quorum: Avoid bdrv_aio_writev() for rewrites
[qemu.git] / trace / qmp.c
1 /*
2 * QMP commands for 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 "qmp-commands.h"
12 #include "trace/control.h"
13
14
15 static CPUState *get_cpu(bool has_vcpu, int vcpu, Error **errp)
16 {
17 if (has_vcpu) {
18 CPUState *cpu = qemu_get_cpu(vcpu);
19 if (cpu == NULL) {
20 error_setg(errp, "invalid vCPU index %u", vcpu);
21 }
22 return cpu;
23 } else {
24 return NULL;
25 }
26 }
27
28 static bool check_events(bool has_vcpu, bool ignore_unavailable, bool is_pattern,
29 const char *name, Error **errp)
30 {
31 if (!is_pattern) {
32 TraceEvent *ev = trace_event_name(name);
33
34 /* error for non-existing event */
35 if (ev == NULL) {
36 error_setg(errp, "unknown event \"%s\"", name);
37 return false;
38 }
39
40 /* error for non-vcpu event */
41 if (has_vcpu && !trace_event_is_vcpu(ev)) {
42 error_setg(errp, "event \"%s\" is not vCPU-specific", name);
43 return false;
44 }
45
46 /* error for unavailable event */
47 if (!ignore_unavailable && !trace_event_get_state_static(ev)) {
48 error_setg(errp, "event \"%s\" is disabled", name);
49 return false;
50 }
51
52 return true;
53 } else {
54 /* error for unavailable events */
55 TraceEventIter iter;
56 TraceEvent *ev;
57 trace_event_iter_init(&iter, name);
58 while ((ev = trace_event_iter_next(&iter)) != NULL) {
59 if (!ignore_unavailable && !trace_event_get_state_static(ev)) {
60 error_setg(errp, "event \"%s\" is disabled", trace_event_get_name(ev));
61 return false;
62 }
63 }
64 return true;
65 }
66 }
67
68 TraceEventInfoList *qmp_trace_event_get_state(const char *name,
69 bool has_vcpu, int64_t vcpu,
70 Error **errp)
71 {
72 Error *err = NULL;
73 TraceEventInfoList *events = NULL;
74 TraceEventIter iter;
75 TraceEvent *ev;
76 bool is_pattern = trace_event_is_pattern(name);
77 CPUState *cpu;
78
79 /* Check provided vcpu */
80 cpu = get_cpu(has_vcpu, vcpu, &err);
81 if (err) {
82 error_propagate(errp, err);
83 return NULL;
84 }
85
86 /* Check events */
87 if (!check_events(has_vcpu, true, is_pattern, name, errp)) {
88 return NULL;
89 }
90
91 /* Get states (all errors checked above) */
92 trace_event_iter_init(&iter, name);
93 while ((ev = trace_event_iter_next(&iter)) != NULL) {
94 TraceEventInfoList *elem;
95 bool is_vcpu = trace_event_is_vcpu(ev);
96 if (has_vcpu && !is_vcpu) {
97 continue;
98 }
99
100 elem = g_new(TraceEventInfoList, 1);
101 elem->value = g_new(TraceEventInfo, 1);
102 elem->value->vcpu = is_vcpu;
103 elem->value->name = g_strdup(trace_event_get_name(ev));
104
105 if (!trace_event_get_state_static(ev)) {
106 elem->value->state = TRACE_EVENT_STATE_UNAVAILABLE;
107 } else {
108 if (has_vcpu) {
109 if (is_vcpu) {
110 if (trace_event_get_vcpu_state_dynamic(cpu, ev)) {
111 elem->value->state = TRACE_EVENT_STATE_ENABLED;
112 } else {
113 elem->value->state = TRACE_EVENT_STATE_DISABLED;
114 }
115 }
116 /* else: already skipped above */
117 } else {
118 if (trace_event_get_state_dynamic(ev)) {
119 elem->value->state = TRACE_EVENT_STATE_ENABLED;
120 } else {
121 elem->value->state = TRACE_EVENT_STATE_DISABLED;
122 }
123 }
124 }
125 elem->next = events;
126 events = elem;
127 }
128
129 return events;
130 }
131
132 void qmp_trace_event_set_state(const char *name, bool enable,
133 bool has_ignore_unavailable, bool ignore_unavailable,
134 bool has_vcpu, int64_t vcpu,
135 Error **errp)
136 {
137 Error *err = NULL;
138 TraceEventIter iter;
139 TraceEvent *ev;
140 bool is_pattern = trace_event_is_pattern(name);
141 CPUState *cpu;
142
143 /* Check provided vcpu */
144 cpu = get_cpu(has_vcpu, vcpu, &err);
145 if (err) {
146 error_propagate(errp, err);
147 return;
148 }
149
150 /* Check events */
151 if (!check_events(has_vcpu, has_ignore_unavailable && ignore_unavailable,
152 is_pattern, name, errp)) {
153 return;
154 }
155
156 /* Apply changes (all errors checked above) */
157 trace_event_iter_init(&iter, name);
158 while ((ev = trace_event_iter_next(&iter)) != NULL) {
159 if (!trace_event_get_state_static(ev) ||
160 (has_vcpu && !trace_event_is_vcpu(ev))) {
161 continue;
162 }
163 if (has_vcpu) {
164 trace_event_set_vcpu_state_dynamic(cpu, ev, enable);
165 } else {
166 trace_event_set_state_dynamic(ev, enable);
167 }
168 }
169 }