4 #include "parse-events.h"
10 typedef void (*setup_probe_fn_t)(struct perf_evsel *evsel);
12 static int perf_do_probe_api(setup_probe_fn_t fn, int cpu, const char *str)
14 struct perf_evlist *evlist;
15 struct perf_evsel *evsel;
16 unsigned long flags = perf_event_open_cloexec_flag();
17 int err = -EAGAIN, fd;
18 static pid_t pid = -1;
20 evlist = perf_evlist__new();
24 if (parse_events(evlist, str, NULL))
27 evsel = perf_evlist__first(evlist);
30 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
32 if (pid == -1 && errno == EACCES) {
44 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1, flags);
54 perf_evlist__delete(evlist);
58 static bool perf_probe_api(setup_probe_fn_t fn)
60 const char *try[] = {"cycles:u", "instructions:u", "cpu-clock:u", NULL};
64 cpus = cpu_map__new(NULL);
71 ret = perf_do_probe_api(fn, cpu, try[i++]);
74 } while (ret == -EAGAIN && try[i]);
79 static void perf_probe_sample_identifier(struct perf_evsel *evsel)
81 evsel->attr.sample_type |= PERF_SAMPLE_IDENTIFIER;
84 static void perf_probe_comm_exec(struct perf_evsel *evsel)
86 evsel->attr.comm_exec = 1;
89 static void perf_probe_context_switch(struct perf_evsel *evsel)
91 evsel->attr.context_switch = 1;
94 bool perf_can_sample_identifier(void)
96 return perf_probe_api(perf_probe_sample_identifier);
99 static bool perf_can_comm_exec(void)
101 return perf_probe_api(perf_probe_comm_exec);
104 bool perf_can_record_switch_events(void)
106 return perf_probe_api(perf_probe_context_switch);
109 bool perf_can_record_cpu_wide(void)
111 struct perf_event_attr attr = {
112 .type = PERF_TYPE_SOFTWARE,
113 .config = PERF_COUNT_SW_CPU_CLOCK,
116 struct cpu_map *cpus;
119 cpus = cpu_map__new(NULL);
125 fd = sys_perf_event_open(&attr, -1, cpu, -1, 0);
133 void perf_evlist__config(struct perf_evlist *evlist, struct record_opts *opts,
134 struct callchain_param *callchain)
136 struct perf_evsel *evsel;
137 bool use_sample_identifier = false;
141 * Set the evsel leader links before we configure attributes,
142 * since some might depend on this info.
145 perf_evlist__set_leader(evlist);
147 if (evlist->cpus->map[0] < 0)
148 opts->no_inherit = true;
150 use_comm_exec = perf_can_comm_exec();
152 evlist__for_each_entry(evlist, evsel) {
153 perf_evsel__config(evsel, opts, callchain);
154 if (evsel->tracking && use_comm_exec)
155 evsel->attr.comm_exec = 1;
158 if (opts->full_auxtrace) {
160 * Need to be able to synthesize and parse selected events with
161 * arbitrary sample types, which requires always being able to
164 use_sample_identifier = perf_can_sample_identifier();
165 evlist__for_each_entry(evlist, evsel)
166 perf_evsel__set_sample_id(evsel, use_sample_identifier);
167 } else if (evlist->nr_entries > 1) {
168 struct perf_evsel *first = perf_evlist__first(evlist);
170 evlist__for_each_entry(evlist, evsel) {
171 if (evsel->attr.sample_type == first->attr.sample_type)
173 use_sample_identifier = perf_can_sample_identifier();
176 evlist__for_each_entry(evlist, evsel)
177 perf_evsel__set_sample_id(evsel, use_sample_identifier);
180 perf_evlist__set_id_pos(evlist);
183 static int get_max_rate(unsigned int *rate)
185 return sysctl__read_int("kernel/perf_event_max_sample_rate", (int *)rate);
188 static int record_opts__config_freq(struct record_opts *opts)
190 bool user_freq = opts->user_freq != UINT_MAX;
191 unsigned int max_rate;
193 if (opts->user_interval != ULLONG_MAX)
194 opts->default_interval = opts->user_interval;
196 opts->freq = opts->user_freq;
199 * User specified count overrides default frequency.
201 if (opts->default_interval)
203 else if (opts->freq) {
204 opts->default_interval = opts->freq;
206 pr_err("frequency and count are zero, aborting\n");
210 if (get_max_rate(&max_rate))
214 * User specified frequency is over current maximum.
216 if (user_freq && (max_rate < opts->freq)) {
217 pr_err("Maximum frequency rate (%u) reached.\n"
218 "Please use -F freq option with lower value or consider\n"
219 "tweaking /proc/sys/kernel/perf_event_max_sample_rate.\n",
225 * Default frequency is over current maximum.
227 if (max_rate < opts->freq) {
228 pr_warning("Lowering default frequency rate to %u.\n"
229 "Please consider tweaking "
230 "/proc/sys/kernel/perf_event_max_sample_rate.\n",
232 opts->freq = max_rate;
238 int record_opts__config(struct record_opts *opts)
240 return record_opts__config_freq(opts);
243 bool perf_evlist__can_select_event(struct perf_evlist *evlist, const char *str)
245 struct perf_evlist *temp_evlist;
246 struct perf_evsel *evsel;
251 temp_evlist = perf_evlist__new();
255 err = parse_events(temp_evlist, str, NULL);
259 evsel = perf_evlist__last(temp_evlist);
261 if (!evlist || cpu_map__empty(evlist->cpus)) {
262 struct cpu_map *cpus = cpu_map__new(NULL);
264 cpu = cpus ? cpus->map[0] : 0;
267 cpu = evlist->cpus->map[0];
271 fd = sys_perf_event_open(&evsel->attr, pid, cpu, -1,
272 perf_event_open_cloexec_flag());
274 if (pid == -1 && errno == EACCES) {
286 perf_evlist__delete(temp_evlist);