LXR qemu/trace/control-target.c

   1/*
   2 * Interface for configuring and controlling the state of tracing events.
   3 *
   4 * Copyright (C) 2014-2016 Lluís Vilanova <vilanova@ac.upc.edu>
   5 *
   6 * This work is licensed under the terms of the GNU GPL, version 2 or later.
   7 * See the COPYING file in the top-level directory.
   8 */
   9
  10#include "qemu/osdep.h"
  11#include "cpu.h"
  12#include "trace.h"
  13#include "trace/control.h"
  14#include "translate-all.h"
  15
  16
  17void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
  18{
  19    bool state_pre;
  20    assert(trace_event_get_state_static(ev));
  21    /*
  22     * We ignore the "vcpu" property here, since no vCPUs have been created
  23     * yet. Then dstate can only be 1 or 0.
  24     */
  25    state_pre = *ev->dstate;
  26    if (state_pre != state) {
  27        if (state) {
  28            trace_events_enabled_count++;
  29            *ev->dstate = 1;
  30        } else {
  31            trace_events_enabled_count--;
  32            *ev->dstate = 0;
  33        }
  34    }
  35}
  36
  37void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
  38{
  39    CPUState *vcpu;
  40    assert(trace_event_get_state_static(ev));
  41    if (trace_event_is_vcpu(ev)) {
  42        CPU_FOREACH(vcpu) {
  43            trace_event_set_vcpu_state_dynamic(vcpu, ev, state);
  44        }
  45    } else {
  46        /* Without the "vcpu" property, dstate can only be 1 or 0 */
  47        bool state_pre = *ev->dstate;
  48        if (state_pre != state) {
  49            if (state) {
  50                trace_events_enabled_count++;
  51                *ev->dstate = 1;
  52            } else {
  53                trace_events_enabled_count--;
  54                *ev->dstate = 0;
  55            }
  56        }
  57    }
  58}
  59
  60void trace_event_set_vcpu_state_dynamic(CPUState *vcpu,
  61                                        TraceEvent *ev, bool state)
  62{
  63    uint32_t vcpu_id;
  64    bool state_pre;
  65    assert(trace_event_get_state_static(ev));
  66    assert(trace_event_is_vcpu(ev));
  67    vcpu_id = trace_event_get_vcpu_id(ev);
  68    state_pre = test_bit(vcpu_id, vcpu->trace_dstate);
  69    if (state_pre != state) {
  70        if (state) {
  71            trace_events_enabled_count++;
  72            set_bit(vcpu_id, vcpu->trace_dstate);
  73            (*ev->dstate)++;
  74        } else {
  75            trace_events_enabled_count--;
  76            clear_bit(vcpu_id, vcpu->trace_dstate);
  77            (*ev->dstate)--;
  78        }
  79    }
  80}
  81
  82static bool adding_first_cpu(void)
  83{
  84    CPUState *cpu;
  85    size_t count = 0;
  86    CPU_FOREACH(cpu) {
  87        count++;
  88        if (count > 1) {
  89            return false;
  90        }
  91    }
  92    return true;
  93}
  94
  95void trace_init_vcpu(CPUState *vcpu)
  96{
  97    TraceEventIter iter;
  98    TraceEvent *ev;
  99    trace_event_iter_init(&iter, NULL);
 100    while ((ev = trace_event_iter_next(&iter)) != NULL) {
 101        if (trace_event_is_vcpu(ev) &&
 102            trace_event_get_state_static(ev) &&
 103            trace_event_get_state_dynamic(ev)) {
 104            if (adding_first_cpu()) {
 105                /* check preconditions */
 106                assert(*ev->dstate == 1);
 107                /* disable early-init state ... */
 108                *ev->dstate = 0;
 109                trace_events_enabled_count--;
 110                /* ... and properly re-enable */
 111                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
 112            } else {
 113                trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
 114            }
 115        }
 116    }
 117    trace_guest_cpu_enter(vcpu);
 118}
 119