1/*
2 * Interface for configuring and controlling the state of tracing events.
3 *
4 * Copyright (C) 2011-2016 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#ifndef TRACE__CONTROL_H
11#define TRACE__CONTROL_H
12
13#include "event-internal.h"
14
15typedef struct TraceEventIter {
16 size_t event;
17 size_t group;
18 const char *pattern;
19} TraceEventIter;
20
21
22/**
23 * trace_event_iter_init:
24 * @iter: the event iterator struct
25 * @pattern: optional pattern to filter events on name
26 *
27 * Initialize the event iterator struct @iter,
28 * optionally using @pattern to filter out events
29 * with non-matching names.
30 */
31void trace_event_iter_init(TraceEventIter *iter, const char *pattern);
32
33/**
34 * trace_event_iter_next:
35 * @iter: the event iterator struct
36 *
37 * Get the next event, if any. When this returns NULL,
38 * the iterator should no longer be used.
39 *
40 * Returns: the next event, or NULL if no more events exist
41 */
42TraceEvent *trace_event_iter_next(TraceEventIter *iter);
43
44
45/**
46 * trace_event_name:
47 * @id: Event name.
48 *
49 * Search an event by its name.
50 *
51 * Returns: pointer to #TraceEvent or NULL if not found.
52 */
53TraceEvent *trace_event_name(const char *name);
54
55/**
56 * trace_event_is_pattern:
57 *
58 * Whether the given string is an event name pattern.
59 */
60static bool trace_event_is_pattern(const char *str);
61
62
63/**
64 * trace_event_get_id:
65 *
66 * Get the identifier of an event.
67 */
68static uint32_t trace_event_get_id(TraceEvent *ev);
69
70/**
71 * trace_event_get_vcpu_id:
72 *
73 * Get the per-vCPU identifier of an event.
74 *
75 * Special value #TRACE_VCPU_EVENT_NONE means the event is not vCPU-specific
76 * (does not have the "vcpu" property).
77 */
78static uint32_t trace_event_get_vcpu_id(TraceEvent *ev);
79
80/**
81 * trace_event_is_vcpu:
82 *
83 * Whether this is a per-vCPU event.
84 */
85static bool trace_event_is_vcpu(TraceEvent *ev);
86
87/**
88 * trace_event_get_name:
89 *
90 * Get the name of an event.
91 */
92static const char * trace_event_get_name(TraceEvent *ev);
93
94/**
95 * trace_event_get_state:
96 * @id: Event identifier name.
97 *
98 * Get the tracing state of an event, both static and the QEMU dynamic state.
99 *
100 * If the event has the disabled property, the check will have no performance
101 * impact.
102 */
103#define trace_event_get_state(id) \
104 ((id ##_ENABLED) && trace_event_get_state_dynamic_by_id(id))
105
106/**
107 * trace_event_get_state_backends:
108 * @id: Event identifier name.
109 *
110 * Get the tracing state of an event, both static and dynamic state from all
111 * compiled-in backends.
112 *
113 * If the event has the disabled property, the check will have no performance
114 * impact.
115 *
116 * Returns: true if at least one backend has the event enabled and the event
117 * does not have the disabled property.
118 */
119#define trace_event_get_state_backends(id) \
120 ((id ##_ENABLED) && id ##_BACKEND_DSTATE())
121
122/**
123 * trace_event_get_state_static:
124 * @id: Event identifier.
125 *
126 * Get the static tracing state of an event.
127 *
128 * Use the define 'TRACE_${EVENT_NAME}_ENABLED' for compile-time checks (it will
129 * be set to 1 or 0 according to the presence of the disabled property).
130 */
131static bool trace_event_get_state_static(TraceEvent *ev);
132
133/**
134 * trace_event_get_state_dynamic:
135 *
136 * Get the dynamic tracing state of an event.
137 *
138 * If the event has the 'vcpu' property, gets the OR'ed state of all vCPUs.
139 */
140static bool trace_event_get_state_dynamic(TraceEvent *ev);
141
142/**
143 * trace_event_set_state_dynamic:
144 *
145 * Set the dynamic tracing state of an event.
146 *
147 * If the event has the 'vcpu' property, sets the state on all vCPUs.
148 *
149 * Pre-condition: trace_event_get_state_static(ev) == true
150 */
151void trace_event_set_state_dynamic(TraceEvent *ev, bool state);
152
153/**
154 * trace_event_set_vcpu_state_dynamic:
155 *
156 * Set the dynamic tracing state of an event for the given vCPU.
157 *
158 * Pre-condition: trace_event_get_vcpu_state_static(ev) == true
159 *
160 * Note: Changes for execution-time events with the 'tcg' property will not be
161 * propagated until the next TB is executed (iff executing in TCG mode).
162 */
163void trace_event_set_vcpu_state_dynamic(CPUState *vcpu,
164 TraceEvent *ev, bool state);
165
166
167
168/**
169 * trace_init_backends:
170 * @file: Name of trace output file; may be NULL.
171 * Corresponds to commandline option "--trace file=...".
172 *
173 * Initialize the tracing backend.
174 *
175 * Returns: Whether the backends could be successfully initialized.
176 */
177bool trace_init_backends(void);
178
179/**
180 * trace_init_file:
181 * @file: Name of trace output file; may be NULL.
182 * Corresponds to commandline option "--trace file=...".
183 *
184 * Record the name of the output file for the tracing backend.
185 * Exits if no selected backend does not support specifying the
186 * output file, and a non-NULL file was passed.
187 */
188void trace_init_file(const char *file);
189
190/**
191 * trace_init_vcpu:
192 * @vcpu: Added vCPU.
193 *
194 * Set initial dynamic event state for a hot-plugged vCPU.
195 */
196void trace_init_vcpu(CPUState *vcpu);
197
198/**
199 * trace_fini_vcpu:
200 * @vcpu: Removed vCPU.
201 *
202 * Disable dynamic event state for a hot-unplugged vCPU.
203 */
204void trace_fini_vcpu(CPUState *vcpu);
205
206/**
207 * trace_list_events:
208 *
209 * List all available events.
210 */
211void trace_list_events(void);
212
213/**
214 * trace_enable_events:
215 * @line_buf: A string with a glob pattern of events to be enabled or,
216 * if the string starts with '-', disabled.
217 *
218 * Enable or disable matching events.
219 */
220void trace_enable_events(const char *line_buf);
221
222/**
223 * Definition of QEMU options describing trace subsystem configuration
224 */
225extern QemuOptsList qemu_trace_opts;
226
227/**
228 * trace_opt_parse:
229 * @optarg: A string argument of --trace command line argument
230 *
231 * Initialize tracing subsystem.
232 *
233 * Returns the filename to save trace to. It must be freed with g_free().
234 */
235char *trace_opt_parse(const char *optarg);
236
237/**
238 * trace_get_vcpu_event_count:
239 *
240 * Return the number of known vcpu-specific events
241 */
242uint32_t trace_get_vcpu_event_count(void);
243
244
245#include "control-internal.h"
246
247#endif /* TRACE__CONTROL_H */
248