Re: [PATCH v2 1/5] perf record: Set PERF_RECORD_PERIOD if attr->freq is set.
From: Arnaldo Carvalho de Melo <acme@kernel.org>
Date: 2020-07-29 18:52:17
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Em Tue, Jul 28, 2020 at 01:57:30AM -0700, Ian Rogers escreveu:
From: David Sharp <redacted> evsel__config() would only set PERF_RECORD_PERIOD if it set attr->freq
There is no such thing as 'PERF_RECORD_PERIOD', its PERF_SAMPLE_PERIOD, also...
quoted hunk ↗ jump to hunk
from perf record options. When it is set by libpfm events, it would not get set. This changes evsel__config to see if attr->freq is set outside of whether or not it changes attr->freq itself. Signed-off-by: David Sharp <redacted> Signed-off-by: Ian Rogers <irogers@google.com> --- tools/perf/util/evsel.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index ef802f6d40c1..811f538f7d77 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c@@ -979,13 +979,18 @@ void evsel__config(struct evsel *evsel, struct record_opts *opts, if (!attr->sample_period || (opts->user_freq != UINT_MAX || opts->user_interval != ULLONG_MAX)) { if (opts->freq) { - evsel__set_sample_bit(evsel, PERIOD); attr->freq = 1; attr->sample_freq = opts->freq; } else { attr->sample_period = opts->default_interval; } } + /* + * If attr->freq was set (here or earlier), ask for period + * to be sampled. + */ + if (attr->freq) + evsel__set_sample_bit(evsel, PERIOD);
Why can't the libpfm code set opts? With this patch we will end up calling evsel__set_sample_bit(evsel, PERIOD) twice, which isn't a problem but looks strange. - Arnaldo
if (opts->no_samples) attr->sample_freq = 0; -- 2.28.0.163.g6104cc2f0b6-goog
-- - Arnaldo