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 15 typedef struct TraceEventIter { 16 /* iter state */ 17 size_t event; 18 size_t group; 19 /* filter conditions */ 20 size_t group_id; 21 const char *pattern; 22 } TraceEventIter; 23 24 25 /** 26 * trace_event_iter_init_all: 27 * @iter: the event iterator struct 28 * 29 * Initialize the event iterator struct @iter, 30 * for all events. 31 */ 32 void trace_event_iter_init_all(TraceEventIter *iter); 33 34 /** 35 * trace_event_iter_init_pattern: 36 * @iter: the event iterator struct 37 * @pattern: pattern to filter events on name 38 * 39 * Initialize the event iterator struct @iter, 40 * using @pattern to filter out events 41 * with non-matching names. 42 */ 43 void trace_event_iter_init_pattern(TraceEventIter *iter, const char *pattern); 44 45 /** 46 * trace_event_iter_init_group: 47 * @iter: the event iterator struct 48 * @group_id: group_id to filter events by group. 49 * 50 * Initialize the event iterator struct @iter, 51 * using @group_id to filter for events in the group. 52 */ 53 void trace_event_iter_init_group(TraceEventIter *iter, size_t group_id); 54 55 /** 56 * trace_event_iter_next: 57 * @iter: the event iterator struct 58 * 59 * Get the next event, if any. When this returns NULL, 60 * the iterator should no longer be used. 61 * 62 * Returns: the next event, or NULL if no more events exist 63 */ 64 TraceEvent *trace_event_iter_next(TraceEventIter *iter); 65 66 67 /** 68 * trace_event_name: 69 * @id: Event name. 70 * 71 * Search an event by its name. 72 * 73 * Returns: pointer to #TraceEvent or NULL if not found. 74 */ 75 TraceEvent *trace_event_name(const char *name); 76 77 /** 78 * trace_event_is_pattern: 79 * 80 * Whether the given string is an event name pattern. 81 */ 82 static bool trace_event_is_pattern(const char *str); 83 84 85 /** 86 * trace_event_get_id: 87 * 88 * Get the identifier of an event. 89 */ 90 static uint32_t trace_event_get_id(TraceEvent *ev); 91 92 /** 93 * trace_event_get_name: 94 * 95 * Get the name of an event. 96 */ 97 static const char * trace_event_get_name(TraceEvent *ev); 98 99 /** 100 * trace_event_get_state: 101 * @id: Event identifier name. 102 * 103 * Get the tracing state of an event, both static and the QEMU dynamic state. 104 * 105 * If the event has the disabled property, the check will have no performance 106 * impact. 107 */ 108 #define trace_event_get_state(id) \ 109 ((id ##_ENABLED) && trace_event_get_state_dynamic_by_id(id)) 110 111 /** 112 * trace_event_get_state_backends: 113 * @id: Event identifier name. 114 * 115 * Get the tracing state of an event, both static and dynamic state from all 116 * compiled-in backends. 117 * 118 * If the event has the disabled property, the check will have no performance 119 * impact. 120 * 121 * Returns: true if at least one backend has the event enabled and the event 122 * does not have the disabled property. 123 */ 124 #define trace_event_get_state_backends(id) \ 125 ((id ##_ENABLED) && id ##_BACKEND_DSTATE()) 126 127 /** 128 * trace_event_get_state_static: 129 * @id: Event identifier. 130 * 131 * Get the static tracing state of an event. 132 * 133 * Use the define 'TRACE_${EVENT_NAME}_ENABLED' for compile-time checks (it will 134 * be set to 1 or 0 according to the presence of the disabled property). 135 */ 136 static bool trace_event_get_state_static(TraceEvent *ev); 137 138 /** 139 * trace_event_get_state_dynamic: 140 * 141 * Get the dynamic tracing state of an event. 142 * 143 * If the event has the 'vcpu' property, gets the OR'ed state of all vCPUs. 144 */ 145 static bool trace_event_get_state_dynamic(TraceEvent *ev); 146 147 /** 148 * trace_event_set_state_dynamic: 149 * 150 * Set the dynamic tracing state of an event. 151 * 152 * If the event has the 'vcpu' property, sets the state on all vCPUs. 153 * 154 * Pre-condition: trace_event_get_state_static(ev) == true 155 */ 156 void trace_event_set_state_dynamic(TraceEvent *ev, bool state); 157 158 /** 159 * trace_init_backends: 160 * 161 * Initialize the tracing backend. 162 * 163 * Returns: Whether the backends could be successfully initialized. 164 */ 165 bool trace_init_backends(void); 166 167 /** 168 * trace_init_file: 169 * 170 * Record the name of the output file for the tracing backend. 171 * Exits if no selected backend does not support specifying the 172 * output file, and a file was specified with "-trace file=...". 173 */ 174 void trace_init_file(void); 175 176 /** 177 * trace_list_events: 178 * @f: Where to send output. 179 * 180 * List all available events. 181 */ 182 void trace_list_events(FILE *f); 183 184 /** 185 * trace_enable_events: 186 * @line_buf: A string with a glob pattern of events to be enabled or, 187 * if the string starts with '-', disabled. 188 * 189 * Enable or disable matching events. 190 */ 191 void trace_enable_events(const char *line_buf); 192 193 /** 194 * Definition of QEMU options describing trace subsystem configuration 195 */ 196 extern QemuOptsList qemu_trace_opts; 197 198 /** 199 * trace_opt_parse: 200 * @optstr: A string argument of --trace command line argument 201 * 202 * Initialize tracing subsystem. 203 */ 204 void trace_opt_parse(const char *optstr); 205 206 /** 207 * trace_get_vcpu_event_count: 208 * 209 * Return the number of known vcpu-specific events 210 */ 211 uint32_t trace_get_vcpu_event_count(void); 212 213 214 #include "control-internal.h" 215 216 #endif /* TRACE__CONTROL_H */ 217