From: Stephane Eranian Date: Wed, 12 May 2010 08:40:01 +0000 (+0200) Subject: perf tools: change event inheritance logic in stat and record X-Git-Tag: v2.6.35-rc1~3^2~68 X-Git-Url: http://ftp.safe.ca/?p=safe%2Fjmp%2Flinux-2.6;a=commitdiff_plain;h=2e6cdf996ba43ce0b090ffbf754f83e17362cd69 perf tools: change event inheritance logic in stat and record By default, event inheritance across fork and pthread_create was on but the -i option of stat and record, which enabled inheritance, led to believe it was off by default. This patch fixes this logic by inverting the meaning of the -i option. By default inheritance is on whether you attach to a process (-p), a thread (-t) or start a process. If you pass -i, then you turn off inheritance. Turning off inheritance if you don't need it, helps limit perf resource usage as well. The patch also fixes perf stat -t xxxx and perf record -t xxxx which did not start the counters. Acked-by: Frederic Weisbecker Cc: David S. Miller Cc: Frédéric Weisbecker Cc: Ingo Molnar Cc: Paul Mackerras Cc: Peter Zijlstra LKML-Reference: <4bea9d2f.d60ce30a.0b5b.08e1@mx.google.com> Signed-off-by: Stephane Eranian Signed-off-by: Arnaldo Carvalho de Melo --- diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt index 020d871..34e255f 100644 --- a/tools/perf/Documentation/perf-record.txt +++ b/tools/perf/Documentation/perf-record.txt @@ -69,8 +69,8 @@ OPTIONS Output file name. -i:: ---inherit:: - Child tasks inherit counters. +--no-inherit:: + Child tasks do not inherit counters. -F:: --freq=:: Profile at this frequency. diff --git a/tools/perf/Documentation/perf-stat.txt b/tools/perf/Documentation/perf-stat.txt index 484080d..2cab8e8 100644 --- a/tools/perf/Documentation/perf-stat.txt +++ b/tools/perf/Documentation/perf-stat.txt @@ -31,8 +31,8 @@ OPTIONS hexadecimal event descriptor. -i:: ---inherit:: - child tasks inherit counters +--no-inherit:: + child tasks do not inherit counters -p:: --pid=:: stat events on existing pid diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 6b77b28..0f467cf 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -54,7 +54,7 @@ static pid_t target_tid = -1; static pid_t *all_tids = NULL; static int thread_num = 0; static pid_t child_pid = -1; -static bool inherit = true; +static bool no_inherit = false; static enum write_mode_t write_mode = WRITE_FORCE; static bool call_graph = false; static bool inherit_stat = false; @@ -298,8 +298,8 @@ static void create_counter(int counter, int cpu) attr->mmap = track; attr->comm = track; - attr->inherit = inherit; - if (target_pid == -1 && !system_wide) { + attr->inherit = !no_inherit; + if (target_pid == -1 && target_tid == -1 && !system_wide) { attr->disabled = 1; attr->enable_on_exec = 1; } @@ -641,7 +641,7 @@ static int __cmd_record(int argc, const char **argv) close(child_ready_pipe[0]); } - if ((!system_wide && !inherit) || profile_cpu != -1) { + if ((!system_wide && no_inherit) || profile_cpu != -1) { open_counters(profile_cpu); } else { nr_cpus = read_cpu_map(); @@ -821,8 +821,8 @@ static const struct option options[] = { "event period to sample"), OPT_STRING('o', "output", &output_name, "file", "output file name"), - OPT_BOOLEAN('i', "inherit", &inherit, - "child tasks inherit counters"), + OPT_BOOLEAN('i', "no-inherit", &no_inherit, + "child tasks do not inherit counters"), OPT_INTEGER('F', "freq", &user_freq, "profile at this frequency"), OPT_INTEGER('m', "mmap-pages", &mmap_pages, diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c index e619ac8..ff8c413 100644 --- a/tools/perf/builtin-stat.c +++ b/tools/perf/builtin-stat.c @@ -72,7 +72,7 @@ static unsigned int nr_cpus = 0; static int run_idx = 0; static int run_count = 1; -static bool inherit = true; +static bool no_inherit = false; static bool scale = true; static pid_t target_pid = -1; static pid_t target_tid = -1; @@ -167,8 +167,8 @@ static int create_perf_stat_counter(int counter) ++ncreated; } } else { - attr->inherit = inherit; - if (target_pid == -1) { + attr->inherit = !no_inherit; + if (target_pid == -1 && target_tid == -1) { attr->disabled = 1; attr->enable_on_exec = 1; } @@ -518,8 +518,8 @@ static const struct option options[] = { OPT_CALLBACK('e', "event", NULL, "event", "event selector. use 'perf list' to list available events", parse_events), - OPT_BOOLEAN('i', "inherit", &inherit, - "child tasks inherit counters"), + OPT_BOOLEAN('i', "no-inherit", &no_inherit, + "child tasks do not inherit counters"), OPT_INTEGER('p', "pid", &target_pid, "stat events on existing process id"), OPT_INTEGER('t', "tid", &target_tid,