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
  17 void trace_event_set_state_dynamic_init(TraceEvent *ev, bool state)
  18 {
  19     TraceEventID id = trace_event_get_id(ev);
  20     bool state_pre;
  21     assert(trace_event_get_state_static(ev));
  22     /*
  23      * We ignore the "vcpu" property here, since no vCPUs have been created
  24      * yet. Then dstate can only be 1 or 0.
  25      */
  26     state_pre = trace_events_dstate[id];
  27     if (state_pre != state) {
  28         if (state) {
  29             trace_events_enabled_count++;
  30             trace_events_dstate[id] = 1;
  31         } else {
  32             trace_events_enabled_count--;
  33             trace_events_dstate[id] = 0;
  34         }
  35     }
  36 }
  37
  38 void trace_event_set_state_dynamic(TraceEvent *ev, bool state)
  39 {
  40     CPUState *vcpu;
  41     assert(trace_event_get_state_static(ev));
  42     if (trace_event_is_vcpu(ev)) {
  43         CPU_FOREACH(vcpu) {
  44             trace_event_set_vcpu_state_dynamic(vcpu, ev, state);
  45         }
  46     } else {
  47         /* Without the "vcpu" property, dstate can only be 1 or 0 */
  48         TraceEventID id = trace_event_get_id(ev);
  49         bool state_pre = trace_events_dstate[id];
  50         if (state_pre != state) {
  51             if (state) {
  52                 trace_events_enabled_count++;
  53                 trace_events_dstate[id] = 1;
  54             } else {
  55                 trace_events_enabled_count--;
  56                 trace_events_dstate[id] = 0;
  57             }
  58         }
  59     }
  60 }
  61
  62 void trace_event_set_vcpu_state_dynamic(CPUState *vcpu,
  63                                         TraceEvent *ev, bool state)
  64 {
  65     TraceEventID id;
  66     TraceEventVCPUID vcpu_id;
  67     bool state_pre;
  68     assert(trace_event_get_state_static(ev));
  69     assert(trace_event_is_vcpu(ev));
  70     id = trace_event_get_id(ev);
  71     vcpu_id = trace_event_get_vcpu_id(ev);
  72     state_pre = test_bit(vcpu_id, vcpu->trace_dstate);
  73     if (state_pre != state) {
  74         if (state) {
  75             trace_events_enabled_count++;
  76             set_bit(vcpu_id, vcpu->trace_dstate);
  77             trace_events_dstate[id]++;
  78         } else {
  79             trace_events_enabled_count--;
  80             clear_bit(vcpu_id, vcpu->trace_dstate);
  81             trace_events_dstate[id]--;
  82         }
  83     }
  84 }
  85
  86 static bool adding_first_cpu(void)
  87 {
  88     CPUState *cpu;
  89     size_t count = 0;
  90     CPU_FOREACH(cpu) {
  91         count++;
  92         if (count > 1) {
  93             return false;
  94         }
  95     }
  96     return true;
  97 }
  98
  99 void trace_init_vcpu(CPUState *vcpu)
 100 {
 101     TraceEvent *ev = NULL;
 102
 103     while ((ev = trace_event_pattern("*", ev)) != NULL) {
 104         if (trace_event_is_vcpu(ev) &&
 105             trace_event_get_state_static(ev) &&
 106             trace_event_get_state_dynamic(ev)) {
 107             TraceEventID id = trace_event_get_id(ev);
 108             if (adding_first_cpu()) {
 109                 /* check preconditions */
 110                 assert(trace_events_dstate[id] == 1);
 111                 /* disable early-init state ... */
 112                 trace_events_dstate[id] = 0;
 113                 trace_events_enabled_count--;
 114                 /* ... and properly re-enable */
 115                 trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
 116             } else {
 117                 trace_event_set_vcpu_state_dynamic(vcpu, ev, true);
 118             }
 119         }
 120     }
 121
 122     trace_guest_cpu_enter(vcpu);
 123 }