This is a note to let you know that I've just added the patch titled perf evsel: Override attr->sample_period for non-libpfm4 events to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: perf-evsel-override-attr-sample_period-for-non-libpfm4-events.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 3606c0e1a1050d397ad759a62607e419fd8b0ccb Mon Sep 17 00:00:00 2001 From: German Gomez <german.gomez@xxxxxxx> Date: Tue, 18 Jan 2022 14:40:54 +0000 Subject: perf evsel: Override attr->sample_period for non-libpfm4 events MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: German Gomez <german.gomez@xxxxxxx> 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@xxxxxxx> Signed-off-by: German Gomez <german.gomez@xxxxxxx> Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx> Cc: Ian Rogers <irogers@xxxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: John Fastabend <john.fastabend@xxxxxxxxx> Cc: KP Singh <kpsingh@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Martin KaFai Lau <kafai@xxxxxx> Cc: Namhyung Kim <namhyung@xxxxxxxxxx> Cc: Song Liu <songliubraving@xxxxxx> Cc: Stephane Eranian <eranian@xxxxxxxxxx> Cc: Yonghong Song <yhs@xxxxxx> Cc: bpf@xxxxxxxxxxxxxxx Cc: netdev@xxxxxxxxxxxxxxx Link: http://lore.kernel.org/lkml/20220118144054.2541-1-german.gomez@xxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/evsel.c | 25 +++++++++++++++++-------- 1 file changed, 17 insertions(+), 8 deletions(-) --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -1014,6 +1014,17 @@ struct evsel_config_term *__evsel__get_c return found_term; } +static void evsel__set_default_freq_period(struct record_opts *opts, + struct perf_event_attr *attr) +{ + if (opts->freq) { + attr->freq = 1; + attr->sample_freq = opts->freq; + } else { + attr->sample_period = opts->default_interval; + } +} + /* * The enable_on_exec/disabled value strategy: * @@ -1080,14 +1091,12 @@ void evsel__config(struct evsel *evsel, * We default some events to have a default interval. But keep * it a weak assumption overridable by the user. */ - if (!attr->sample_period) { - if (opts->freq) { - attr->freq = 1; - attr->sample_freq = opts->freq; - } else { - attr->sample_period = opts->default_interval; - } - } + if ((evsel->is_libpfm_event && !attr->sample_period) || + (!evsel->is_libpfm_event && (!attr->sample_period || + opts->user_freq != UINT_MAX || + opts->user_interval != ULLONG_MAX))) + evsel__set_default_freq_period(opts, attr); + /* * If attr->freq was set (here or earlier), ask for period * to be sampled. Patches currently in stable-queue which might be from german.gomez@xxxxxxx are queue-5.10/perf-evsel-override-attr-sample_period-for-non-libpfm4-events.patch