perf evsel: Override attr->sample_period for non-libpfm4 events
authorGerman Gomez <german.gomez@arm.com>
Tue, 18 Jan 2022 14:40:54 +0000 (14:40 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 27 Jan 2022 10:05:27 +0000 (11:05 +0100)
commitc2a957a6f25242ff03a5b5039e0468450aae4896
tree9cc3dbd941f28bdbc862ee7244a04565e663197d
parent95429d6b64b1f6ed5fff4b91b9f8eb5fbf337c0d
perf evsel: Override attr->sample_period for non-libpfm4 events

commit 3606c0e1a1050d397ad759a62607e419fd8b0ccb upstream.

A previous patch preventing "attr->sample_period" values from being
overridden in pfm events changed a related behaviour in arm-spe.

Before said patch:

  perf record -c 10000 -e arm_spe_0// -- sleep 1

Would yield an SPE event with period=10000. After the patch, the period
in "-c 10000" was being ignored because the arm-spe code initializes
sample_period to a non-zero value.

This patch restores the previous behaviour for non-libpfm4 events.

Fixes: ae5dcc8abe31 (“perf record: Prevent override of attr->sample_period for libpfm4 events”)
Reported-by: Chase Conklin <chase.conklin@arm.com>
Signed-off-by: German Gomez <german.gomez@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20220118144054.2541-1-german.gomez@arm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tools/perf/util/evsel.c