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 <fweisbec@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <4bea9d2f.d60ce30a.0b5b.08e1@mx.google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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 @@
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 @@
hexadecimal event descriptor.
-i::
---inherit::
- child tasks inherit counters
+--no-inherit::
+ child tasks do not inherit counters
-p::
--pid=<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 *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 @@
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 @@
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 @@
"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 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 @@
++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 @@
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,