summaryrefslogtreecommitdiff
path: root/trace/control-target.c
blob: 4e361019974703d089982028ae93100ece6e10d0 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
/*
 * Interface for configuring and controlling the state of tracing events.
 *
 * Copyright (C) 2014-2017 Lluís Vilanova <vilanova@ac.upc.edu>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 */

#include "qemu/osdep.h"
#include "cpu.h"
#include "trace-root.h"
#include "trace/control.h"
#include "translate-all.h"


void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
{
    bool state_pre;
    assert(trace_event_get_state_static(ev));
    /*
     * We ignore the "vcpu" property here, since no vCPUs have been created
     * yet. Then dstate can only be 1 or 0.
     */
    state_pre = *ev->dstate;
    if (state_pre != state) {
        if (state) {
            trace_events_enabled_count++;
            *ev->dstate = 1;
        } else {
            trace_events_enabled_count--;
            *ev->dstate = 0;
        }
    }
}

void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
{
    CPUState *vcpu;
    assert(trace_event_get_state_static(ev));
    if (trace_event_is_vcpu(ev) && likely(first_cpu != NULL)) {
        CPU_FOREACH(vcpu) {
            trace_event_set_vcpu_state_dynamic(vcpu, ev, state);
        }
    } else {
        /*
         * Without the "vcpu" property, dstate can only be 1 or 0. With it, we
         * haven't instantiated any vCPU yet, so we will set a global state
         * instead, and trace_init_vcpu will reconcile it afterwards.
         */
        bool state_pre = *ev->dstate;
        if (state_pre != state) {
            if (state) {
                trace_events_enabled_count++;
                *ev->dstate = 1;
            } else {
                trace_events_enabled_count--;
                *ev->dstate = 0;
            }
        }
    }
}

static void trace_event_synchronize_vcpu_state_dynamic(
    CPUState *vcpu, run_on_cpu_data ignored)
{
    bitmap_copy(vcpu->trace_dstate, vcpu->trace_dstate_delayed,
                CPU_TRACE_DSTATE_MAX_EVENTS);
    cpu_tb_jmp_cache_clear(vcpu);
}

void trace_event_set_vcpu_state_dynamic(CPUState *vcpu,
                                        TraceEvent *ev, bool state)
{
    uint32_t vcpu_id;
    bool state_pre;
    assert(trace_event_get_state_static(ev));
    assert(trace_event_is_vcpu(ev));
    vcpu_id = trace_event_get_vcpu_id(ev);
    state_pre = test_bit(vcpu_id, vcpu->trace_dstate);
    if (state_pre != state) {
        if (state) {
            trace_events_enabled_count++;
            set_bit(vcpu_id, vcpu->trace_dstate_delayed);
            (*ev->dstate)++;
        } else {
            trace_events_enabled_count--;
            clear_bit(vcpu_id, vcpu->trace_dstate_delayed);
            (*ev->dstate)--;
        }
        /*
         * Delay changes until next TB; we want all TBs to be built from a
         * single set of dstate values to ensure consistency of generated
         * tracing code.
         */
        async_run_on_cpu(vcpu, trace_event_synchronize_vcpu_state_dynamic,
                         RUN_ON_CPU_NULL);
    }
}

static bool adding_first_cpu1(void)
{
    CPUState *cpu;
    size_t count = 0;
    CPU_FOREACH(cpu) {
        count++;
        if (count > 1) {
            return false;
        }
    }
    return true;
}

static bool adding_first_cpu(void)
{
    bool res;
    cpu_list_lock();
    res = adding_first_cpu1();
    cpu_list_unlock();
    return res;
}

void trace_init_vcpu(CPUState *vcpu)
{
    TraceEventIter iter;
    TraceEvent *ev;
    trace_event_iter_init(&iter, NULL);
    while ((ev = trace_event_iter_next(&iter)) != NULL) {
        if (trace_event_is_vcpu(ev) &&
            trace_event_get_state_static(ev) &&
            trace_event_get_state_dynamic(ev)) {
            if (adding_first_cpu()) {
                /* check preconditions */
                assert(*ev->dstate == 1);
                /* disable early-init state ... */
                *ev->dstate = 0;
                trace_events_enabled_count--;
                /* ... and properly re-enable */
                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
            } else {
                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
            }
        }
    }
    trace_guest_cpu_enter(vcpu);
}