diff options
| author | Kan Liang <kan.liang@linux.intel.com> | 2018-07-09 07:15:22 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-19 22:41:28 +0200 |
| commit | d8551bc50c57d914511f75cca73fd0676dd11f8f (patch) | |
| tree | 460064e67a2e2eb671c6b37d9fd7f834162be0c6 /tools | |
| parent | 96e8b14b1f42b6530154646588827d9db4e60786 (diff) | |
perf evlist: Fix error out while applying initial delay and LBR
[ Upstream commit 95035c5e167ae6e740b1ddd30210ae0eaf39a5db ]
'perf record' will error out if both --delay and LBR are applied.
For example:
# perf record -D 1000 -a -e cycles -j any -- sleep 2
Error:
dummy:HG: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
#
A dummy event is added implicitly for initial delay, which has the same
configurations as real sampling events. The dummy event is a software
event. If LBR is configured, perf must error out.
The dummy event will only be used to track PERF_RECORD_MMAP while perf
waits for the initial delay to enable the real events. The BRANCH_STACK
bit can be safely cleared for the dummy event.
After applying the patch:
# perf record -D 1000 -a -e cycles -j any -- sleep 2
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 1.054 MB perf.data (828 samples) ]
#
Reported-by: Sunil K Pandey <sunil.k.pandey@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1531145722-16404-1-git-send-email-kan.liang@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/evsel.c | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 94fce4f537e9..0d5504751cc5 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -848,6 +848,12 @@ static void apply_config_terms(struct perf_evsel *evsel, } } +static bool is_dummy_event(struct perf_evsel *evsel) +{ + return (evsel->attr.type == PERF_TYPE_SOFTWARE) && + (evsel->attr.config == PERF_COUNT_SW_DUMMY); +} + /* * The enable_on_exec/disabled value strategy: * @@ -1086,6 +1092,14 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts, else perf_evsel__reset_sample_bit(evsel, PERIOD); } + + /* + * For initial_delay, a dummy event is added implicitly. + * The software event will trigger -EOPNOTSUPP error out, + * if BRANCH_STACK bit is set. + */ + if (opts->initial_delay && is_dummy_event(evsel)) + perf_evsel__reset_sample_bit(evsel, BRANCH_STACK); } static int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads) |