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/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,