perf evsel: Fix use of inherit

perf stat doesn't mmap and its perfectly fine for it to use task-bound
counters with inheritance.

So set the attr.inherit on the caller and leave the syscall itself to
validate it.

When the mmap fails perf_evlist__mmap will just emit a warning if this
is the failure reason.

Reported-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
Link: http://lkml.kernel.org/r/20110414170121.GC3229@ghostprotocols.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Arnaldo Carvalho de Melo
2011-04-14 11:20:14 -03:00
parent db9a9cbc81
commit 5d2cd90922
8 changed files with 42 additions and 43 deletions

View File

@ -163,6 +163,7 @@ static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
struct perf_event_attr *attr = &evsel->attr;
int track = !evsel->idx; /* only the first counter needs these */
attr->inherit = !no_inherit;
attr->read_format = PERF_FORMAT_TOTAL_TIME_ENABLED |
PERF_FORMAT_TOTAL_TIME_RUNNING |
PERF_FORMAT_ID;
@ -251,6 +252,9 @@ static void open_counters(struct perf_evlist *evlist)
{
struct perf_evsel *pos;
if (evlist->cpus->map[0] < 0)
no_inherit = true;
list_for_each_entry(pos, &evlist->entries, node) {
struct perf_event_attr *attr = &pos->attr;
/*
@ -271,8 +275,7 @@ static void open_counters(struct perf_evlist *evlist)
retry_sample_id:
attr->sample_id_all = sample_id_all_avail ? 1 : 0;
try_again:
if (perf_evsel__open(pos, evlist->cpus, evlist->threads, group,
!no_inherit) < 0) {
if (perf_evsel__open(pos, evlist->cpus, evlist->threads, group) < 0) {
int err = errno;
if (err == EPERM || err == EACCES) {