vmsvga: don't process more than 1024 fifo commands at once
[qemu.git] / trace / control.h
1 /*
2 * Interface for configuring and controlling the state of tracing events.
3 *
4 * Copyright (C) 2011-2016 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 #ifndef TRACE__CONTROL_H
11 #define TRACE__CONTROL_H
12
13 #include "qemu-common.h"
14 #include "trace/generated-events.h"
15
16
17 /**
18 * TraceEventID:
19 *
20 * Unique tracing event identifier.
21 *
22 * These are named as 'TRACE_${EVENT_NAME}'.
23 *
24 * See also: "trace/generated-events.h"
25 */
26 enum TraceEventID;
27
28 /**
29 * trace_event_id:
30 * @id: Event identifier.
31 *
32 * Get an event by its identifier.
33 *
34 * This routine has a constant cost, as opposed to trace_event_name and
35 * trace_event_pattern.
36 *
37 * Pre-conditions: The identifier is valid.
38 *
39 * Returns: pointer to #TraceEvent.
40 *
41 */
42 static TraceEvent *trace_event_id(TraceEventID id);
43
44 /**
45 * trace_event_name:
46 * @id: Event name.
47 *
48 * Search an event by its name.
49 *
50 * Returns: pointer to #TraceEvent or NULL if not found.
51 */
52 TraceEvent *trace_event_name(const char *name);
53
54 /**
55 * trace_event_pattern:
56 * @pat: Event name pattern.
57 * @ev: Event to start searching from (not included).
58 *
59 * Get all events with a given name pattern.
60 *
61 * Returns: pointer to #TraceEvent or NULL if not found.
62 */
63 TraceEvent *trace_event_pattern(const char *pat, TraceEvent *ev);
64
65 /**
66 * trace_event_is_pattern:
67 *
68 * Whether the given string is an event name pattern.
69 */
70 static bool trace_event_is_pattern(const char *str);
71
72 /**
73 * trace_event_count:
74 *
75 * Return the number of events.
76 */
77 static TraceEventID trace_event_count(void);
78
79
80
81 /**
82 * trace_event_get_id:
83 *
84 * Get the identifier of an event.
85 */
86 static TraceEventID trace_event_get_id(TraceEvent *ev);
87
88 /**
89 * trace_event_get_name:
90 *
91 * Get the name of an event.
92 */
93 static const char * trace_event_get_name(TraceEvent *ev);
94
95 /**
96 * trace_event_get_state:
97 * @id: Event identifier.
98 *
99 * Get the tracing state of an event (both static and dynamic).
100 *
101 * If the event has the disabled property, the check will have no performance
102 * impact.
103 *
104 * As a down side, you must always use an immediate #TraceEventID value.
105 */
106 #define trace_event_get_state(id) \
107 ((id ##_ENABLED) && trace_event_get_state_dynamic_by_id(id))
108
109 /**
110 * trace_event_get_state_static:
111 * @id: Event identifier.
112 *
113 * Get the static tracing state of an event.
114 *
115 * Use the define 'TRACE_${EVENT_NAME}_ENABLED' for compile-time checks (it will
116 * be set to 1 or 0 according to the presence of the disabled property).
117 */
118 static bool trace_event_get_state_static(TraceEvent *ev);
119
120 /**
121 * trace_event_get_state_dynamic:
122 *
123 * Get the dynamic tracing state of an event.
124 */
125 static bool trace_event_get_state_dynamic(TraceEvent *ev);
126
127 /**
128 * trace_event_set_state:
129 *
130 * Set the tracing state of an event (only if possible).
131 */
132 #define trace_event_set_state(id, state) \
133 do { \
134 if ((id ##_ENABLED)) { \
135 TraceEvent *_e = trace_event_id(id); \
136 trace_event_set_state_dynamic(_e, state); \
137 } \
138 } while (0)
139
140 /**
141 * trace_event_set_state_dynamic:
142 *
143 * Set the dynamic tracing state of an event.
144 *
145 * Pre-condition: trace_event_get_state_static(ev) == true
146 */
147 static void trace_event_set_state_dynamic(TraceEvent *ev, bool state);
148
149
150
151 /**
152 * trace_init_backends:
153 * @file: Name of trace output file; may be NULL.
154 * Corresponds to commandline option "-trace file=...".
155 *
156 * Initialize the tracing backend.
157 *
158 * Returns: Whether the backends could be successfully initialized.
159 */
160 bool trace_init_backends(void);
161
162 /**
163 * trace_init_events:
164 * @events: Name of file with events to be enabled at startup; may be NULL.
165 * Corresponds to commandline option "-trace events=...".
166 *
167 * Read the list of enabled tracing events.
168 *
169 * Returns: Whether the backends could be successfully initialized.
170 */
171 void trace_init_events(const char *file);
172
173 /**
174 * trace_init_file:
175 * @file: Name of trace output file; may be NULL.
176 * Corresponds to commandline option "-trace file=...".
177 *
178 * Record the name of the output file for the tracing backend.
179 * Exits if no selected backend does not support specifying the
180 * output file, and a non-NULL file was passed.
181 */
182 void trace_init_file(const char *file);
183
184 /**
185 * trace_list_events:
186 *
187 * List all available events.
188 */
189 void trace_list_events(void);
190
191 /**
192 * trace_enable_events:
193 * @line_buf: A string with a glob pattern of events to be enabled or,
194 * if the string starts with '-', disabled.
195 *
196 * Enable or disable matching events.
197 */
198 void trace_enable_events(const char *line_buf);
199
200
201 #include "trace/control-internal.h"
202
203 #endif /* TRACE__CONTROL_H */