quorum: Avoid bdrv_aio_writev() for rewrites
[qemu.git] / trace / control-target.c
1 /*
2 * Interface for configuring and controlling the state of tracing events.
3 *
4 * Copyright (C) 2014-2016 LluĂ­s 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 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
37 void 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
60 void 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
82 static 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
95 void 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 }