handle the fast
+     tracepoint gives the user a consistent view of when fast or trap
+     tracepoints are collected, compared to an alternative where only
+     trap tracepoints are collected on stop, and fast tracepoints on
+     resume.  When a fast tracepoint is being processed by gdbserver,
+     it is always the non-compiled condition expression that is
+     used.  */
+#ifdef IN_PROCESS_AGENT
+  if (tpoint->compiled_cond)
+    {
+      struct fast_tracepoint_ctx *fctx = (struct fast_tracepoint_ctx *) ctx;
+      err = ((condfn) (uintptr_t) (tpoint->compiled_cond)) (fctx->regs, &value);
+    }
+  else
+#endif
+    {
+      struct eval_agent_expr_context ax_ctx;
+
+      ax_ctx.regcache = get_context_regcache (ctx);
+      ax_ctx.tframe = NULL;
+      ax_ctx.tpoint = tpoint;
+
+      err = gdb_eval_agent_expr (&ax_ctx, tpoint->cond, &value);
+    }
+  if (err != expr_eval_no_error)
+    {
+      record_tracepoint_error (tpoint, "condition", err);
+      /* The error case must return false.  */
+      return 0;
+    }
+
+  trace_debug ("Tracepoint %d at 0x%s condition evals to %s",
+	       tpoint->number, paddress (tpoint->address),
+	       pulongest (value));
+  return (value ? 1 : 0);
+}
+
+/* Do memory copies for bytecodes.  */
+/* Do the recording of memory blocks for actions and bytecodes.  */
+
+int
+agent_mem_read (struct eval_agent_expr_context *ctx,
+		unsigned char *to, CORE_ADDR from, ULONGEST len)
+{
+  unsigned char *mspace;
+  ULONGEST remaining = len;
+  unsigned short blocklen;
+
+  /* If a 'to' buffer is specified, use it.  */
+  if (to != NULL)
+    {
+      read_inferior_memory (from, to, len);
+      return 0;
+    }
+
+  /* Otherwise, create a new memory block in the trace buffer.  */
+  while (remaining > 0)
+    {
+      size_t sp;
+
+      blocklen = (remaining > 65535 ? 65535 : remaining);
+      sp = 1 + sizeof (from) + sizeof (blocklen) + blocklen;
+      mspace = add_traceframe_block (ctx->tframe, ctx->tpoint, sp);
+      if (mspace == NULL)
+	return 1;
+      /* Identify block as a memory block.  */
+      *mspace = 'M';
+      ++mspace;
+      /* Record address and size.  */
+      memcpy (mspace, &from, sizeof (from));
+      mspace += sizeof (from);
+      memcpy (mspace, &blocklen, sizeof (blocklen));
+      mspace += sizeof (blocklen);
+      /* Record the memory block proper.  */
+      read_inferior_memory (from, mspace, blocklen);
+      trace_debug ("%d bytes recorded", blocklen);
+      remaining -= blocklen;
+      from += blocklen;
+    }
+  return 0;
+}
+
+int
+agent_mem_read_string (struct eval_agent_expr_context *ctx,
+		       unsigned char *to, CORE_ADDR from, ULONGEST len)
+{
+  unsigned char *buf, *mspace;
+  ULONGEST remaining = len;
+  unsigned short blocklen, i;
+
+  /* To save a bit of space, block lengths are 16-bit, so break large
+     requests into multiple blocks.  Bordering on overkill for strings,
+     but it could happen that someone specifies a large max length.  */
+  while (remaining > 0)
+    {
+      size_t sp;
+
+      blocklen = (remaining > 65535 ? 65535 : remaining);
+      /* We want working space to accumulate nonzero bytes, since
+	 traceframes must have a predecided size (otherwise it gets
+	 harder to wrap correctly for the circular case, etc).  */
+      buf = (unsigned char *) xmalloc (blocklen + 1);
+      for (i = 0; i < blocklen; ++i)
+	{
+	  /* Read the string one byte at a time, in case the string is
+	     at the end of a valid memory area - we don't want a
+	     correctly-terminated string to engender segvio
+	     complaints.  */
+	  read_inferior_memory (from + i, buf + i, 1);
+
+	  if (buf[i] == '\0')
+	    {
+	      blocklen = i + 1;
+	      /* Make sure outer loop stops now too.  */
+	      remaining = blocklen;
+	      break;
+	    }
+	}
+      sp = 1 + sizeof (from) + sizeof (blocklen) + blocklen;
+      mspace = add_traceframe_block (ctx->tframe, ctx->tpoint, sp);
+      if (mspace == NULL)
+	{
+	  xfree (buf);
+	  return 1;
+	}
+      /* Identify block as a memory block.  */
+      *mspace = 'M';
+      ++mspace;
+      /* Record address and size.  */
+      memcpy ((void *) mspace, (void *) &from, sizeof (from));
+      mspace += sizeof (from);
+      memcpy ((void *) mspace, (void *) &blocklen, sizeof (blocklen));
+      mspace += sizeof (blocklen);
+      /* Copy the string contents.  */
+      memcpy ((void *) mspace, (void *) buf, blocklen);
+      remaining -= blocklen;
+      from += blocklen;
+      xfree (buf);
+    }
+  return 0;
+}
+
+/* Record the value of a trace state variable.  */
+
+int
+agent_tsv_read (struct eval_agent_expr_context *ctx, int n)
+{
+  unsigned char *vspace;
+  LONGEST val;
+
+  vspace = add_traceframe_block (ctx->tframe, ctx->tpoint,
+				 1 + sizeof (n) + sizeof (LONGEST));
+  if (vspace == NULL)
+    return 1;
+  /* Identify block as a variable.  */
+  *vspace = 'V';
+  /* Record variable's number and value.  */
+  memcpy (vspace + 1, &n, sizeof (n));
+  val = get_trace_state_variable_value (n);
+  memcpy (vspace + 1 + sizeof (n), &val, sizeof (val));
+  trace_debug ("Variable %d recorded", n);
+  return 0;
+}
+
+#ifndef IN_PROCESS_AGENT
+
+/* Callback for traceframe_walk_blocks, used to find a given block
+   type in a traceframe.  */
+
+static int
+match_blocktype (char blocktype, unsigned char *dataptr, void *data)
+{
+  char *wantedp = (char *) data;
+
+  if (*wantedp == blocktype)
+    return 1;
+
+  return 0;
+}
+
+/* Walk over all traceframe blocks of the traceframe buffer starting
+   at DATABASE, of DATASIZE bytes long, and call CALLBACK for each
+   block found, passing in DATA unmodified.  If CALLBACK returns true,
+   this returns a pointer to where the block is found.  Returns NULL
+   if no callback call returned true, indicating that all blocks have
+   been walked.  */
+
+static unsigned char *
+traceframe_walk_blocks (unsigned char *database, unsigned int datasize,
+			int tfnum,
+			int (*callback) (char blocktype,
+					 unsigned char *dataptr,
+					 void *data),
+			void *data)
+{
+  unsigned char *dataptr;
+
+  if (datasize == 0)
+    {
+      trace_debug ("traceframe %d has no data", tfnum);
+      return NULL;
+    }
+
+  /* Iterate through a traceframe's blocks, looking for a block of the
+     requested type.  */
+  for (dataptr = database;
+       dataptr < database + datasize;
+       /* nothing */)
+    {
+      char blocktype;
+      unsigned short mlen;
+
+      if (dataptr == trace_buffer_wrap)
+	{
+	  /* Adjust to reflect wrapping part of the frame around to
+	     the beginning.  */
+	  datasize = dataptr - database;
+	  dataptr = database = trace_buffer_lo;
+	}
+
+      blocktype = *dataptr++;
+
+      if ((*callback) (blocktype, dataptr, data))
+	return dataptr;
+
+      switch (blocktype)
+	{
+	case 'R':
+	  /* Skip over the registers block.  */
+	  dataptr += current_target_desc ()->registers_size;
+	  break;
+	case 'M':
+	  /* Skip over the memory block.  */
+	  dataptr += sizeof (CORE_ADDR);
+	  memcpy (&mlen, dataptr, sizeof (mlen));
+	  dataptr += (sizeof (mlen) + mlen);
+	  break;
+	case 'V':
+	  /* Skip over the TSV block.  */
+	  dataptr += (sizeof (int) + sizeof (LONGEST));
+	  break;
+	case 'S':
+	  /* Skip over the static trace data block.  */
+	  memcpy (&mlen, dataptr, sizeof (mlen));
+	  dataptr += (sizeof (mlen) + mlen);
+	  break;
+	default:
+	  trace_debug ("traceframe %d has unknown block type 0x%x",
+		       tfnum, blocktype);
+	  return NULL;
+	}
+    }
+
+  return NULL;
+}
+
+/* Look for the block of type TYPE_WANTED in the traceframe starting
+   at DATABASE of DATASIZE bytes long.  TFNUM is the traceframe
+   number.  */
+
+static unsigned char *
+traceframe_find_block_type (unsigned char *database, unsigned int datasize,
+			    int tfnum, char type_wanted)
+{
+  return traceframe_walk_blocks (database, datasize, tfnum,
+				 match_blocktype, &type_wanted);
+}
+
+static unsigned char *
+traceframe_find_regblock (struct traceframe *tframe, int tfnum)
+{
+  unsigned char *regblock;
+
+  regblock = traceframe_find_block_type (tframe->data,
+					 tframe->data_size,
+					 tfnum, 'R');
+
+  if (regblock == NULL)
+    trace_debug ("traceframe %d has no register data", tfnum);
+
+  return regblock;
+}
+
+/* Get registers from a traceframe.  */
+
+int
+fetch_traceframe_registers (int tfnum, struct regcache *regcache, int regnum)
+{
+  unsigned char *dataptr;
+  struct tracepoint *tpoint;
+  struct traceframe *tframe;
+
+  tframe = find_traceframe (tfnum);
+
+  if (tframe == NULL)
+    {
+      trace_debug ("traceframe %d not found", tfnum);
+      return 1;
+    }
+
+  dataptr = traceframe_find_regblock (tframe, tfnum);
+  if (dataptr == NULL)
+    {
+      /* Mark registers unavailable.  */
+      supply_regblock (regcache, NULL);
+
+      /* We can generally guess at a PC, although this will be
+	 misleading for while-stepping frames and multi-location
+	 tracepoints.  */
+      tpoint = find_next_tracepoint_by_number (NULL, tframe->tpnum);
+      if (tpoint != NULL)
+	regcache_write_pc (regcache, tpoint->address);
+    }
+  else
+    supply_regblock (regcache, dataptr);
+
+  return 0;
+}
+
+static CORE_ADDR
+traceframe_get_pc (struct traceframe *tframe)
+{
+  struct regcache regcache;
+  unsigned char *dataptr;
+  const struct target_desc *tdesc = current_target_desc ();
+
+  dataptr = traceframe_find_regblock (tframe, -1);
+  if (dataptr == NULL)
+    return 0;
+
+  init_register_cache (&regcache, tdesc, dataptr);
+  return regcache_read_pc (&regcache);
+}
+
+/* Read a requested block of memory from a trace frame.  */
+
+int
+traceframe_read_mem (int tfnum, CORE_ADDR addr,
+		     unsigned char *buf, ULONGEST length,
+		     ULONGEST *nbytes)
+{
+  struct traceframe *tframe;
+  unsigned char *database, *dataptr;
+  unsigned int datasize;
+  CORE_ADDR maddr;
+  unsigned short mlen;
+
+  trace_debug ("traceframe_read_mem");
+
+  tframe = find_traceframe (tfnum);
+
+  if (!tframe)
+    {
+      trace_debug ("traceframe %d not found", tfnum);
+      return 1;
+    }
+
+  datasize = tframe->data_size;
+  database = dataptr = &tframe->data[0];
+
+  /* Iterate through a traceframe's blocks, looking for memory.  */
+  while ((dataptr = traceframe_find_block_type (dataptr,
+						datasize
+						- (dataptr - database),
+						tfnum, 'M')) != NULL)
+    {
+      memcpy (&maddr, dataptr, sizeof (maddr));
+      dataptr += sizeof (maddr);
+      memcpy (&mlen, dataptr, sizeof (mlen));
+      dataptr += sizeof (mlen);
+      trace_debug ("traceframe %d has %d bytes at %s",
+		   tfnum, mlen, paddress (maddr));
+
+      /* If the block includes the first part of the desired range,
+	 return as much it has; GDB will re-request the remainder,
+	 which might be in a different block of this trace frame.  */
+      if (maddr <= addr && addr < (maddr + mlen))
+	{
+	  ULONGEST amt = (maddr + mlen) - addr;
+	  if (amt > length)
+	    amt = length;
+
+	  memcpy (buf, dataptr + (addr - maddr), amt);
+	  *nbytes = amt;
+	  return 0;
+	}
+
+      /* Skip over this block.  */
+      dataptr += mlen;
+    }
+
+  trace_debug ("traceframe %d has no memory data for the desired region",
+	       tfnum);
+
+  *nbytes = 0;
+  return 0;
+}
+
+static int
+traceframe_read_tsv (int tsvnum, LONGEST *val)
+{
+  client_state &cs = get_client_state ();
+  int tfnum;
+  struct traceframe *tframe;
+  unsigned char *database, *dataptr;
+  unsigned int datasize;
+  int vnum;
+  int found = 0;
+
+  trace_debug ("traceframe_read_tsv");
+
+  tfnum = cs.current_traceframe;
+
+  if (tfnum < 0)
+    {
+      trace_debug ("no current traceframe");
+      return 1;
+    }
+
+  tframe = find_traceframe (tfnum);
+
+  if (tframe == NULL)
+    {
+      trace_debug ("traceframe %d not found", tfnum);
+      return 1;
+    }
+
+  datasize = tframe->data_size;
+  database = dataptr = &tframe->data[0];
+
+  /* Iterate through a traceframe's blocks, looking for the last
+     matched tsv.  */
+  while ((dataptr = traceframe_find_block_type (dataptr,
+						datasize
+						- (dataptr - database),
+						tfnum, 'V')) != NULL)
+    {
+      memcpy (&vnum, dataptr, sizeof (vnum));
+      dataptr += sizeof (vnum);
+
+      trace_debug ("traceframe %d has variable %d", tfnum, vnum);
+
+      /* Check that this is the variable we want.  */
+      if (tsvnum == vnum)
+	{
+	  memcpy (val, dataptr, sizeof (*val));
+	  found = 1;
+	}
+
+      /* Skip over this block.  */
+      dataptr += sizeof (LONGEST);
+    }
+
+  if (!found)
+    trace_debug ("traceframe %d has no data for variable %d",
+		 tfnum, tsvnum);
+  return !found;
+}
+
+/* Read a requested block of static tracepoint data from a trace
+   frame.  */
+
+int
+traceframe_read_sdata (int tfnum, ULONGEST offset,
+		       unsigned char *buf, ULONGEST length,
+		       ULONGEST *nbytes)
+{
+  struct traceframe *tframe;
+  unsigned char *database, *dataptr;
+  unsigned int datasize;
+  unsigned short mlen;
+
+  trace_debug ("traceframe_read_sdata");
+
+  tframe = find_traceframe (tfnum);
+
+  if (!tframe)
+    {
+      trace_debug ("traceframe %d not found", tfnum);
+      return 1;
+    }
+
+  datasize = tframe->data_size;
+  database = &tframe->data[0];
+
+  /* Iterate through a traceframe's blocks, looking for static
+     tracepoint data.  */
+  dataptr = traceframe_find_block_type (database, datasize,
+					tfnum, 'S');
+  if (dataptr != NULL)
+    {
+      memcpy (&mlen, dataptr, sizeof (mlen));
+      dataptr += sizeof (mlen);
+      if (offset < mlen)
+	{
+	  if (offset + length > mlen)
+	    length = mlen - offset;
+
+	  memcpy (buf, dataptr, length);
+	  *nbytes = length;
+	}
+      else
+	*nbytes = 0;
+      return 0;
+    }
+
+  trace_debug ("traceframe %d has no static trace data", tfnum);
+
+  *nbytes = 0;
+  return 0;
+}
+
+/* Callback for traceframe_walk_blocks.  Builds a traceframe-info
+   object.  DATA is pointer to a struct buffer holding the
+   traceframe-info object being built.  */
+
+static int
+build_traceframe_info_xml (char blocktype, unsigned char *dataptr, void *data)
+{
+  struct buffer *buffer = (struct buffer *) data;
+
+  switch (blocktype)
+    {
+    case 'M':
+      {
+	unsigned short mlen;
+	CORE_ADDR maddr;
+
+	memcpy (&maddr, dataptr, sizeof (maddr));
+	dataptr += sizeof (maddr);
+	memcpy (&mlen, dataptr, sizeof (mlen));
+	dataptr += sizeof (mlen);
+	buffer_xml_printf (buffer,
+			   "<memory start=\"0x%s\" length=\"0x%s\"/>\n",
+			   paddress (maddr), phex_nz (mlen, sizeof (mlen)));
+	break;
+      }
+    case 'V':
+      {
+	int vnum;
+
+	memcpy (&vnum, dataptr, sizeof (vnum));
+	buffer_xml_printf (buffer, "<tvar id=\"%d\"/>\n", vnum);
+	break;
+      }
+    case 'R':
+    case 'S':
+      {
+	break;
+      }
+    default:
+      warning ("Unhandled trace block type (%d) '%c ' "
+	       "while building trace frame info.",
+	       blocktype, blocktype);
+      break;
+    }
+
+  return 0;
+}
+
+/* Build a traceframe-info object for traceframe number TFNUM into
+   BUFFER.  */
+
+int
+traceframe_read_info (int tfnum, struct buffer *buffer)
+{
+  struct traceframe *tframe;
+
+  trace_debug ("traceframe_read_info");
+
+  tframe = find_traceframe (tfnum);
+
+  if (!tframe)
+    {
+      trace_debug ("traceframe %d not found", tfnum);
+      return 1;
+    }
+
+  buffer_grow_str (buffer, "<traceframe-info>\n");
+  traceframe_walk_blocks (tframe->data, tframe->data_size,
+			  tfnum, build_traceframe_info_xml, buffer);
+  buffer_grow_str0 (buffer, "</traceframe-info>\n");
+  return 0;
+}
+
+/* Return the first fast tracepoint whose jump pad contains PC.  */
+
+static struct tracepoint *
+fast_tracepoint_from_jump_pad_address (CORE_ADDR pc)
+{
+  struct tracepoint *tpoint;
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    if (tpoint->type == fast_tracepoint)
+      if (tpoint->jump_pad <= pc && pc < tpoint->jump_pad_end)
+	return tpoint;
+
+  return NULL;
+}
+
+/* Return the first fast tracepoint whose trampoline contains PC.  */
+
+static struct tracepoint *
+fast_tracepoint_from_trampoline_address (CORE_ADDR pc)
+{
+  struct tracepoint *tpoint;
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    {
+      if (tpoint->type == fast_tracepoint
+	  && tpoint->trampoline <= pc && pc < tpoint->trampoline_end)
+	return tpoint;
+    }
+
+  return NULL;
+}
+
+/* Return GDBserver's tracepoint that matches the IP Agent's
+   tracepoint object that lives at IPA_TPOINT_OBJ in the IP Agent's
+   address space.  */
+
+static struct tracepoint *
+fast_tracepoint_from_ipa_tpoint_address (CORE_ADDR ipa_tpoint_obj)
+{
+  struct tracepoint *tpoint;
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    if (tpoint->type == fast_tracepoint)
+      if (tpoint->obj_addr_on_target == ipa_tpoint_obj)
+	return tpoint;
+
+  return NULL;
+}
+
+#endif
+
+/* The type of the object that is used to synchronize fast tracepoint
+   collection.  */
+
+typedef struct collecting_t
+{
+  /* The fast tracepoint number currently collecting.  */
+  uintptr_t tpoint;
+
+  /* A number that GDBserver can use to identify the thread that is
+     presently holding the collect lock.  This need not (and usually
+     is not) the thread id, as getting the current thread ID usually
+     requires a system call, which we want to avoid like the plague.
+     Usually this is thread's TCB, found in the TLS (pseudo-)
+     register, which is readable with a single insn on several
+     architectures.  */
+  uintptr_t thread_area;
+} collecting_t;
+
+#ifndef IN_PROCESS_AGENT
+
+void
+force_unlock_trace_buffer (void)
+{
+  write_inferior_data_pointer (ipa_sym_addrs.addr_collecting, 0);
+}
+
+/* Check if the thread identified by THREAD_AREA which is stopped at
+   STOP_PC, is presently locking the fast tracepoint collection, and
+   if so, gather some status of said collection.  Returns 0 if the
+   thread isn't collecting or in the jump pad at all.  1, if in the
+   jump pad (or within gdb_collect) and hasn't executed the adjusted
+   original insn yet (can set a breakpoint there and run to it).  2,
+   if presently executing the adjusted original insn --- in which
+   case, if we want to move the thread out of the jump pad, we need to
+   single-step it until this function returns 0.  */
+
+fast_tpoint_collect_result
+fast_tracepoint_collecting (CORE_ADDR thread_area,
+			    CORE_ADDR stop_pc,
+			    struct fast_tpoint_collect_status *status)
+{
+  CORE_ADDR ipa_collecting;
+  CORE_ADDR ipa_gdb_jump_pad_buffer, ipa_gdb_jump_pad_buffer_end;
+  CORE_ADDR ipa_gdb_trampoline_buffer;
+  CORE_ADDR ipa_gdb_trampoline_buffer_end;
+  struct tracepoint *tpoint;
+  int needs_breakpoint;
+
+  /* The thread THREAD_AREA is either:
+
+      0. not collecting at all, not within the jump pad, or within
+	 gdb_collect or one of its callees.
+
+      1. in the jump pad and haven't reached gdb_collect
+
+      2. within gdb_collect (out of the jump pad) (collect is set)
+
+      3. we're in the jump pad, after gdb_collect having returned,
+	 possibly executing the adjusted insns.
+
+      For cases 1 and 3, `collecting' may or not be set.  The jump pad
+      doesn't have any complicated jump logic, so we can tell if the
+      thread is executing the adjust original insn or not by just
+      matching STOP_PC with known jump pad addresses.  If we it isn't
+      yet executing the original insn, set a breakpoint there, and let
+      the thread run to it, so to quickly step over a possible (many
+      insns) gdb_collect call.  Otherwise, or when the breakpoint is
+      hit, only a few (small number of) insns are left to be executed
+      in the jump pad.  Single-step the thread until it leaves the
+      jump pad.  */
+
+ again:
+  tpoint = NULL;
+  needs_breakpoint = 0;
+  trace_debug ("fast_tracepoint_collecting");
+
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_jump_pad_buffer,
+				  &ipa_gdb_jump_pad_buffer))
+    {
+      internal_error (__FILE__, __LINE__,
+		      "error extracting `gdb_jump_pad_buffer'");
+    }
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_jump_pad_buffer_end,
+				  &ipa_gdb_jump_pad_buffer_end))
+    {
+      internal_error (__FILE__, __LINE__,
+		      "error extracting `gdb_jump_pad_buffer_end'");
+    }
+
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer,
+				  &ipa_gdb_trampoline_buffer))
+    {
+      internal_error (__FILE__, __LINE__,
+		      "error extracting `gdb_trampoline_buffer'");
+    }
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_trampoline_buffer_end,
+				  &ipa_gdb_trampoline_buffer_end))
+    {
+      internal_error (__FILE__, __LINE__,
+		      "error extracting `gdb_trampoline_buffer_end'");
+    }
+
+  if (ipa_gdb_jump_pad_buffer <= stop_pc
+      && stop_pc < ipa_gdb_jump_pad_buffer_end)
+    {
+      /* We can tell which tracepoint(s) the thread is collecting by
+	 matching the jump pad address back to the tracepoint.  */
+      tpoint = fast_tracepoint_from_jump_pad_address (stop_pc);
+      if (tpoint == NULL)
+	{
+	  warning ("in jump pad, but no matching tpoint?");
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+      else
+	{
+	  trace_debug ("in jump pad of tpoint (%d, %s); jump_pad(%s, %s); "
+		       "adj_insn(%s, %s)",
+		       tpoint->number, paddress (tpoint->address),
+		       paddress (tpoint->jump_pad),
+		       paddress (tpoint->jump_pad_end),
+		       paddress (tpoint->adjusted_insn_addr),
+		       paddress (tpoint->adjusted_insn_addr_end));
+	}
+
+      /* Definitely in the jump pad.  May or may not need
+	 fast-exit-jump-pad breakpoint.  */
+      if (tpoint->jump_pad <= stop_pc
+	  && stop_pc < tpoint->adjusted_insn_addr)
+	needs_breakpoint =  1;
+    }
+  else if (ipa_gdb_trampoline_buffer <= stop_pc
+	   && stop_pc < ipa_gdb_trampoline_buffer_end)
+    {
+      /* We can tell which tracepoint(s) the thread is collecting by
+	 matching the trampoline address back to the tracepoint.  */
+      tpoint = fast_tracepoint_from_trampoline_address (stop_pc);
+      if (tpoint == NULL)
+	{
+	  warning ("in trampoline, but no matching tpoint?");
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+      else
+	{
+	  trace_debug ("in trampoline of tpoint (%d, %s); trampoline(%s, %s)",
+		       tpoint->number, paddress (tpoint->address),
+		       paddress (tpoint->trampoline),
+		       paddress (tpoint->trampoline_end));
+	}
+
+      /* Have not reached jump pad yet, but treat the trampoline as a
+	 part of the jump pad that is before the adjusted original
+	 instruction.  */
+      needs_breakpoint = 1;
+    }
+  else
+    {
+      collecting_t ipa_collecting_obj;
+
+      /* If `collecting' is set/locked, then the THREAD_AREA thread
+	 may or not be the one holding the lock.  We have to read the
+	 lock to find out.  */
+
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_collecting,
+				      &ipa_collecting))
+	{
+	  trace_debug ("fast_tracepoint_collecting:"
+		       " failed reading 'collecting' in the inferior");
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+
+      if (!ipa_collecting)
+	{
+	  trace_debug ("fast_tracepoint_collecting: not collecting"
+		       " (and nobody is).");
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+
+      /* Some thread is collecting.  Check which.  */
+      if (read_inferior_memory (ipa_collecting,
+				(unsigned char *) &ipa_collecting_obj,
+				sizeof (ipa_collecting_obj)) != 0)
+	goto again;
+
+      if (ipa_collecting_obj.thread_area != thread_area)
+	{
+	  trace_debug ("fast_tracepoint_collecting: not collecting "
+		       "(another thread is)");
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+
+      tpoint
+	= fast_tracepoint_from_ipa_tpoint_address (ipa_collecting_obj.tpoint);
+      if (tpoint == NULL)
+	{
+	  warning ("fast_tracepoint_collecting: collecting, "
+		   "but tpoint %s not found?",
+		   paddress ((CORE_ADDR) ipa_collecting_obj.tpoint));
+	  return fast_tpoint_collect_result::not_collecting;
+	}
+
+      /* The thread is within `gdb_collect', skip over the rest of
+	 fast tracepoint collection quickly using a breakpoint.  */
+      needs_breakpoint = 1;
+    }
+
+  /* The caller wants a bit of status detail.  */
+  if (status != NULL)
+    {
+      status->tpoint_num = tpoint->number;
+      status->tpoint_addr = tpoint->address;
+      status->adjusted_insn_addr = tpoint->adjusted_insn_addr;
+      status->adjusted_insn_addr_end = tpoint->adjusted_insn_addr_end;
+    }
+
+  if (needs_breakpoint)
+    {
+      /* Hasn't executed the original instruction yet.  Set breakpoint
+	 there, and wait till it's hit, then single-step until exiting
+	 the jump pad.  */
+
+      trace_debug ("\
+fast_tracepoint_collecting, returning continue-until-break at %s",
+		   paddress (tpoint->adjusted_insn_addr));
+
+      return fast_tpoint_collect_result::before_insn; /* continue */
+    }
+  else
+    {
+      /* Just single-step until exiting the jump pad.  */
+
+      trace_debug ("fast_tracepoint_collecting, returning "
+		   "need-single-step (%s-%s)",
+		   paddress (tpoint->adjusted_insn_addr),
+		   paddress (tpoint->adjusted_insn_addr_end));
+
+      return fast_tpoint_collect_result::at_insn; /* single-step */
+    }
+}
+
+#endif
+
+#ifdef IN_PROCESS_AGENT
+
+/* The global fast tracepoint collect lock.  Points to a collecting_t
+   object built on the stack by the jump pad, if presently locked;
+   NULL if it isn't locked.  Note that this lock *must* be set while
+   executing any *function other than the jump pad.  See
+   fast_tracepoint_collecting.  */
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR collecting_t *collecting;
+EXTERN_C_POP
+
+/* This is needed for -Wmissing-declarations.  */
+IP_AGENT_EXPORT_FUNC void gdb_collect (struct tracepoint *tpoint,
+				       unsigned char *regs);
+
+/* This routine, called from the jump pad (in asm) is designed to be
+   called from the jump pads of fast tracepoints, thus it is on the
+   critical path.  */
+
+IP_AGENT_EXPORT_FUNC void
+gdb_collect (struct tracepoint *tpoint, unsigned char *regs)
+{
+  struct fast_tracepoint_ctx ctx;
+  const struct target_desc *ipa_tdesc;
+
+  /* Don't do anything until the trace run is completely set up.  */
+  if (!tracing)
+    return;
+
+  ipa_tdesc = get_ipa_tdesc (ipa_tdesc_idx);
+  ctx.base.type = fast_tracepoint;
+  ctx.regs = regs;
+  ctx.regcache_initted = 0;
+  /* Wrap the regblock in a register cache (in the stack, we don't
+     want to malloc here).  */
+  ctx.regspace = (unsigned char *) alloca (ipa_tdesc->registers_size);
+  if (ctx.regspace == NULL)
+    {
+      trace_debug ("Trace buffer block allocation failed, skipping");
+      return;
+    }
+
+  for (ctx.tpoint = tpoint;
+       ctx.tpoint != NULL && ctx.tpoint->address == tpoint->address;
+       ctx.tpoint = ctx.tpoint->next)
+    {
+      if (!ctx.tpoint->enabled)
+	continue;
+
+      /* Multiple tracepoints of different types, such as fast tracepoint and
+	 static tracepoint, can be set at the same address.  */
+      if (ctx.tpoint->type != tpoint->type)
+	continue;
+
+      /* Test the condition if present, and collect if true.  */
+      if (ctx.tpoint->cond == NULL
+	  || condition_true_at_tracepoint ((struct tracepoint_hit_ctx *) &ctx,
+					   ctx.tpoint))
+	{
+	  collect_data_at_tracepoint ((struct tracepoint_hit_ctx *) &ctx,
+				      ctx.tpoint->address, ctx.tpoint);
+
+	  /* Note that this will cause original insns to be written back
+	     to where we jumped from, but that's OK because we're jumping
+	     back to the next whole instruction.  This will go badly if
+	     instruction restoration is not atomic though.  */
+	  if (stopping_tracepoint
+	      || trace_buffer_is_full
+	      || expr_eval_result != expr_eval_no_error)
+	    {
+	      stop_tracing ();
+	      break;
+	    }
+	}
+      else
+	{
+	  /* If there was a condition and it evaluated to false, the only
+	     way we would stop tracing is if there was an error during
+	     condition expression evaluation.  */
+	  if (expr_eval_result != expr_eval_no_error)
+	    {
+	      stop_tracing ();
+	      break;
+	    }
+	}
+    }
+}
+
+/* These global variables points to the corresponding functions.  This is
+   necessary on powerpc64, where asking for function symbol address from gdb
+   results in returning the actual code pointer, instead of the descriptor
+   pointer.  */
+
+typedef void (*gdb_collect_ptr_type) (struct tracepoint *, unsigned char *);
+typedef ULONGEST (*get_raw_reg_ptr_type) (const unsigned char *, int);
+typedef LONGEST (*get_trace_state_variable_value_ptr_type) (int);
+typedef void (*set_trace_state_variable_value_ptr_type) (int, LONGEST);
+
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR gdb_collect_ptr_type gdb_collect_ptr = gdb_collect;
+IP_AGENT_EXPORT_VAR get_raw_reg_ptr_type get_raw_reg_ptr = get_raw_reg;
+IP_AGENT_EXPORT_VAR get_trace_state_variable_value_ptr_type
+  get_trace_state_variable_value_ptr = get_trace_state_variable_value;
+IP_AGENT_EXPORT_VAR set_trace_state_variable_value_ptr_type
+  set_trace_state_variable_value_ptr = set_trace_state_variable_value;
+EXTERN_C_POP
+
+#endif
+
+#ifndef IN_PROCESS_AGENT
+
+CORE_ADDR
+get_raw_reg_func_addr (void)
+{
+  CORE_ADDR res;
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_get_raw_reg_ptr, &res))
+    {
+      error ("error extracting get_raw_reg_ptr");
+      return 0;
+    }
+  return res;
+}
+
+CORE_ADDR
+get_get_tsv_func_addr (void)
+{
+  CORE_ADDR res;
+  if (read_inferior_data_pointer (
+	ipa_sym_addrs.addr_get_trace_state_variable_value_ptr, &res))
+    {
+      error ("error extracting get_trace_state_variable_value_ptr");
+      return 0;
+    }
+  return res;
+}
+
+CORE_ADDR
+get_set_tsv_func_addr (void)
+{
+  CORE_ADDR res;
+  if (read_inferior_data_pointer (
+	ipa_sym_addrs.addr_set_trace_state_variable_value_ptr, &res))
+    {
+      error ("error extracting set_trace_state_variable_value_ptr");
+      return 0;
+    }
+  return res;
+}
+
+static void
+compile_tracepoint_condition (struct tracepoint *tpoint,
+			      CORE_ADDR *jump_entry)
+{
+  CORE_ADDR entry_point = *jump_entry;
+  enum eval_result_type err;
+
+  trace_debug ("Starting condition compilation for tracepoint %d\n",
+	       tpoint->number);
+
+  /* Initialize the global pointer to the code being built.  */
+  current_insn_ptr = *jump_entry;
+
+  emit_prologue ();
+
+  err = compile_bytecodes (tpoint->cond);
+
+  if (err == expr_eval_no_error)
+    {
+      emit_epilogue ();
+
+      /* Record the beginning of the compiled code.  */
+      tpoint->compiled_cond = entry_point;
+
+      trace_debug ("Condition compilation for tracepoint %d complete\n",
+		   tpoint->number);
+    }
+  else
+    {
+      /* Leave the unfinished code in situ, but don't point to it.  */
+
+      tpoint->compiled_cond = 0;
+
+      trace_debug ("Condition compilation for tracepoint %d failed, "
+		   "error code %d",
+		   tpoint->number, err);
+    }
+
+  /* Update the code pointer passed in.  Note that we do this even if
+     the compile fails, so that we can look at the partial results
+     instead of letting them be overwritten.  */
+  *jump_entry = current_insn_ptr;
+
+  /* Leave a gap, to aid dump decipherment.  */
+  *jump_entry += 16;
+}
+
+/* The base pointer of the IPA's heap.  This is the only memory the
+   IPA is allowed to use.  The IPA should _not_ call the inferior's
+   `malloc' during operation.  That'd be slow, and, most importantly,
+   it may not be safe.  We may be collecting a tracepoint in a signal
+   handler, for example.  */
+static CORE_ADDR target_tp_heap;
+
+/* Allocate at least SIZE bytes of memory from the IPA heap, aligned
+   to 8 bytes.  */
+
+static CORE_ADDR
+target_malloc (ULONGEST size)
+{
+  CORE_ADDR ptr;
+
+  if (target_tp_heap == 0)
+    {
+      /* We have the pointer *address*, need what it points to.  */
+      if (read_inferior_data_pointer (ipa_sym_addrs.addr_gdb_tp_heap_buffer,
+				      &target_tp_heap))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "couldn't get target heap head pointer");
+	}
+    }
+
+  ptr = target_tp_heap;
+  target_tp_heap += size;
+
+  /* Pad to 8-byte alignment.  */
+  target_tp_heap = ((target_tp_heap + 7) & ~0x7);
+
+  return ptr;
+}
+
+static CORE_ADDR
+download_agent_expr (struct agent_expr *expr)
+{
+  CORE_ADDR expr_addr;
+  CORE_ADDR expr_bytes;
+
+  expr_addr = target_malloc (sizeof (*expr));
+  target_write_memory (expr_addr, (unsigned char *) expr, sizeof (*expr));
+
+  expr_bytes = target_malloc (expr->length);
+  write_inferior_data_pointer (expr_addr + offsetof (struct agent_expr, bytes),
+			       expr_bytes);
+  target_write_memory (expr_bytes, expr->bytes, expr->length);
+
+  return expr_addr;
+}
+
+/* Align V up to N bits.  */
+#define UALIGN(V, N) (((V) + ((N) - 1)) & ~((N) - 1))
+
+/* Sync tracepoint with IPA, but leave maintenance of linked list to caller.  */
+
+static void
+download_tracepoint_1 (struct tracepoint *tpoint)
+{
+  struct tracepoint target_tracepoint;
+  CORE_ADDR tpptr = 0;
+
+  gdb_assert (tpoint->type == fast_tracepoint
+	      || tpoint->type == static_tracepoint);
+
+  if (tpoint->cond != NULL && target_emit_ops () != NULL)
+    {
+      CORE_ADDR jentry, jump_entry;
+
+      jentry = jump_entry = get_jump_space_head ();
+
+      if (tpoint->cond != NULL)
+	{
+	  /* Pad to 8-byte alignment. (needed?)  */
+	  /* Actually this should be left for the target to
+	     decide.  */
+	  jentry = UALIGN (jentry, 8);
+
+	  compile_tracepoint_condition (tpoint, &jentry);
+	}
+
+      /* Pad to 8-byte alignment.  */
+      jentry = UALIGN (jentry, 8);
+      claim_jump_space (jentry - jump_entry);
+    }
+
+  target_tracepoint = *tpoint;
+
+  tpptr = target_malloc (sizeof (*tpoint));
+  tpoint->obj_addr_on_target = tpptr;
+
+  /* Write the whole object.  We'll fix up its pointers in a bit.
+     Assume no next for now.  This is fixed up above on the next
+     iteration, if there's any.  */
+  target_tracepoint.next = NULL;
+  /* Need to clear this here too, since we're downloading the
+     tracepoints before clearing our own copy.  */
+  target_tracepoint.hit_count = 0;
+
+  target_write_memory (tpptr, (unsigned char *) &target_tracepoint,
+			 sizeof (target_tracepoint));
+
+  if (tpoint->cond)
+    write_inferior_data_pointer (tpptr
+				 + offsetof (struct tracepoint, cond),
+				 download_agent_expr (tpoint->cond));
+
+  if (tpoint->numactions)
+    {
+      int i;
+      CORE_ADDR actions_array;
+
+      /* The pointers array.  */
+      actions_array
+	= target_malloc (sizeof (*tpoint->actions) * tpoint->numactions);
+      write_inferior_data_pointer (tpptr + offsetof (struct tracepoint,
+						     actions),
+				   actions_array);
+
+      /* Now for each pointer, download the action.  */
+      for (i = 0; i < tpoint->numactions; i++)
+	{
+	  struct tracepoint_action *action = tpoint->actions[i];
+	  CORE_ADDR ipa_action = tracepoint_action_download (action);
+
+	  if (ipa_action != 0)
+	    write_inferior_data_pointer (actions_array
+					 + i * sizeof (*tpoint->actions),
+					 ipa_action);
+	}
+    }
+}
+
+#define IPA_PROTO_FAST_TRACE_FLAG 0
+#define IPA_PROTO_FAST_TRACE_ADDR_ON_TARGET 2
+#define IPA_PROTO_FAST_TRACE_JUMP_PAD 10
+#define IPA_PROTO_FAST_TRACE_FJUMP_SIZE 18
+#define IPA_PROTO_FAST_TRACE_FJUMP_INSN 22
+
+/* Send a command to agent to download and install tracepoint TPOINT.  */
+
+static int
+tracepoint_send_agent (struct tracepoint *tpoint)
+{
+  char buf[IPA_CMD_BUF_SIZE];
+  char *p;
+  int i, ret;
+
+  p = buf;
+  strcpy (p, "FastTrace:");
+  p += 10;
+
+  COPY_FIELD_TO_BUF (p, tpoint, number);
+  COPY_FIELD_TO_BUF (p, tpoint, address);
+  COPY_FIELD_TO_BUF (p, tpoint, type);
+  COPY_FIELD_TO_BUF (p, tpoint, enabled);
+  COPY_FIELD_TO_BUF (p, tpoint, step_count);
+  COPY_FIELD_TO_BUF (p, tpoint, pass_count);
+  COPY_FIELD_TO_BUF (p, tpoint, numactions);
+  COPY_FIELD_TO_BUF (p, tpoint, hit_count);
+  COPY_FIELD_TO_BUF (p, tpoint, traceframe_usage);
+  COPY_FIELD_TO_BUF (p, tpoint, compiled_cond);
+  COPY_FIELD_TO_BUF (p, tpoint, orig_size);
+
+  /* condition */
+  p = agent_expr_send (p, tpoint->cond);
+
+  /* tracepoint_action */
+  for (i = 0; i < tpoint->numactions; i++)
+    {
+      struct tracepoint_action *action = tpoint->actions[i];
+
+      p[0] = action->type;
+      p = tracepoint_action_send (&p[1], action);
+    }
+
+  get_jump_space_head ();
+  /* Copy the value of GDB_JUMP_PAD_HEAD to command buffer, so that
+     agent can use jump pad from it.  */
+  if (tpoint->type == fast_tracepoint)
+    {
+      memcpy (p, &gdb_jump_pad_head, 8);
+      p += 8;
+    }
+
+  ret = run_inferior_command (buf, (int) (ptrdiff_t) (p - buf));
+  if (ret)
+    return ret;
+
+  if (!startswith (buf, "OK"))
+    return 1;
+
+  /* The value of tracepoint's target address is stored in BUF.  */
+  memcpy (&tpoint->obj_addr_on_target,
+	  &buf[IPA_PROTO_FAST_TRACE_ADDR_ON_TARGET], 8);
+
+  if (tpoint->type == fast_tracepoint)
+    {
+      unsigned char *insn
+	= (unsigned char *) &buf[IPA_PROTO_FAST_TRACE_FJUMP_INSN];
+      int fjump_size;
+
+     trace_debug ("agent: read from cmd_buf 0x%x 0x%x\n",
+		  (unsigned int) tpoint->obj_addr_on_target,
+		  (unsigned int) gdb_jump_pad_head);
+
+      memcpy (&gdb_jump_pad_head, &buf[IPA_PROTO_FAST_TRACE_JUMP_PAD], 8);
+
+      /* This has been done in agent.  We should also set up record for it.  */
+      memcpy (&fjump_size, &buf[IPA_PROTO_FAST_TRACE_FJUMP_SIZE], 4);
+      /* Wire it in.  */
+      tpoint->handle
+	= set_fast_tracepoint_jump (tpoint->address, insn, fjump_size);
+    }
+
+  return 0;
+}
+
+static void
+download_tracepoint (struct tracepoint *tpoint)
+{
+  struct tracepoint *tp, *tp_prev;
+
+  if (tpoint->type != fast_tracepoint
+      && tpoint->type != static_tracepoint)
+    return;
+
+  download_tracepoint_1 (tpoint);
+
+  /* Find the previous entry of TPOINT, which is fast tracepoint or
+     static tracepoint.  */
+  tp_prev = NULL;
+  for (tp = tracepoints; tp != tpoint; tp = tp->next)
+    {
+      if (tp->type == fast_tracepoint || tp->type == static_tracepoint)
+	tp_prev = tp;
+    }
+
+  if (tp_prev)
+    {
+      CORE_ADDR tp_prev_target_next_addr;
+
+      /* Insert TPOINT after TP_PREV in IPA.  */
+      if (read_inferior_data_pointer (tp_prev->obj_addr_on_target
+				      + offsetof (struct tracepoint, next),
+				      &tp_prev_target_next_addr))
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "error reading `tp_prev->next'");
+	}
+
+      /* tpoint->next = tp_prev->next */
+      write_inferior_data_pointer (tpoint->obj_addr_on_target
+				   + offsetof (struct tracepoint, next),
+				   tp_prev_target_next_addr);
+      /* tp_prev->next = tpoint */
+      write_inferior_data_pointer (tp_prev->obj_addr_on_target
+				   + offsetof (struct tracepoint, next),
+				   tpoint->obj_addr_on_target);
+    }
+  else
+    /* First object in list, set the head pointer in the
+       inferior.  */
+    write_inferior_data_pointer (ipa_sym_addrs.addr_tracepoints,
+				 tpoint->obj_addr_on_target);
+
+}
+
+static void
+download_trace_state_variables (void)
+{
+  CORE_ADDR ptr = 0, prev_ptr = 0;
+  struct trace_state_variable *tsv;
+
+  /* Start out empty.  */
+  write_inferior_data_pointer (ipa_sym_addrs.addr_trace_state_variables, 0);
+
+  for (tsv = trace_state_variables; tsv != NULL; tsv = tsv->next)
+    {
+      struct trace_state_variable target_tsv;
+
+      /* TSV's with a getter have been initialized equally in both the
+	 inferior and GDBserver.  Skip them.  */
+      if (tsv->getter != NULL)
+	continue;
+
+      target_tsv = *tsv;
+
+      prev_ptr = ptr;
+      ptr = target_malloc (sizeof (*tsv));
+
+      if (tsv == trace_state_variables)
+	{
+	  /* First object in list, set the head pointer in the
+	     inferior.  */
+
+	  write_inferior_data_pointer (ipa_sym_addrs.addr_trace_state_variables,
+				       ptr);
+	}
+      else
+	{
+	  write_inferior_data_pointer (prev_ptr
+				       + offsetof (struct trace_state_variable,
+						   next),
+				       ptr);
+	}
+
+      /* Write the whole object.  We'll fix up its pointers in a bit.
+	 Assume no next, fixup when needed.  */
+      target_tsv.next = NULL;
+
+      target_write_memory (ptr, (unsigned char *) &target_tsv,
+			     sizeof (target_tsv));
+
+      if (tsv->name != NULL)
+	{
+	  size_t size = strlen (tsv->name) + 1;
+	  CORE_ADDR name_addr = target_malloc (size);
+	  target_write_memory (name_addr,
+				 (unsigned char *) tsv->name, size);
+	  write_inferior_data_pointer (ptr
+				       + offsetof (struct trace_state_variable,
+						   name),
+				       name_addr);
+	}
+
+      gdb_assert (tsv->getter == NULL);
+    }
+
+  if (prev_ptr != 0)
+    {
+      /* Fixup the next pointer in the last item in the list.  */
+      write_inferior_data_pointer (prev_ptr
+				   + offsetof (struct trace_state_variable,
+					       next), 0);
+    }
+}
+
+/* Upload complete trace frames out of the IP Agent's trace buffer
+   into GDBserver's trace buffer.  This always uploads either all or
+   no trace frames.  This is the counter part of
+   `trace_alloc_trace_buffer'.  See its description of the atomic
+   syncing mechanism.  */
+
+static void
+upload_fast_traceframes (void)
+{
+  unsigned int ipa_traceframe_read_count, ipa_traceframe_write_count;
+  unsigned int ipa_traceframe_read_count_racy, ipa_traceframe_write_count_racy;
+  CORE_ADDR tf;
+  struct ipa_trace_buffer_control ipa_trace_buffer_ctrl;
+  unsigned int curr_tbctrl_idx;
+  unsigned int ipa_trace_buffer_ctrl_curr;
+  unsigned int ipa_trace_buffer_ctrl_curr_old;
+  CORE_ADDR ipa_trace_buffer_ctrl_addr;
+  struct breakpoint *about_to_request_buffer_space_bkpt;
+  CORE_ADDR ipa_trace_buffer_lo;
+  CORE_ADDR ipa_trace_buffer_hi;
+
+  if (read_inferior_uinteger (ipa_sym_addrs.addr_traceframe_read_count,
+			      &ipa_traceframe_read_count_racy))
+    {
+      /* This will happen in most targets if the current thread is
+	 running.  */
+      return;
+    }
+
+  if (read_inferior_uinteger (ipa_sym_addrs.addr_traceframe_write_count,
+			      &ipa_traceframe_write_count_racy))
+    return;
+
+  trace_debug ("ipa_traceframe_count (racy area): %d (w=%d, r=%d)",
+	       ipa_traceframe_write_count_racy
+	       - ipa_traceframe_read_count_racy,
+	       ipa_traceframe_write_count_racy,
+	       ipa_traceframe_read_count_racy);
+
+  if (ipa_traceframe_write_count_racy == ipa_traceframe_read_count_racy)
+    return;
+
+  about_to_request_buffer_space_bkpt
+    = set_breakpoint_at (ipa_sym_addrs.addr_about_to_request_buffer_space,
+			 NULL);
+
+  if (read_inferior_uinteger (ipa_sym_addrs.addr_trace_buffer_ctrl_curr,
+			      &ipa_trace_buffer_ctrl_curr))
+    return;
+
+  ipa_trace_buffer_ctrl_curr_old = ipa_trace_buffer_ctrl_curr;
+
+  curr_tbctrl_idx = ipa_trace_buffer_ctrl_curr & ~GDBSERVER_FLUSH_COUNT_MASK;
+
+  {
+    unsigned int prev, counter;
+
+    /* Update the token, with new counters, and the GDBserver stamp
+       bit.  Alway reuse the current TBC index.  */
+    prev = ipa_trace_buffer_ctrl_curr & GDBSERVER_FLUSH_COUNT_MASK_CURR;
+    counter = (prev + 0x100) & GDBSERVER_FLUSH_COUNT_MASK_CURR;
+
+    ipa_trace_buffer_ctrl_curr = (GDBSERVER_UPDATED_FLUSH_COUNT_BIT
+				  | (prev << 12)
+				  | counter
+				  | curr_tbctrl_idx);
+  }
+
+  if (write_inferior_uinteger (ipa_sym_addrs.addr_trace_buffer_ctrl_curr,
+			       ipa_trace_buffer_ctrl_curr))
+    return;
+
+  trace_debug ("Lib: Committed %08x -> %08x",
+	       ipa_trace_buffer_ctrl_curr_old,
+	       ipa_trace_buffer_ctrl_curr);
+
+  /* Re-read these, now that we've installed the
+     `about_to_request_buffer_space' breakpoint/lock.  A thread could
+     have finished a traceframe between the last read of these
+     counters and setting the breakpoint above.  If we start
+     uploading, we never want to leave this function with
+     traceframe_read_count != 0, otherwise, GDBserver could end up
+     incrementing the counter tokens more than once (due to event loop
+     nesting), which would break the IP agent's "effective" detection
+     (see trace_alloc_trace_buffer).  */
+  if (read_inferior_uinteger (ipa_sym_addrs.addr_traceframe_read_count,
+			      &ipa_traceframe_read_count))
+    return;
+  if (read_inferior_uinteger (ipa_sym_addrs.addr_traceframe_write_count,
+			      &ipa_traceframe_write_count))
+    return;
+
+  if (debug_threads)
+    {
+      trace_debug ("ipa_traceframe_count (blocked area): %d (w=%d, r=%d)",
+		   ipa_traceframe_write_count - ipa_traceframe_read_count,
+		   ipa_traceframe_write_count, ipa_traceframe_read_count);
+
+      if (ipa_traceframe_write_count != ipa_traceframe_write_count_racy
+	  || ipa_traceframe_read_count != ipa_traceframe_read_count_racy)
+	trace_debug ("note that ipa_traceframe_count's parts changed");
+    }
+
+  /* Get the address of the current TBC object (the IP agent has an
+     array of 3 such objects).  The index is stored in the TBC
+     token.  */
+  ipa_trace_buffer_ctrl_addr = ipa_sym_addrs.addr_trace_buffer_ctrl;
+  ipa_trace_buffer_ctrl_addr
+    += sizeof (struct ipa_trace_buffer_control) * curr_tbctrl_idx;
+
+  if (read_inferior_memory (ipa_trace_buffer_ctrl_addr,
+			    (unsigned char *) &ipa_trace_buffer_ctrl,
+			    sizeof (struct ipa_trace_buffer_control)))
+    return;
+
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_trace_buffer_lo,
+				  &ipa_trace_buffer_lo))
+    return;
+  if (read_inferior_data_pointer (ipa_sym_addrs.addr_trace_buffer_hi,
+				  &ipa_trace_buffer_hi))
+    return;
+
+  /* Offsets are easier to grok for debugging than raw addresses,
+     especially for the small trace buffer sizes that are useful for
+     testing.  */
+  trace_debug ("Lib: Trace buffer [%d] start=%d free=%d "
+	       "endfree=%d wrap=%d hi=%d",
+	       curr_tbctrl_idx,
+	       (int) (ipa_trace_buffer_ctrl.start - ipa_trace_buffer_lo),
+	       (int) (ipa_trace_buffer_ctrl.free - ipa_trace_buffer_lo),
+	       (int) (ipa_trace_buffer_ctrl.end_free - ipa_trace_buffer_lo),
+	       (int) (ipa_trace_buffer_ctrl.wrap - ipa_trace_buffer_lo),
+	       (int) (ipa_trace_buffer_hi - ipa_trace_buffer_lo));
+
+  /* Note that the IPA's buffer is always circular.  */
+
+#define IPA_FIRST_TRACEFRAME() (ipa_trace_buffer_ctrl.start)
+
+#define IPA_NEXT_TRACEFRAME_1(TF, TFOBJ)		\
+  ((TF) + sizeof (struct traceframe) + (TFOBJ)->data_size)
+
+#define IPA_NEXT_TRACEFRAME(TF, TFOBJ)					\
+  (IPA_NEXT_TRACEFRAME_1 (TF, TFOBJ)					\
+   - ((IPA_NEXT_TRACEFRAME_1 (TF, TFOBJ) >= ipa_trace_buffer_ctrl.wrap) \
+      ? (ipa_trace_buffer_ctrl.wrap - ipa_trace_buffer_lo)		\
+      : 0))
+
+  tf = IPA_FIRST_TRACEFRAME ();
+
+  while (ipa_traceframe_write_count - ipa_traceframe_read_count)
+    {
+      struct tracepoint *tpoint;
+      struct traceframe *tframe;
+      unsigned char *block;
+      struct traceframe ipa_tframe;
+
+      if (read_inferior_memory (tf, (unsigned char *) &ipa_tframe,
+				offsetof (struct traceframe, data)))
+	error ("Uploading: couldn't read traceframe at %s\n", paddress (tf));
+
+      if (ipa_tframe.tpnum == 0)
+	{
+	  internal_error (__FILE__, __LINE__,
+			  "Uploading: No (more) fast traceframes, but"
+			  " ipa_traceframe_count == %u??\n",
+			  ipa_traceframe_write_count
+			  - ipa_traceframe_read_count);
+	}
+
+      /* Note that this will be incorrect for multi-location
+	 tracepoints...  */
+      tpoint = find_next_tracepoint_by_number (NULL, ipa_tframe.tpnum);
+
+      tframe = add_traceframe (tpoint);
+      if (tframe == NULL)
+	{
+	  trace_buffer_is_full = 1;
+	  trace_debug ("Uploading: trace buffer is full");
+	}
+      else
+	{
+	  /* Copy the whole set of blocks in one go for now.  FIXME:
+	     split this in smaller blocks.  */
+	  block = add_traceframe_block (tframe, tpoint,
+					ipa_tframe.data_size);
+	  if (block != NULL)
+	    {
+	      if (read_inferior_memory (tf
+					+ offsetof (struct traceframe, data),
+					block, ipa_tframe.data_size))
+		error ("Uploading: Couldn't read traceframe data at %s\n",
+		       paddress (tf + offsetof (struct traceframe, data)));
+	    }
+
+	  trace_debug ("Uploading: traceframe didn't fit");
+	  finish_traceframe (tframe);
+	}
+
+      tf = IPA_NEXT_TRACEFRAME (tf, &ipa_tframe);
+
+      /* If we freed the traceframe that wrapped around, go back
+	 to the non-wrap case.  */
+      if (tf < ipa_trace_buffer_ctrl.start)
+	{
+	  trace_debug ("Lib: Discarding past the wraparound");
+	  ipa_trace_buffer_ctrl.wrap = ipa_trace_buffer_hi;
+	}
+      ipa_trace_buffer_ctrl.start = tf;
+      ipa_trace_buffer_ctrl.end_free = ipa_trace_buffer_ctrl.start;
+      ++ipa_traceframe_read_count;
+
+      if (ipa_trace_buffer_ctrl.start == ipa_trace_buffer_ctrl.free
+	  && ipa_trace_buffer_ctrl.start == ipa_trace_buffer_ctrl.end_free)
+	{
+	  trace_debug ("Lib: buffer is fully empty.  "
+		       "Trace buffer [%d] start=%d free=%d endfree=%d",
+		       curr_tbctrl_idx,
+		       (int) (ipa_trace_buffer_ctrl.start
+			      - ipa_trace_buffer_lo),
+		       (int) (ipa_trace_buffer_ctrl.free
+			      - ipa_trace_buffer_lo),
+		       (int) (ipa_trace_buffer_ctrl.end_free
+			      - ipa_trace_buffer_lo));
+
+	  ipa_trace_buffer_ctrl.start = ipa_trace_buffer_lo;
+	  ipa_trace_buffer_ctrl.free = ipa_trace_buffer_lo;
+	  ipa_trace_buffer_ctrl.end_free = ipa_trace_buffer_hi;
+	  ipa_trace_buffer_ctrl.wrap = ipa_trace_buffer_hi;
+	}
+
+      trace_debug ("Uploaded a traceframe\n"
+		   "Lib: Trace buffer [%d] start=%d free=%d "
+		   "endfree=%d wrap=%d hi=%d",
+		   curr_tbctrl_idx,
+		   (int) (ipa_trace_buffer_ctrl.start - ipa_trace_buffer_lo),
+		   (int) (ipa_trace_buffer_ctrl.free - ipa_trace_buffer_lo),
+		   (int) (ipa_trace_buffer_ctrl.end_free
+			  - ipa_trace_buffer_lo),
+		   (int) (ipa_trace_buffer_ctrl.wrap - ipa_trace_buffer_lo),
+		   (int) (ipa_trace_buffer_hi - ipa_trace_buffer_lo));
+    }
+
+  if (target_write_memory (ipa_trace_buffer_ctrl_addr,
+			     (unsigned char *) &ipa_trace_buffer_ctrl,
+			     sizeof (struct ipa_trace_buffer_control)))
+    return;
+
+  write_inferior_integer (ipa_sym_addrs.addr_traceframe_read_count,
+			  ipa_traceframe_read_count);
+
+  trace_debug ("Done uploading traceframes [%d]\n", curr_tbctrl_idx);
+
+  pause_all (1);
+
+  delete_breakpoint (about_to_request_buffer_space_bkpt);
+  about_to_request_buffer_space_bkpt = NULL;
+
+  unpause_all (1);
+
+  if (trace_buffer_is_full)
+    stop_tracing ();
+}
+#endif
+
+#ifdef IN_PROCESS_AGENT
+
+IP_AGENT_EXPORT_VAR int ust_loaded;
+IP_AGENT_EXPORT_VAR char cmd_buf[IPA_CMD_BUF_SIZE];
+
+#ifdef HAVE_UST
+
+/* Static tracepoints.  */
+
+/* UST puts a "struct tracepoint" in the global namespace, which
+   conflicts with our tracepoint.  Arguably, being a library, it
+   shouldn't take ownership of such a generic name.  We work around it
+   here.  */
+#define tracepoint ust_tracepoint
+#include <ust/ust.h>
+#undef tracepoint
+
+extern int serialize_to_text (char *outbuf, int bufsize,
+			      const char *fmt, va_list ap);
+
+#define GDB_PROBE_NAME "gdb"
+
+/* We dynamically search for the UST symbols instead of linking them
+   in.  This lets the user decide if the application uses static
+   tracepoints, instead of always pulling libust.so in.  This vector
+   holds pointers to all functions we care about.  */
+
+static struct
+{
+  int (*serialize_to_text) (char *outbuf, int bufsize,
+			    const char *fmt, va_list ap);
+
+  int (*ltt_probe_register) (struct ltt_available_probe *pdata);
+  int (*ltt_probe_unregister) (struct ltt_available_probe *pdata);
+
+  int (*ltt_marker_connect) (const char *channel, const char *mname,
+			     const char *pname);
+  int (*ltt_marker_disconnect) (const char *channel, const char *mname,
+				const char *pname);
+
+  void (*marker_iter_start) (struct marker_iter *iter);
+  void (*marker_iter_next) (struct marker_iter *iter);
+  void (*marker_iter_stop) (struct marker_iter *iter);
+  void (*marker_iter_reset) (struct marker_iter *iter);
+} ust_ops;
+
+#include <dlfcn.h>
+
+/* Cast through typeof to catch incompatible API changes.  Since UST
+   only builds with gcc, we can freely use gcc extensions here
+   too.  */
+#define GET_UST_SYM(SYM)					\
+  do								\
+    {								\
+      if (ust_ops.SYM == NULL)					\
+	ust_ops.SYM = (typeof (&SYM)) dlsym (RTLD_DEFAULT, #SYM);	\
+      if (ust_ops.SYM == NULL)					\
+	return 0;						\
+    } while (0)
+
+#define USTF(SYM) ust_ops.SYM
+
+/* Get pointers to all libust.so functions we care about.  */
+
+static int
+dlsym_ust (void)
+{
+  GET_UST_SYM (serialize_to_text);
+
+  GET_UST_SYM (ltt_probe_register);
+  GET_UST_SYM (ltt_probe_unregister);
+  GET_UST_SYM (ltt_marker_connect);
+  GET_UST_SYM (ltt_marker_disconnect);
+
+  GET_UST_SYM (marker_iter_start);
+  GET_UST_SYM (marker_iter_next);
+  GET_UST_SYM (marker_iter_stop);
+  GET_UST_SYM (marker_iter_reset);
+
+  ust_loaded = 1;
+  return 1;
+}
+
+/* Given an UST marker, return the matching gdb static tracepoint.
+   The match is done by address.  */
+
+static struct tracepoint *
+ust_marker_to_static_tracepoint (const struct marker *mdata)
+{
+  struct tracepoint *tpoint;
+
+  for (tpoint = tracepoints; tpoint; tpoint = tpoint->next)
+    {
+      if (tpoint->type != static_tracepoint)
+	continue;
+
+      if (tpoint->address == (uintptr_t) mdata->location)
+	return tpoint;
+    }
+
+  return NULL;
+}
+
+/* The probe function we install on lttng/ust markers.  Whenever a
+   probed ust marker is hit, this function is called.  This is similar
+   to gdb_collect, only for static tracepoints, instead of fast
+   tracepoints.  */
+
+static void
+gdb_probe (const struct marker *mdata, void *probe_private,
+	   struct registers *regs, void *call_private,
+	   const char *fmt, va_list *args)
+{
+  struct tracepoint *tpoint;
+  struct static_tracepoint_ctx ctx;
+  const struct target_desc *ipa_tdesc;
+
+  /* Don't do anything until the trace run is completely set up.  */
+  if (!tracing)
+    {
+      trace_debug ("gdb_probe: not tracing\n");
+      return;
+    }
+
+  ipa_tdesc = get_ipa_tdesc (ipa_tdesc_idx);
+  ctx.base.type = static_tracepoint;
+  ctx.regcache_initted = 0;
+  ctx.regs = regs;
+  ctx.fmt = fmt;
+  ctx.args = args;
+
+  /* Wrap the regblock in a register cache (in the stack, we don't
+     want to malloc here).  */
+  ctx.regspace = alloca (ipa_tdesc->registers_size);
+  if (ctx.regspace == NULL)
+    {
+      trace_debug ("Trace buffer block allocation failed, skipping");
+      return;
+    }
+
+  tpoint = ust_marker_to_static_tracepoint (mdata);
+  if (tpoint == NULL)
+    {
+      trace_debug ("gdb_probe: marker not known: "
+		   "loc:0x%p, ch:\"%s\",n:\"%s\",f:\"%s\"",
+		   mdata->location, mdata->channel,
+		   mdata->name, mdata->format);
+      return;
+    }
+
+  if (!tpoint->enabled)
+    {
+      trace_debug ("gdb_probe: tracepoint disabled");
+      return;
+    }
+
+  ctx.tpoint = tpoint;
+
+  trace_debug ("gdb_probe: collecting marker: "
+	       "loc:0x%p, ch:\"%s\",n:\"%s\",f:\"%s\"",
+	       mdata->location, mdata->channel,
+	       mdata->name, mdata->format);
+
+  /* Test the condition if present, and collect if true.  */
+  if (tpoint->cond == NULL
+      || condition_true_at_tracepoint ((struct tracepoint_hit_ctx *) &ctx,
+				       tpoint))
+    {
+      collect_data_at_tracepoint ((struct tracepoint_hit_ctx *) &ctx,
+				  tpoint->address, tpoint);
+
+      if (stopping_tracepoint
+	  || trace_buffer_is_full
+	  || expr_eval_result != expr_eval_no_error)
+	stop_tracing ();
+    }
+  else
+    {
+      /* If there was a condition and it evaluated to false, the only
+	 way we would stop tracing is if there was an error during
+	 condition expression evaluation.  */
+      if (expr_eval_result != expr_eval_no_error)
+	stop_tracing ();
+    }
+}
+
+/* Called if the gdb static tracepoint requested collecting "$_sdata",
+   static tracepoint string data.  This is a string passed to the
+   tracing library by the user, at the time of the tracepoint marker
+   call.  E.g., in the UST marker call:
+
+     trace_mark (ust, bar33, "str %s", "FOOBAZ");
+
+   the collected data is "str FOOBAZ".
+*/
+
+static void
+collect_ust_data_at_tracepoint (struct tracepoint_hit_ctx *ctx,
+				struct traceframe *tframe)
+{
+  struct static_tracepoint_ctx *umd = (struct static_tracepoint_ctx *) ctx;
+  unsigned char *bufspace;
+  int size;
+  va_list copy;
+  unsigned short blocklen;
+
+  if (umd == NULL)
+    {
+      trace_debug ("Wanted to collect static trace data, "
+		   "but there's no static trace data");
+      return;
+    }
+
+  va_copy (copy, *umd->args);
+  size = USTF(serialize_to_text) (NULL, 0, umd->fmt, copy);
+  va_end (copy);
+
+  trace_debug ("Want to collect ust data");
+
+  /* 'S' + size + string */
+  bufspace = add_traceframe_block (tframe, umd->tpoint,
+				   1 + sizeof (blocklen) + size + 1);
+  if (bufspace == NULL)
+    {
+      trace_debug ("Trace buffer block allocation failed, skipping");
+      return;
+    }
+
+  /* Identify a static trace data block.  */
+  *bufspace = 'S';
+
+  blocklen = size + 1;
+  memcpy (bufspace + 1, &blocklen, sizeof (blocklen));
+
+  va_copy (copy, *umd->args);
+  USTF(serialize_to_text) ((char *) bufspace + 1 + sizeof (blocklen),
+			   size + 1, umd->fmt, copy);
+  va_end (copy);
+
+  trace_debug ("Storing static tracepoint data in regblock: %s",
+	       bufspace + 1 + sizeof (blocklen));
+}
+
+/* The probe to register with lttng/ust.  */
+static struct ltt_available_probe gdb_ust_probe =
+  {
+    GDB_PROBE_NAME,
+    NULL,
+    gdb_probe,
+  };
+
+#endif /* HAVE_UST */
+#endif /* IN_PROCESS_AGENT */
+
+#ifndef IN_PROCESS_AGENT
+
+/* Ask the in-process agent to run a command.  Since we don't want to
+   have to handle the IPA hitting breakpoints while running the
+   command, we pause all threads, remove all breakpoints, and then set
+   the helper thread re-running.  We communicate with the helper
+   thread by means of direct memory xfering, and a socket for
+   synchronization.  */
+
+static int
+run_inferior_command (char *cmd, int len)
+{
+  int err = -1;
+  int pid = current_ptid.pid ();
+
+  trace_debug ("run_inferior_command: running: %s", cmd);
+
+  pause_all (0);
+  uninsert_all_breakpoints ();
+
+  err = agent_run_command (pid, (const char *) cmd, len);
+
+  reinsert_all_breakpoints ();
+  unpause_all (0);
+
+  return err;
+}
+
+#else /* !IN_PROCESS_AGENT */
+
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#ifndef UNIX_PATH_MAX
+#define UNIX_PATH_MAX sizeof(((struct sockaddr_un *) NULL)->sun_path)
+#endif
+
+/* Where we put the socked used for synchronization.  */
+#define SOCK_DIR P_tmpdir
+
+/* Thread ID of the helper thread.  GDBserver reads this to know which
+   is the help thread.  This is an LWP id on Linux.  */
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR int helper_thread_id;
+EXTERN_C_POP
+
+static int
+init_named_socket (const char *name)
+{
+  int result, fd;
+  struct sockaddr_un addr;
+
+  result = fd = socket (PF_UNIX, SOCK_STREAM, 0);
+  if (result == -1)
+    {
+      warning ("socket creation failed: %s", safe_strerror (errno));
+      return -1;
+    }
+
+  addr.sun_family = AF_UNIX;
+
+  strncpy (addr.sun_path, name, UNIX_PATH_MAX);
+  addr.sun_path[UNIX_PATH_MAX - 1] = '\0';
+
+  result = access (name, F_OK);
+  if (result == 0)
+    {
+      /* File exists.  */
+      result = unlink (name);
+      if (result == -1)
+	{
+	  warning ("unlink failed: %s", safe_strerror (errno));
+	  close (fd);
+	  return -1;
+	}
+      warning ("socket %s already exists; overwriting", name);
+    }
+
+  result = bind (fd, (struct sockaddr *) &addr, sizeof (addr));
+  if (result == -1)
+    {
+      warning ("bind failed: %s", safe_strerror (errno));
+      close (fd);
+      return -1;
+    }
+
+  result = listen (fd, 1);
+  if (result == -1)
+    {
+      warning ("listen: %s", safe_strerror (errno));
+      close (fd);
+      return -1;
+    }
+
+  return fd;
+}
+
+static char agent_socket_name[UNIX_PATH_MAX];
+
+static int
+gdb_agent_socket_init (void)
+{
+  int result, fd;
+
+  result = xsnprintf (agent_socket_name, UNIX_PATH_MAX, "%s/gdb_ust%d",
+		      SOCK_DIR, getpid ());
+  if (result >= UNIX_PATH_MAX)
+    {
+      trace_debug ("string overflow allocating socket name");
+      return -1;
+    }
+
+  fd = init_named_socket (agent_socket_name);
+  if (fd < 0)
+    warning ("Error initializing named socket (%s) for communication with the "
+	     "ust helper thread. Check that directory exists and that it "
+	     "is writable.", agent_socket_name);
+
+  return fd;
+}
+
+#ifdef HAVE_UST
+
+/* The next marker to be returned on a qTsSTM command.  */
+static const struct marker *next_st;
+
+/* Returns the first known marker.  */
+
+struct marker *
+first_marker (void)
+{
+  struct marker_iter iter;
+
+  USTF(marker_iter_reset) (&iter);
+  USTF(marker_iter_start) (&iter);
+
+  return iter.marker;
+}
+
+/* Returns the marker following M.  */
+
+const struct marker *
+next_marker (const struct marker *m)
+{
+  struct marker_iter iter;
+
+  USTF(marker_iter_reset) (&iter);
+  USTF(marker_iter_start) (&iter);
+
+  for (; iter.marker != NULL; USTF(marker_iter_next) (&iter))
+    {
+      if (iter.marker == m)
+	{
+	  USTF(marker_iter_next) (&iter);
+	  return iter.marker;
+	}
+    }
+
+  return NULL;
+}
+
+/* Return an hexstr version of the STR C string, fit for sending to
+   GDB.  */
+
+static char *
+cstr_to_hexstr (const char *str)
+{
+  int len = strlen (str);
+  char *hexstr = xmalloc (len * 2 + 1);
+  bin2hex ((gdb_byte *) str, hexstr, len);
+  return hexstr;
+}
+
+/* Compose packet that is the response to the qTsSTM/qTfSTM/qTSTMat
+   packets.  */
+
+static void
+response_ust_marker (char *packet, const struct marker *st)
+{
+  char *strid, *format, *tmp;
+
+  next_st = next_marker (st);
+
+  tmp = xmalloc (strlen (st->channel) + 1 +
+		 strlen (st->name) + 1);
+  sprintf (tmp, "%s/%s", st->channel, st->name);
+
+  strid = cstr_to_hexstr (tmp);
+  free (tmp);
+
+  format = cstr_to_hexstr (st->format);
+
+  sprintf (packet, "m%s:%s:%s",
+	   paddress ((uintptr_t) st->location),
+	   strid,
+	   format);
+
+  free (strid);
+  free (format);
+}
+
+/* Return the first static tracepoint, and initialize the state
+   machine that will iterate through all the static tracepoints.  */
+
+static void
+cmd_qtfstm (char *packet)
+{
+  trace_debug ("Returning first trace state variable definition");
+
+  if (first_marker ())
+    response_ust_marker (packet, first_marker ());
+  else
+    strcpy (packet, "l");
+}
+
+/* Return additional trace state variable definitions. */
+
+static void
+cmd_qtsstm (char *packet)
+{
+  trace_debug ("Returning static tracepoint");
+
+  if (next_st)
+    response_ust_marker (packet, next_st);
+  else
+    strcpy (packet, "l");
+}
+
+/* Disconnect the GDB probe from a marker at a given address.  */
+
+static void
+unprobe_marker_at (char *packet)
+{
+  char *p = packet;
+  ULONGEST address;
+  struct marker_iter iter;
+
+  p += sizeof ("unprobe_marker_at:") - 1;
+
+  p = unpack_varlen_hex (p, &address);
+
+  USTF(marker_iter_reset) (&iter);
+  USTF(marker_iter_start) (&iter);
+  for (; iter.marker != NULL; USTF(marker_iter_next) (&iter))
+    if ((uintptr_t ) iter.marker->location == address)
+      {
+	int result;
+
+	result = USTF(ltt_marker_disconnect) (iter.marker->channel,
+					      iter.marker->name,
+					      GDB_PROBE_NAME);
+	if (result < 0)
+	  warning ("could not disable marker %s/%s",
+		   iter.marker->channel, iter.marker->name);
+	break;
+      }
+}
+
+/* Connect the GDB probe to a marker at a given address.  */
+
+static int
+probe_marker_at (char *packet)
+{
+  char *p = packet;
+  ULONGEST address;
+  struct marker_iter iter;
+  struct marker *m;
+
+  p += sizeof ("probe_marker_at:") - 1;
+
+  p = unpack_varlen_hex (p, &address);
+
+  USTF(marker_iter_reset) (&iter);
+
+  for (USTF(marker_iter_start) (&iter), m = iter.marker;
+       m != NULL;
+       USTF(marker_iter_next) (&iter), m = iter.marker)
+    if ((uintptr_t ) m->location == address)
+      {
+	int result;
+
+	trace_debug ("found marker for address.  "
+		     "ltt_marker_connect (marker = %s/%s)",
+		     m->channel, m->name);
+
+	result = USTF(ltt_marker_connect) (m->channel, m->name,
+					   GDB_PROBE_NAME);
+	if (result && result != -EEXIST)
+	  trace_debug ("ltt_marker_connect (marker = %s/%s, errno = %d)",
+		       m->channel, m->name, -result);
+
+	if (result < 0)
+	  {
+	    sprintf (packet, "E.could not connect marker: channel=%s, name=%s",
+		     m->channel, m->name);
+	    return -1;
+	  }
+
+	strcpy (packet, "OK");
+	return 0;
+      }
+
+  sprintf (packet, "E.no marker found at 0x%s", paddress (address));
+  return -1;
+}
+
+static int
+cmd_qtstmat (char *packet)
+{
+  char *p = packet;
+  ULONGEST address;
+  struct marker_iter iter;
+  struct marker *m;
+
+  p += sizeof ("qTSTMat:") - 1;
+
+  p = unpack_varlen_hex (p, &address);
+
+  USTF(marker_iter_reset) (&iter);
+
+  for (USTF(marker_iter_start) (&iter), m = iter.marker;
+       m != NULL;
+       USTF(marker_iter_next) (&iter), m = iter.marker)
+    if ((uintptr_t ) m->location == address)
+      {
+	response_ust_marker (packet, m);
+	return 0;
+      }
+
+  strcpy (packet, "l");
+  return -1;
+}
+
+static void
+gdb_ust_init (void)
+{
+  if (!dlsym_ust ())
+    return;
+
+  USTF(ltt_probe_register) (&gdb_ust_probe);
+}
+
+#endif /* HAVE_UST */
+
+#include <sys/syscall.h>
+
+static void
+gdb_agent_remove_socket (void)
+{
+  unlink (agent_socket_name);
+}
+
+/* Helper thread of agent.  */
+
+static void *
+gdb_agent_helper_thread (void *arg)
+{
+  int listen_fd;
+
+  atexit (gdb_agent_remove_socket);
+
+  while (1)
+    {
+      listen_fd = gdb_agent_socket_init ();
+
+      if (helper_thread_id == 0)
+	helper_thread_id = syscall (SYS_gettid);
+
+      if (listen_fd == -1)
+	{
+	  warning ("could not create sync socket");
+	  break;
+	}
+
+      while (1)
+	{
+	  socklen_t tmp;
+	  struct sockaddr_un sockaddr;
+	  int fd;
+	  char buf[1];
+	  int ret;
+	  int stop_loop = 0;
+
+	  tmp = sizeof (sockaddr);
+
+	  do
+	    {
+	      fd = accept (listen_fd, (struct sockaddr *) &sockaddr, &tmp);
+	    }
+	  /* It seems an ERESTARTSYS can escape out of accept.  */
+	  while (fd == -512 || (fd == -1 && errno == EINTR));
+
+	  if (fd < 0)
+	    {
+	      warning ("Accept returned %d, error: %s",
+		       fd, safe_strerror (errno));
+	      break;
+	    }
+
+	  do
+	    {
+	      ret = read (fd, buf, 1);
+	    } while (ret == -1 && errno == EINTR);
+
+	  if (ret == -1)
+	    {
+	      warning ("reading socket (fd=%d) failed with %s",
+		       fd, safe_strerror (errno));
+	      close (fd);
+	      break;
+	    }
+
+	  if (cmd_buf[0])
+	    {
+	      if (startswith (cmd_buf, "close"))
+		{
+		  stop_loop = 1;
+		}
+#ifdef HAVE_UST
+	      else if (strcmp ("qTfSTM", cmd_buf) == 0)
+		{
+		  cmd_qtfstm (cmd_buf);
+		}
+	      else if (strcmp ("qTsSTM", cmd_buf) == 0)
+		{
+		  cmd_qtsstm (cmd_buf);
+		}
+	      else if (startswith (cmd_buf, "unprobe_marker_at:"))
+		{
+		  unprobe_marker_at (cmd_buf);
+		}
+	      else if (startswith (cmd_buf, "probe_marker_at:"))
+		{
+		  probe_marker_at (cmd_buf);
+		}
+	      else if (startswith (cmd_buf, "qTSTMat:"))
+		{
+		  cmd_qtstmat (cmd_buf);
+		}
+#endif /* HAVE_UST */
+	    }
+
+	  /* Fix compiler's warning: ignoring return value of 'write'.  */
+	  ret = write (fd, buf, 1);
+	  close (fd);
+
+	  if (stop_loop)
+	    {
+	      close (listen_fd);
+	      unlink (agent_socket_name);
+
+	      /* Sleep endlessly to wait the whole inferior stops.  This
+		 thread can not exit because GDB or GDBserver may still need
+		 'current_thread' (representing this thread) to access
+		 inferior memory.  Otherwise, this thread exits earlier than
+		 other threads, and 'current_thread' is set to NULL.  */
+	      while (1)
+		sleep (10);
+	    }
+	}
+    }
+
+  return NULL;
+}
+
+#include <signal.h>
+#include <pthread.h>
+
+EXTERN_C_PUSH
+IP_AGENT_EXPORT_VAR int gdb_agent_capability = AGENT_CAPA_STATIC_TRACE;
+EXTERN_C_POP
+
+static void
+gdb_agent_init (void)
+{
+  int res;
+  pthread_t thread;
+  sigset_t new_mask;
+  sigset_t orig_mask;
+
+  /* We want the helper thread to be as transparent as possible, so
+     have it inherit an all-signals-blocked mask.  */
+
+  sigfillset (&new_mask);
+  res = pthread_sigmask (SIG_SETMASK, &new_mask, &orig_mask);
+  if (res)
+    perror_with_name ("pthread_sigmask (1)");
+
+  res = pthread_create (&thread,
+			NULL,
+			gdb_agent_helper_thread,
+			NULL);
+
+  res = pthread_sigmask (SIG_SETMASK, &orig_mask, NULL);
+  if (res)
+    perror_with_name ("pthread_sigmask (2)");
+
+  while (helper_thread_id == 0)
+    usleep (1);
+
+#ifdef HAVE_UST
+  gdb_ust_init ();
+#endif
+}
+
+#include <sys/mman.h>
+
+IP_AGENT_EXPORT_VAR char *gdb_tp_heap_buffer;
+IP_AGENT_EXPORT_VAR char *gdb_jump_pad_buffer;
+IP_AGENT_EXPORT_VAR char *gdb_jump_pad_buffer_end;
+IP_AGENT_EXPORT_VAR char *gdb_trampoline_buffer;
+IP_AGENT_EXPORT_VAR char *gdb_trampoline_buffer_end;
+IP_AGENT_EXPORT_VAR char *gdb_trampoline_buffer_error;
+
+/* Record the result of getting buffer space for fast tracepoint
+   trampolines.  Any error message is copied, since caller may not be
+   using persistent storage.  */
+
+void
+set_trampoline_buffer_space (CORE_ADDR begin, CORE_ADDR end, char *errmsg)
+{
+  gdb_trampoline_buffer = (char *) (uintptr_t) begin;
+  gdb_trampoline_buffer_end = (char *) (uintptr_t) end;
+  if (errmsg)
+    strncpy (gdb_trampoline_buffer_error, errmsg, 99);
+  else
+    strcpy (gdb_trampoline_buffer_error, "no buffer passed");
+}
+
+static void __attribute__ ((constructor))
+initialize_tracepoint_ftlib (void)
+{
+  initialize_tracepoint ();
+
+  gdb_agent_init ();
+}
+
+#ifndef HAVE_GETAUXVAL
+/* Retrieve the value of TYPE from the auxiliary vector.  If TYPE is not
+   found, 0 is returned.  This function is provided if glibc is too old.  */
+
+unsigned long
+getauxval (unsigned long type)
+{
+  unsigned long data[2];
+  FILE *f = fopen ("/proc/self/auxv", "r");
+  unsigned long value = 0;
+
+  if (f == NULL)
+    return 0;
+
+  while (fread (data, sizeof (data), 1, f) > 0)
+    {
+      if (data[0] == type)
+	{
+	  value = data[1];
+	  break;
+	}
+    }
+
+  fclose (f);
+  return value;
+}
+#endif
+
+#endif /* IN_PROCESS_AGENT */
+
+/* Return a timestamp, expressed as microseconds of the usual Unix
+   time.  (As the result is a 64-bit number, it will not overflow any
+   time soon.)  */
+
+static LONGEST
+get_timestamp (void)
+{
+  using namespace std::chrono;
+
+  steady_clock::time_point now = steady_clock::now ();
+  return duration_cast<microseconds> (now.time_since_epoch ()).count ();
+}
+
+void
+initialize_tracepoint (void)
+{
+  /* Start with the default size.  */
+  init_trace_buffer (DEFAULT_TRACE_BUFFER_SIZE);
+
+  /* Wire trace state variable 1 to be the timestamp.  This will be
+     uploaded to GDB upon connection and become one of its trace state
+     variables.  (In case you're wondering, if GDB already has a trace
+     variable numbered 1, it will be renumbered.)  */
+  create_trace_state_variable (1, 0);
+  set_trace_state_variable_name (1, "trace_timestamp");
+  set_trace_state_variable_getter (1, get_timestamp);
+
+#ifdef IN_PROCESS_AGENT
+  {
+    int pagesize;
+    size_t jump_pad_size;
+
+    pagesize = sysconf (_SC_PAGE_SIZE);
+    if (pagesize == -1)
+      perror_with_name ("sysconf");
+
+#define SCRATCH_BUFFER_NPAGES 20
+
+    jump_pad_size = pagesize * SCRATCH_BUFFER_NPAGES;
+
+    gdb_tp_heap_buffer = (char *) xmalloc (5 * 1024 * 1024);
+    gdb_jump_pad_buffer = (char *) alloc_jump_pad_buffer (jump_pad_size);
+    if (gdb_jump_pad_buffer == NULL)
+      perror_with_name ("mmap");
+    gdb_jump_pad_buffer_end = gdb_jump_pad_buffer + jump_pad_size;
+  }
+
+  gdb_trampoline_buffer = gdb_trampoline_buffer_end = 0;
+
+  /* It's not a fatal error for something to go wrong with trampoline
+     buffer setup, but it can be mysterious, so create a channel to
+     report back on what went wrong, using a fixed size since we may
+     not be able to allocate space later when the problem occurs.  */
+  gdb_trampoline_buffer_error = (char *) xmalloc (IPA_BUFSIZ);
+
+  strcpy (gdb_trampoline_buffer_error, "No errors reported");
+
+  initialize_low_tracepoint ();
+#endif
+}