diff options
| -rw-r--r-- | tools/perf/Documentation/perf-record.txt | 6 | ||||
| -rw-r--r-- | tools/perf/builtin-record.c | 24 | ||||
| -rw-r--r-- | tools/perf/util/evlist.c | 234 | ||||
| -rw-r--r-- | tools/perf/util/evlist.h | 9 |
4 files changed, 269 insertions, 4 deletions
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 0228efc96686..b32a9c2726f9 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -433,8 +433,10 @@ if combined with -a or -C options. -D:: --delay=:: After starting the program, wait msecs before measuring (-1: start with events -disabled). This is useful to filter out the startup phase of the program, which -is often very different. +disabled), or enable events only for specified ranges of msecs (e.g. +-D 10-20,30-40 means wait 10 msecs, enable for 10 msecs, wait 10 msecs, enable +for 10 msecs, then stop). Note, delaying enabling of events is useful to filter +out the startup phase of the program, which is often very different. -I:: --intr-regs:: diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index f6204b8f8a06..df83dd436bdb 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -2502,6 +2502,10 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) } } + err = event_enable_timer__start(rec->evlist->eet); + if (err) + goto out_child; + trigger_ready(&auxtrace_snapshot_trigger); trigger_ready(&switch_output_trigger); perf_hooks__invoke_record_start(); @@ -2625,6 +2629,14 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) } } + err = event_enable_timer__process(rec->evlist->eet); + if (err < 0) + goto out_child; + if (err) { + err = 0; + done = 1; + } + /* * When perf is starting the traced process, at the end events * die with the process and we wait for that. Thus no need to @@ -2846,6 +2858,12 @@ static int perf_record_config(const char *var, const char *value, void *cb) return 0; } +static int record__parse_event_enable_time(const struct option *opt, const char *str, int unset) +{ + struct record *rec = (struct record *)opt->value; + + return evlist__parse_event_enable_time(rec->evlist, &rec->opts, str, unset); +} static int record__parse_affinity(const struct option *opt, const char *str, int unset) { @@ -3307,8 +3325,10 @@ static struct option __record_options[] = { OPT_CALLBACK('G', "cgroup", &record.evlist, "name", "monitor event in cgroup name only", parse_cgroups), - OPT_INTEGER('D', "delay", &record.opts.initial_delay, - "ms to wait before starting measurement after program start (-1: start with events disabled)"), + OPT_CALLBACK('D', "delay", &record, "ms", + "ms to wait before starting measurement after program start (-1: start with events disabled), " + "or ranges of time to enable events e.g. '-D 10-20,30-40'", + record__parse_event_enable_time), OPT_BOOLEAN(0, "kcore", &record.opts.kcore, "copy /proc/kcore"), OPT_STRING('u', "uid", &record.opts.target.uid_str, "user", "user to profile"), diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 3cfe730c12b8..fcfe5bcc0bcf 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -15,6 +15,7 @@ #include "target.h" #include "evlist.h" #include "evsel.h" +#include "record.h" #include "debug.h" #include "units.h" #include "bpf_counter.h" @@ -40,12 +41,14 @@ #include <sys/ioctl.h> #include <sys/mman.h> #include <sys/prctl.h> +#include <sys/timerfd.h> #include <linux/bitops.h> #include <linux/hash.h> #include <linux/log2.h> #include <linux/err.h> #include <linux/string.h> +#include <linux/time64.h> #include <linux/zalloc.h> #include <perf/evlist.h> #include <perf/evsel.h> @@ -147,6 +150,7 @@ static void evlist__purge(struct evlist *evlist) void evlist__exit(struct evlist *evlist) { + event_enable_timer__exit(&evlist->eet); zfree(&evlist->mmap); zfree(&evlist->overwrite_mmap); perf_evlist__exit(&evlist->core); @@ -2167,6 +2171,236 @@ int evlist__ctlfd_process(struct evlist *evlist, enum evlist_ctl_cmd *cmd) return err; } +/** + * struct event_enable_time - perf record -D/--delay single time range. + * @start: start of time range to enable events in milliseconds + * @end: end of time range to enable events in milliseconds + * + * N.B. this structure is also accessed as an array of int. + */ +struct event_enable_time { + int start; + int end; +}; + +static int parse_event_enable_time(const char *str, struct event_enable_time *range, bool first) +{ + const char *fmt = first ? "%u - %u %n" : " , %u - %u %n"; + int ret, start, end, n; + + ret = sscanf(str, fmt, &start, &end, &n); + if (ret != 2 || end <= start) + return -EINVAL; + if (range) { + range->start = start; + range->end = end; + } + return n; +} + +static ssize_t parse_event_enable_times(const char *str, struct event_enable_time *range) +{ + int incr = !!range; + bool first = true; + ssize_t ret, cnt; + + for (cnt = 0; *str; cnt++) { + ret = parse_event_enable_time(str, range, first); + if (ret < 0) + return ret; + /* Check no overlap */ + if (!first && range && range->start <= range[-1].end) + return -EINVAL; + str += ret; + range += incr; + first = false; + } + return cnt; +} + +/** + * struct event_enable_timer - control structure for perf record -D/--delay. + * @evlist: event list + * @times: time ranges that events are enabled (N.B. this is also accessed as an + * array of int) + * @times_cnt: number of time ranges + * @timerfd: timer file descriptor + * @pollfd_pos: position in @evlist array of file descriptors to poll (fdarray) + * @times_step: current position in (int *)@times)[], + * refer event_enable_timer__process() + * + * Note, this structure is only used when there are time ranges, not when there + * is only an initial delay. + */ +struct event_enable_timer { + struct evlist *evlist; + struct event_enable_time *times; + size_t times_cnt; + int timerfd; + int pollfd_pos; + size_t times_step; +}; + +static int str_to_delay(const char *str) +{ + char *endptr; + long d; + + d = strtol(str, &endptr, 10); + if (*endptr || d > INT_MAX || d < -1) + return 0; + return d; +} + +int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts, + const char *str, int unset) +{ + enum fdarray_flags flags = fdarray_flag__nonfilterable | fdarray_flag__non_perf_event; + struct event_enable_timer *eet; + ssize_t times_cnt; + ssize_t ret; + int err; + + if (unset) + return 0; + + opts->initial_delay = str_to_delay(str); + if (opts->initial_delay) + return 0; + + ret = parse_event_enable_times(str, NULL); + if (ret < 0) + return ret; + + times_cnt = ret; + if (times_cnt == 0) + return -EINVAL; + + eet = zalloc(sizeof(*eet)); + if (!eet) + return -ENOMEM; + + eet->times = calloc(times_cnt, sizeof(*eet->times)); + if (!eet->times) { + err = -ENOMEM; + goto free_eet; + } + + if (parse_event_enable_times(str, eet->times) != times_cnt) { + err = -EINVAL; + goto free_eet_times; + } + + eet->times_cnt = times_cnt; + + eet->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC); + if (eet->timerfd == -1) { + err = -errno; + pr_err("timerfd_create failed: %s\n", strerror(errno)); + goto free_eet_times; + } + + eet->pollfd_pos = perf_evlist__add_pollfd(&evlist->core, eet->timerfd, NULL, POLLIN, flags); + if (eet->pollfd_pos < 0) { + err = eet->pollfd_pos; + goto close_timerfd; + } + + eet->evlist = evlist; + evlist->eet = eet; + opts->initial_delay = eet->times[0].start; + + return 0; + +close_timerfd: + close(eet->timerfd); +free_eet_times: + free(eet->times); +free_eet: + free(eet); + return err; +} + +static int event_enable_timer__set_timer(struct event_enable_timer *eet, int ms) +{ + struct itimerspec its = { + .it_value.tv_sec = ms / MSEC_PER_SEC, + .it_value.tv_nsec = (ms % MSEC_PER_SEC) * NSEC_PER_MSEC, + }; + int err = 0; + + if (timerfd_settime(eet->timerfd, 0, &its, NULL) < 0) { + err = -errno; + pr_err("timerfd_settime failed: %s\n", strerror(errno)); + } + return err; +} + +int event_enable_timer__start(struct event_enable_timer *eet) +{ + int ms; + + if (!eet) + return 0; + + ms = eet->times[0].end - eet->times[0].start; + eet->times_step = 1; + + return event_enable_timer__set_timer(eet, ms); +} + +int event_enable_timer__process(struct event_enable_timer *eet) +{ + struct pollfd *entries; + short revents; + + if (!eet) + return 0; + + entries = eet->evlist->core.pollfd.entries; + revents = entries[eet->pollfd_pos].revents; + entries[eet->pollfd_pos].revents = 0; + + if (revents & POLLIN) { + size_t step = eet->times_step; + size_t pos = step / 2; + + if (step & 1) { + evlist__disable_non_dummy(eet->evlist); + pr_info(EVLIST_DISABLED_MSG); + if (pos >= eet->times_cnt - 1) { + /* Disarm timer */ + event_enable_timer__set_timer(eet, 0); + return 1; /* Stop */ + } + } else { + evlist__enable_non_dummy(eet->evlist); + pr_info(EVLIST_ENABLED_MSG); + } + + step += 1; + pos = step / 2; + + if (pos < eet->times_cnt) { + int *times = (int *)eet->times; /* Accessing 'times' as array of int */ + int ms = times[step] - times[step - 1]; + + eet->times_step = step; + return event_enable_timer__set_timer(eet, ms); + } + } + + return 0; +} + +void event_enable_timer__exit(struct event_enable_timer **ep) +{ + if (!ep || !*ep) + return; + free((*ep)->times); + zfree(ep); +} + struct evsel *evlist__find_evsel(struct evlist *evlist, int idx) { struct evsel *evsel; diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index 3a8474406738..9d967fe3953a 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -48,6 +48,8 @@ enum bkw_mmap_state { BKW_MMAP_EMPTY, }; +struct event_enable_timer; + struct evlist { struct perf_evlist core; bool enabled; @@ -79,6 +81,7 @@ struct evlist { int ack; /* ack file descriptor for control commands */ int pos; /* index at evlist core object to check signals */ } ctl_fd; + struct event_enable_timer *eet; }; struct evsel_str_handler { @@ -426,6 +429,12 @@ int evlist__ctlfd_ack(struct evlist *evlist); #define EVLIST_ENABLED_MSG "Events enabled\n" #define EVLIST_DISABLED_MSG "Events disabled\n" +int evlist__parse_event_enable_time(struct evlist *evlist, struct record_opts *opts, + const char *str, int unset); +int event_enable_timer__start(struct event_enable_timer *eet); +void event_enable_timer__exit(struct event_enable_timer **ep); +int event_enable_timer__process(struct event_enable_timer *eet); + struct evsel *evlist__find_evsel(struct evlist *evlist, int idx); int evlist__scnprintf_evsels(struct evlist *evlist, size_t size, char *bf); |