Commit-ID: 35c1980eb3d1acb3cac11c38252339399dca77e3
Gitweb: http://git.kernel.org/tip/35c1980eb3d1acb3cac11c38252339399dca77e3
Author: Andi Kleen <[email protected]>
AuthorDate: Tue, 5 Sep 2017 14:13:24 -0700
Committer: Arnaldo Carvalho de Melo <[email protected]>
CommitDate: Wed, 13 Sep 2017 09:49:16 -0300
perf stat: Fall weak group back even for EBADF
It's not possible to run a package event and a per cpu event in the same
group. This is used by some of the power metrics. They work correctly
when not using a group.
Normally weak groups should handle that, but in this case EBADF is
returned instead of the normal EINVAL.
$ strace -e perf_event_open ./perf stat -v -e
'{cstate_pkg/c2-residency/,msr/tsc/}:W' -a sleep 1
Using CPUID GenuineIntel-6-3E
perf_event_open({type=0x17 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, -1, PERF_FLAG_FD_CLOEXEC) = -1 EINVAL (Invalid argument)
perf_event_open({type=0x17 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, -1, 0) = -1 EINVAL (Invalid argument)
perf_event_open({type=0x17 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, -1, 0) = -1 EINVAL (Invalid argument)
perf_event_open({type=0x17 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, -1, 0) = -1 EINVAL (Invalid argument)
perf_event_open({type=0x17 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, -1, 0) = 3
perf_event_open({type=0x7 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 0, 3, 0) = 4
perf_event_open({type=0x7 /* PERF_TYPE_??? */, size=PERF_ATTR_SIZE_VER5,
config=0, ...}, -1, 1, 0, 0) = -1 EBADF (Bad file descriptor)
and perf errors out.
Make weak groups trigger a fall back for EBADF too. Then this case works
correctly:
$ perf stat -v -e '{cstate_pkg/c2-residency/,msr/tsc/}:W' -a sleep 1
Using CPUID GenuineIntel-6-3E
Weak group for cstate_pkg/c2-residency//2 failed
cstate_pkg/c2-residency/: 476709882 1000598460 1000598460
msr/tsc/: 39625837911 12007369110 12007369110
Performance counter stats for 'system wide':
476,709,882 cstate_pkg/c2-residency/
39,625,837,911 msr/tsc/
1.000697588 seconds time elapsed
This fixes perf stat -M Power ...
$ perf stat -M Power --metric-only -a sleep 1
Performance counter stats for 'system wide':
Turbo_Utilization C3_Core_Residency C6_Core_Residency C7_Core_Residency
C2_Pkg_Residency C3_Pkg_Residency C6_Pkg_Residency C7_Pkg_Residency
1.0 0.7 30.0 0.0
0.9 0.1 0.4 0.0
1.001240740 seconds time elapsed
Signed-off-by: Andi Kleen <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/perf/builtin-stat.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/tools/perf/builtin-stat.c b/tools/perf/builtin-stat.c
index 88f1d5f..dd52541 100644
--- a/tools/perf/builtin-stat.c
+++ b/tools/perf/builtin-stat.c
@@ -656,7 +656,7 @@ try_again:
if (create_perf_stat_counter(counter) < 0) {
/* Weak group failed. Reset the group. */
- if (errno == EINVAL &&
+ if ((errno == EINVAL || errno == EBADF) &&
counter->leader != counter &&
counter->weak_group) {
counter = perf_evsel__reset_weak_group(counter);
