From 96039c7c52e03b7d6dd773664e74b79e3ae9856a Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Thu, 8 Dec 2016 23:47:50 +0900 Subject: perf sched timehist: Split is_idle_sample() The is_idle_sample() function actually does more than determining whether sample come from idle task. Split the callchain part into save_task_callchain() to make it clearer. Also checking prev_pid from trace data looks preferred than just checking sample->pid since it's possible, although rare, to have invalid 0 pid/tid on scheduling an exiting task. Signed-off-by: Namhyung Kim Acked-by: David Ahern Cc: Andi Kleen Cc: Jiri Olsa Cc: Minchan Kim Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/20161208144755.16673-2-namhyung@kernel.org [ Remove some needless () in some return statements ] Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-sched.c | 39 ++++++++++++++++++++------------------- 1 file changed, 20 insertions(+), 19 deletions(-) diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index 1a3f1be93372..966eddce1609 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -1939,39 +1939,40 @@ static void timehist_update_runtime_stats(struct thread_runtime *r, r->total_run_time += r->dt_run; } -static bool is_idle_sample(struct perf_sched *sched, - struct perf_sample *sample, - struct perf_evsel *evsel, - struct machine *machine) +static bool is_idle_sample(struct perf_sample *sample, + struct perf_evsel *evsel) { - struct thread *thread; - struct callchain_cursor *cursor = &callchain_cursor; - /* pid 0 == swapper == idle task */ - if (sample->pid == 0) - return true; + if (strcmp(perf_evsel__name(evsel), "sched:sched_switch") == 0) + return perf_evsel__intval(evsel, sample, "prev_pid") == 0; - if (strcmp(perf_evsel__name(evsel), "sched:sched_switch") == 0) { - if (perf_evsel__intval(evsel, sample, "prev_pid") == 0) - return true; - } + return sample->pid == 0; +} + +static void save_task_callchain(struct perf_sched *sched, + struct perf_sample *sample, + struct perf_evsel *evsel, + struct machine *machine) +{ + struct callchain_cursor *cursor = &callchain_cursor; + struct thread *thread; /* want main thread for process - has maps */ thread = machine__findnew_thread(machine, sample->pid, sample->pid); if (thread == NULL) { pr_debug("Failed to get thread for pid %d.\n", sample->pid); - return false; + return; } if (!symbol_conf.use_callchain || sample->callchain == NULL) - return false; + return; if (thread__resolve_callchain(thread, cursor, evsel, sample, NULL, NULL, sched->max_stack + 2) != 0) { if (verbose) error("Failed to resolve callchain. Skipping\n"); - return false; + return; } callchain_cursor_commit(cursor); @@ -1994,8 +1995,6 @@ static bool is_idle_sample(struct perf_sched *sched, callchain_cursor_advance(cursor); } - - return false; } /* @@ -2111,7 +2110,7 @@ static struct thread *timehist_get_thread(struct perf_sched *sched, { struct thread *thread; - if (is_idle_sample(sched, sample, evsel, machine)) { + if (is_idle_sample(sample, evsel)) { thread = get_idle_thread(sample->cpu); if (thread == NULL) pr_err("Failed to get idle thread for cpu %d.\n", sample->cpu); @@ -2124,6 +2123,8 @@ static struct thread *timehist_get_thread(struct perf_sched *sched, pr_debug("Failed to get thread for tid %d. skipping sample.\n", sample->tid); } + + save_task_callchain(sched, sample, evsel, machine); } return thread; -- cgit v1.2.3