4 #include "parse-events.h"
9 typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
11 static int perf_do_probe_api(setup_probe_fn_t fn, int cpu, const char *str)
13 struct perf_evlist *evlist;
14 struct perf_evsel *evsel;
15 unsigned long flags = perf_event_open_cloexec_flag();
16 int err = -EAGAIN, fd;
17 static pid_t pid = -1;
19 evlist = perf_evlist__new();
23 if (parse_events(evlist, str, NULL))
26 evsel = perf_evlist__first(evlist);
29 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
31 if (pid == -1 && errno == EACCES) {
43 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
53 perf_evlist__delete(evlist);
57 static bool perf_probe_api(setup_probe_fn_t fn)
59 const char *try[] = {"cycles:u", "instructions:u", "cpu-clock:u", NULL};
63 cpus = cpu_map__new(NULL);
70 ret = perf_do_probe_api(fn, cpu, try[i++]);
73 } while (ret == -EAGAIN && try[i]);
78 static void perf_probe_sample_identifier(struct perf_evsel *evsel)
80 evsel->attr.sample_type |= PERF_SAMPLE_IDENTIFIER;
83 static void perf_probe_comm_exec(struct perf_evsel *evsel)
85 evsel->attr.comm_exec = 1;
88 static void perf_probe_context_switch(struct perf_evsel *evsel)
90 evsel->attr.context_switch = 1;
93 bool perf_can_sample_identifier(void)
95 return perf_probe_api(perf_probe_sample_identifier);
98 static bool perf_can_comm_exec(void)
100 return perf_probe_api(perf_probe_comm_exec);
103 bool perf_can_record_switch_events(void)
105 return perf_probe_api(perf_probe_context_switch);
108 bool perf_can_record_cpu_wide(void)
110 struct perf_event_attr attr = {
111 .type = PERF_TYPE_SOFTWARE,
112 .config = PERF_COUNT_SW_CPU_CLOCK,
115 struct cpu_map *cpus;
118 cpus = cpu_map__new(NULL);
124 fd = sys_perf_event_open(&attr, -1, cpu, -1, 0);
132 void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts)
134 struct perf_evsel *evsel;
135 bool use_sample_identifier = false;
139 * Set the evsel leader links before we configure attributes,
140 * since some might depend on this info.
143 perf_evlist__set_leader(evlist);
145 if (evlist->cpus->map[0] < 0)
146 opts->no_inherit = true;
148 use_comm_exec = perf_can_comm_exec();
150 evlist__for_each(evlist, evsel) {
151 perf_evsel__config(evsel, opts);
152 if (evsel->tracking && use_comm_exec)
153 evsel->attr.comm_exec = 1;
156 if (opts->full_auxtrace) {
158 * Need to be able to synthesize and parse selected events with
159 * arbitrary sample types, which requires always being able to
162 use_sample_identifier = perf_can_sample_identifier();
163 evlist__for_each(evlist, evsel)
164 perf_evsel__set_sample_id(evsel, use_sample_identifier);
165 } else if (evlist->nr_entries > 1) {
166 struct perf_evsel *first = perf_evlist__first(evlist);
168 evlist__for_each(evlist, evsel) {
169 if (evsel->attr.sample_type == first->attr.sample_type)
171 use_sample_identifier = perf_can_sample_identifier();
174 evlist__for_each(evlist, evsel)
175 perf_evsel__set_sample_id(evsel, use_sample_identifier);
178 perf_evlist__set_id_pos(evlist);
181 static int get_max_rate(unsigned int *rate)
183 return sysctl__read_int("kernel/perf_event_max_sample_rate", (int *)rate);
186 static int record_opts__config_freq(struct record_opts *opts)
188 bool user_freq = opts->user_freq != UINT_MAX;
189 unsigned int max_rate;
191 if (opts->user_interval != ULLONG_MAX)
192 opts->default_interval = opts->user_interval;
194 opts->freq = opts->user_freq;
197 * User specified count overrides default frequency.
199 if (opts->default_interval)
201 else if (opts->freq) {
202 opts->default_interval = opts->freq;
204 pr_err("frequency and count are zero, aborting\n");
208 if (get_max_rate(&max_rate))
212 * User specified frequency is over current maximum.
214 if (user_freq && (max_rate < opts->freq)) {
215 pr_err("Maximum frequency rate (%u) reached.\n"
216 "Please use -F freq option with lower value or consider\n"
217 "tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
223 * Default frequency is over current maximum.
225 if (max_rate < opts->freq) {
226 pr_warning("Lowering default frequency rate to %u.\n"
227 "Please consider tweaking "
228 "/proc/sys/kernel/perf_event_max_sample_rate.\n",
230 opts->freq = max_rate;
236 int record_opts__config(struct record_opts *opts)
238 return record_opts__config_freq(opts);
241 bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
243 struct perf_evlist *temp_evlist;
244 struct perf_evsel *evsel;
249 temp_evlist = perf_evlist__new();
253 err = parse_events(temp_evlist, str, NULL);
257 evsel = perf_evlist__last(temp_evlist);
259 if (!evlist || cpu_map__empty(evlist->cpus)) {
260 struct cpu_map *cpus = cpu_map__new(NULL);
262 cpu = cpus ? cpus->map[0] : 0;
265 cpu = evlist->cpus->map[0];
269 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1,
270 perf_event_open_cloexec_flag());
272 if (pid == -1 && errno == EACCES) {
284 perf_evlist__delete(temp_evlist);