ovs-vswitchd: Export system stats through Open_vSwitch table.

This is intended to provide controllers enough information to determine
whether a switch is overloaded or busted, to enable them to spread load
fairly across a group of switches.

Feature #2421.

CC: Peter Balland <peter@nicira.com>

1 files changed, 503 insertions, 0 deletions

diff --git a/vswitchd/system-stats.c b/vswitchd/system-stats.c
new file mode 100644
index 00000000..11b2fbed
--- /dev/null
+++ b/vswitchd/system-stats.c
@@ -0,0 +1,503 @@
+/* Copyright (c) 2010 Nicira Networks
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include <assert.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <errno.h>
+#if HAVE_MNTENT_H
+#include <mntent.h>
+#endif
+#include <signal.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#if HAVE_SYS_STATVFS_H
+#include <sys/statvfs.h>
+#endif
+#include <unistd.h>
+
+#include "daemon.h"
+#include "dirs.h"
+#include "dynamic-string.h"
+#include "shash.h"
+#include "system-stats.h"
+#include "timeval.h"
+#include "vlog.h"
+
+VLOG_DEFINE_THIS_MODULE(system_stats)
+
+/* #ifdefs make it a pain to maintain code: you have to try to build both ways.
+ * Thus, this file tries to compile as much of the code as possible regardless
+ * of the target, by writing "if (LINUX)" instead of "#ifdef __linux__" where
+ * this is possible. */
+#ifdef __linux__
+#include <asm/param.h>
+#define LINUX 1
+#else
+#define LINUX 0
+#endif
+
+static void
+get_cpu_cores(struct shash *stats)
+{
+    long int n_cores = sysconf(_SC_NPROCESSORS_ONLN);
+    if (n_cores > 0) {
+        shash_add(stats, "cpu", xasprintf("%ld", n_cores));
+    }
+}
+
+static void
+get_load_average(struct shash *stats OVS_UNUSED)
+{
+#if HAVE_GETLOADAVG
+    double loadavg[3];
+
+    if (getloadavg(loadavg, 3) == 3) {
+        shash_add(stats, "load_average",
+                  xasprintf("%.2f,%.2f,%.2f",
+                            loadavg[0], loadavg[1], loadavg[2]));
+    }
+#endif
+}
+
+static unsigned int
+get_page_size(void)
+{
+    static unsigned int cached;
+
+    if (!cached) {
+        long int value = sysconf(_SC_PAGESIZE);
+        if (value >= 0) {
+            cached = value;
+        }
+    }
+
+    return cached;
+}
+
+static void
+get_memory_stats(struct shash *stats)
+{
+    if (!LINUX) {
+        unsigned int pagesize = get_page_size();
+        long int phys_pages = sysconf(_SC_PHYS_PAGES);
+        long int avphys_pages = sysconf(_SC_AVPHYS_PAGES);
+        int mem_total, mem_used;
+
+        if (pagesize <= 0 || phys_pages <= 0 || avphys_pages <= 0) {
+            return;
+        }
+
+        mem_total = phys_pages * (pagesize / 1024);
+        mem_used = (phys_pages - avphys_pages) * (pagesize / 1024);
+        shash_add(stats, "memory", xasprintf("%d,%d", mem_total, mem_used));
+    } else {
+        static const char file_name[] = "/proc/meminfo";
+        int mem_used, mem_cache, swap_used;
+        int mem_free = 0;
+        int buffers = 0;
+        int cached = 0;
+        int swap_free = 0;
+        int mem_total = 0;
+        int swap_total = 0;
+        struct shash dict;
+        char line[128];
+        FILE *stream;
+
+        stream = fopen(file_name, "r");
+        if (!stream) {
+            VLOG_WARN_ONCE("%s: open failed (%s)", file_name, strerror(errno));
+            return;
+        }
+
+        shash_init(&dict);
+        shash_add(&dict, "MemTotal", &mem_total);
+        shash_add(&dict, "MemFree", &mem_free);
+        shash_add(&dict, "Buffers", &buffers);
+        shash_add(&dict, "Cached", &cached);
+        shash_add(&dict, "SwapTotal", &swap_total);
+        shash_add(&dict, "SwapFree", &swap_free);
+        while (fgets(line, sizeof line, stream)) {
+            char key[16];
+            int value;
+
+            if (sscanf(line, "%15[^:]: %u", key, &value) == 2) {
+                int *valuep = shash_find_data(&dict, key);
+                if (valuep) {
+                    *valuep = value;
+                }
+            }
+        }
+        fclose(stream);
+        shash_destroy(&dict);
+
+        mem_used = mem_total - mem_free;
+        mem_cache = buffers + cached;
+        swap_used = swap_total - swap_free;
+        shash_add(stats, "memory",
+                  xasprintf("%d,%d,%d,%d,%d", mem_total, mem_used, mem_cache,
+                            swap_total, swap_used));
+    }
+}
+
+/* Returns the time at which the system booted, as the number of milliseconds
+ * since the epoch, or 0 if the time of boot cannot be determined. */
+static long long int
+get_boot_time(void)
+{
+    static long long int cache_expiration = LLONG_MIN;
+    static long long int boot_time;
+
+    assert(LINUX);
+
+    if (time_msec() >= cache_expiration) {
+        static const char stat_file[] = "/proc/stat";
+        char line[128];
+        FILE *stream;
+
+        cache_expiration = time_msec() + 5 * 1000;
+
+        stream = fopen(stat_file, "r");
+        if (!stream) {
+            VLOG_ERR_ONCE("%s: open failed (%s)", stat_file, strerror(errno));
+            return boot_time;
+        }
+
+        while (fgets(line, sizeof line, stream)) {
+            long long int btime;
+            if (sscanf(line, "btime %lld", &btime) == 1) {
+                boot_time = btime * 1000;
+                goto done;
+            }
+        }
+        VLOG_ERR_ONCE("%s: btime not found", stat_file);
+    done:
+        fclose(stream);
+    }
+    return boot_time;
+}
+
+static unsigned long long int
+ticks_to_ms(unsigned long long int ticks)
+{
+    assert(LINUX);
+
+#ifndef USER_HZ
+#define USER_HZ 100
+#endif
+
+#if USER_HZ == 100              /* Common case. */
+    return ticks * (1000 / USER_HZ);
+#else  /* Alpha and some other architectures.  */
+    double factor = 1000.0 / USER_HZ;
+    return ticks * factor + 0.5;
+#endif
+}
+
+struct raw_process_info {
+    unsigned long int vsz;      /* Virtual size, in kB. */
+    unsigned long int rss;      /* Resident set size, in kB. */
+    long long int uptime;       /* ms since started. */
+    long long int cputime;      /* ms of CPU used during 'uptime'. */
+    pid_t ppid;                 /* Parent. */
+    char name[18];              /* Name (surrounded by parentheses). */
+};
+
+static bool
+get_raw_process_info(pid_t pid, struct raw_process_info *raw)
+{
+    unsigned long long int vsize, rss, start_time, utime, stime;
+    long long int start_msec;
+    unsigned long ppid;
+    char file_name[128];
+    FILE *stream;
+    int n;
+
+    assert(LINUX);
+
+    sprintf(file_name, "/proc/%lu/stat", (unsigned long int) pid);
+    stream = fopen(file_name, "r");
+    if (!stream) {
+        VLOG_ERR_ONCE("%s: open failed (%s)", file_name, strerror(errno));
+        return false;
+    }
+
+    n = fscanf(stream,
+               "%*d "           /* (1. pid) */
+               "%17s "          /* 2. process name */
+               "%*c "           /* (3. state) */
+               "%lu "           /* 4. ppid */
+               "%*d "           /* (5. pgid) */
+               "%*d "           /* (6. sid) */
+               "%*d "           /* (7. tty_nr) */
+               "%*d "           /* (8. tty_pgrp) */
+               "%*u "           /* (9. flags) */
+               "%*u "           /* (10. min_flt) */
+               "%*u "           /* (11. cmin_flt) */
+               "%*u "           /* (12. maj_flt) */
+               "%*u "           /* (13. cmaj_flt) */
+               "%llu "          /* 14. utime */
+               "%llu "          /* 15. stime */
+               "%*d "           /* (16. cutime) */
+               "%*d "           /* (17. cstime) */
+               "%*d "           /* (18. priority) */
+               "%*d "           /* (19. nice) */
+               "%*d "           /* (20. num_threads) */
+               "%*d "           /* (21. always 0) */
+               "%llu "          /* 22. start_time */
+               "%llu "          /* 23. vsize */
+               "%llu "          /* 24. rss */
+#if 0
+               /* These are here for documentation but #if'd out to save
+                * actually parsing them from the stream for no benefit. */
+               "%*lu "          /* (25. rsslim) */
+               "%*lu "          /* (26. start_code) */
+               "%*lu "          /* (27. end_code) */
+               "%*lu "          /* (28. start_stack) */
+               "%*lu "          /* (29. esp) */
+               "%*lu "          /* (30. eip) */
+               "%*lu "          /* (31. pending signals) */
+               "%*lu "          /* (32. blocked signals) */
+               "%*lu "          /* (33. ignored signals) */
+               "%*lu "          /* (34. caught signals) */
+               "%*lu "          /* (35. whcan) */
+               "%*lu "          /* (36. always 0) */
+               "%*lu "          /* (37. always 0) */
+               "%*d "           /* (38. exit_signal) */
+               "%*d "           /* (39. task_cpu) */
+               "%*u "           /* (40. rt_priority) */
+               "%*u "           /* (41. policy) */
+               "%*llu "         /* (42. blkio_ticks) */
+               "%*lu "          /* (43. gtime) */
+               "%*ld"           /* (44. cgtime) */
+#endif
+               , raw->name, &ppid, &utime, &stime, &start_time, &vsize, &rss);
+    fclose(stream);
+    if (n != 7) {
+        VLOG_ERR_ONCE("%s: fscanf failed", file_name);
+        return false;
+    }
+
+    start_msec = get_boot_time() + ticks_to_ms(start_time);
+
+    raw->vsz = vsize / 1024;
+    raw->rss = rss * (getpagesize() / 1024);
+    raw->uptime = time_wall_msec() - start_msec;
+    raw->cputime = ticks_to_ms(utime + stime);
+    raw->ppid = ppid;
+
+    return true;
+}
+
+static int
+count_crashes(pid_t pid)
+{
+    char file_name[128];
+    const char *paren;
+    char line[128];
+    int crashes = 0;
+    FILE *stream;
+
+    assert(LINUX);
+
+    sprintf(file_name, "/proc/%lu/cmdline", (unsigned long int) pid);
+    stream = fopen(file_name, "r");
+    if (!stream) {
+        VLOG_WARN_ONCE("%s: open failed (%s)", file_name, strerror(errno));
+        goto exit;
+    }
+
+    if (!fgets(line, sizeof line, stream)) {
+        VLOG_WARN_ONCE("%s: read failed (%s)", file_name,
+                       feof(stream) ? "end of file" : strerror(errno));
+        goto exit_close;
+    }
+
+    paren = strchr(line, '(');
+    if (paren) {
+        int x;
+        if (sscanf(paren + 1, "%d", &x) == 1) {
+            crashes = x;
+        }
+    }
+
+exit_close:
+    fclose(stream);
+exit:
+    return crashes;
+}
+
+struct process_info {
+    unsigned long int vsz;      /* Virtual size, in kB. */
+    unsigned long int rss;      /* Resident set size, in kB. */
+    long long int booted;       /* ms since monitor started. */
+    int crashes;                /* # of crashes (usually 0). */
+    long long int uptime;       /* ms since last (re)started by monitor. */
+    long long int cputime;      /* ms of CPU used during 'uptime'. */
+};
+
+static bool
+get_process_info(pid_t pid, struct process_info *pinfo)
+{
+    struct raw_process_info child;
+
+    assert(LINUX);
+    if (!get_raw_process_info(pid, &child)) {
+        return false;
+    }
+
+    pinfo->vsz = child.vsz;
+    pinfo->rss = child.rss;
+    pinfo->booted = child.uptime;
+    pinfo->crashes = 0;
+    pinfo->uptime = child.uptime;
+    pinfo->cputime = child.cputime;
+
+    if (child.ppid) {
+        struct raw_process_info parent;
+
+        get_raw_process_info(child.ppid, &parent);
+        if (!strcmp(child.name, parent.name)) {
+            pinfo->booted = parent.uptime;
+            pinfo->crashes = count_crashes(child.ppid);
+        }
+    }
+
+    return true;
+}
+
+static void
+get_process_stats(struct shash *stats)
+{
+    struct dirent *de;
+    DIR *dir;
+
+    dir = opendir(ovs_rundir);
+    if (!dir) {
+        VLOG_ERR_ONCE("%s: open failed (%s)", ovs_rundir, strerror(errno));
+        return;
+    }
+
+    while ((de = readdir(dir)) != NULL) {
+        struct process_info pinfo;
+        char *key, *value;
+        char *file_name;
+        char *extension;
+        pid_t pid;
+
+#ifdef _DIRENT_HAVE_D_TYPE
+        if (de->d_type != DT_UNKNOWN && de->d_type != DT_REG) {
+            continue;
+        }
+#endif
+
+        extension = strrchr(de->d_name, '.');
+        if (!extension || strcmp(extension, ".pid")) {
+            continue;
+        }
+
+        file_name = xasprintf("%s/%s", ovs_rundir, de->d_name);
+        pid = read_pidfile(file_name);
+        free(file_name);
+        if (pid < 0 || kill(pid, 0)) {
+            continue;
+        }
+
+        key = xasprintf("process_%.*s",
+                        (int) (extension - de->d_name), de->d_name);
+        if (shash_find(stats, key)) {
+            free(key);
+            continue;
+        }
+
+        if (LINUX && get_process_info(pid, &pinfo)) {
+            value = xasprintf("%lu,%lu,%lld,%d,%lld,%lld",
+                              pinfo.vsz, pinfo.rss, pinfo.cputime,
+                              pinfo.crashes, pinfo.booted, pinfo.uptime);
+        } else {
+            value = xstrdup("");
+        }
+
+        shash_add_nocopy(stats, key, value);
+    }
+
+    closedir(dir);
+}
+
+static void
+get_filesys_stats(struct shash *stats OVS_UNUSED)
+{
+#if HAVE_SETMNTENT && HAVE_STATVFS
+    static const char file_name[] = "/etc/mtab";
+    struct mntent *me;
+    FILE *stream;
+    struct ds s;
+
+    stream = setmntent(file_name, "r");
+    if (!stream) {
+        VLOG_ERR_ONCE("%s: open failed (%s)", file_name, strerror(errno));
+        return;
+    }
+
+    ds_init(&s);
+    while ((me = getmntent(stream)) != NULL) {
+        unsigned long long int total, free;
+        struct statvfs vfs;
+        char *p;
+
+        /* Skip non-local and read-only filesystems. */
+        if (strncmp(me->mnt_fsname, "/dev", 4)
+            || !strstr(me->mnt_opts, "rw")) {
+            continue;
+        }
+
+        /* Given the mount point we can stat the file system. */
+        if (statvfs(me->mnt_dir, &vfs) && vfs.f_flag & ST_RDONLY) {
+            /* That's odd... */
+            continue;
+        }
+
+        /* Now format the data. */
+        if (s.length) {
+            ds_put_char(&s, ' ');
+        }
+        for (p = me->mnt_dir; *p != '\0'; p++) {
+            ds_put_char(&s, *p == ' ' || *p == ',' ? '_' : *p);
+        }
+        total = (unsigned long long int) vfs.f_frsize * vfs.f_blocks / 1024;
+        free = (unsigned long long int) vfs.f_frsize * vfs.f_bfree / 1024;
+        ds_put_format(&s, ",%llu,%llu", total, total - free);
+    }
+    endmntent(stream);
+
+    if (s.length) {
+        shash_add(stats, "file_systems", ds_steal_cstr(&s));
+    }
+    ds_destroy(&s);
+#endif  /* HAVE_SETMNTENT && HAVE_STATVFS */
+}
+
+void
+get_system_stats(struct shash *stats)
+{
+    get_cpu_cores(stats);
+    get_load_average(stats);
+    get_memory_stats(stats);
+    get_process_stats(stats);
+    get_filesys_stats(stats);
+}