From 67ccdecd09cac818146b1e153ff901cb67570012 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Thu, 3 Dec 2015 10:06:44 +0100 Subject: [PATCH] perf stat: Create events as disabled Currently we have 2 kinds of stat counters based on when the event is enabled: 1) tracee command events, which are enable once the tracee executes exec syscall (enable_on_exec bit) 2) all other events which get alive within the perf_event_open syscall And 2) case could raise a problem in case we want additional filter to be attached for event. In this case we want the event to be enabled after it's configured with filter. Changing the behaviour of 2) events, so they all are created as disabled (disabled bit). Adding extra enable call to make them alive once they finish setup. Signed-off-by: Jiri Olsa Cc: Adrian Hunter Cc: David Ahern Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1449133606-14429-6-git-send-email-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-stat.c | 25 +++++++++++++++++++------ 1 file changed, 19 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index 8ca40deaa728..2e70610649a1 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -168,11 +168,18 @@ static int create_perf_stat_counter(struct perf_evsel *evsel) attr->sample_period = 0; attr->sample_type = 0; + /* + * Disabling all counters initially, they will be enabled + * either manually by us or by kernel via enable_on_exec + * set later. + */ + if (perf_evsel__is_group_leader(evsel)) + attr->disabled = 1; + if (target__has_cpu(&target)) return perf_evsel__open_per_cpu(evsel, perf_evsel__cpus(evsel)); if (!target__has_task(&target) && perf_evsel__is_group_leader(evsel)) { - attr->disabled = 1; if (!initial_delay) attr->enable_on_exec = 1; } @@ -251,12 +258,18 @@ static void process_interval(void) print_counters(&rs, 0, NULL); } -static void handle_initial_delay(void) +static void enable_counters(void) { - if (initial_delay) { + if (initial_delay) usleep(initial_delay * 1000); + + /* + * We need to enable counters only if: + * - we don't have tracee (attaching to task or cpu) + * - we have initial delay configured + */ + if (!target__none(&target) || initial_delay) perf_evlist__enable(evsel_list); - } } static volatile int workload_exec_errno; @@ -353,7 +366,7 @@ static int __run_perf_stat(int argc, const char **argv) if (forks) { perf_evlist__start_workload(evsel_list); - handle_initial_delay(); + enable_counters(); if (interval) { while (!waitpid(child_pid, &status, WNOHANG)) { @@ -372,7 +385,7 @@ static int __run_perf_stat(int argc, const char **argv) if (WIFSIGNALED(status)) psignal(WTERMSIG(status), argv[0]); } else { - handle_initial_delay(); + enable_counters(); while (!done) { nanosleep(&ts, NULL); if (interval) -- 2.30.2