perf: record TRACE_INFO only if using tracepoints and SAMPLE_RAW
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From: Arnaldo Carvalho de Melo on 4 May 2010 17:20 Em Tue, May 04, 2010 at 07:06:45PM +0200, Frederic Weisbecker escreveu: > On Tue, May 04, 2010 at 11:00:05AM -0300, Arnaldo Carvalho de Melo wrote: > > From: Tom Zanussi <tzanussi(a)gmail.com> > > > > The current perf code implicitly assumes SAMPLE_RAW means tracepoints > > are being used, but doesn't check for that. It happily records the > > TRACE_INFO even if SAMPLE_RAW is used without tracepoints, but when the > > perf data is read it won't go any further when it finds TRACE_INFO but > > no tracepoints, and displays misleading errors. > > > > This adds a check for both in perf-record, and won't record TRACE_INFO > > unless both are true. This at least allows perf report -D to dump raw > > events, and avoids triggering a misleading error condition in perf > > trace. It doesn't actually enable the non-tracepoint raw events to be > > displayed in perf trace, since perf trace currently only deals with > > tracepoint events. > > > > Cc: Fr�d�ric Weisbecker <fweisbec(a)gmail.com> > > Cc: Mike Galbraith <efault(a)gmx.de> > > Cc: Paul Mackerras <paulus(a)samba.org> > > Cc: Peter Zijlstra <a.p.zijlstra(a)chello.nl> > > LKML-Reference: <1272865861.7932.16.camel(a)tropicana> > > Signed-off-by: Tom Zanussi <tzanussi(a)gmail.com> > > Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com> > > --- > > tools/perf/builtin-record.c | 35 +++++++++++++++++++++-------------- > > tools/perf/util/header.c | 1 - > > tools/perf/util/parse-events.h | 1 + > > tools/perf/util/trace-event-info.c | 5 +++++ > > 4 files changed, 27 insertions(+), 15 deletions(-) > > > > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > > index ac989e9..0ff67d1 100644 > > --- a/tools/perf/builtin-record.c > > +++ b/tools/perf/builtin-record.c > > @@ -560,11 +560,12 @@ static int __cmd_record(int argc, const char **argv) > > return err; > > } > > > > - if (raw_samples) { > > + if (raw_samples && have_tracepoints(attrs, nr_counters)) { > > perf_header__set_feat(&session->header, HEADER_TRACE_INFO); > > } else { > > > > Using get_tracepoints_path() is a bit costly just to check if we use > tracepoints as it allocates and fill the paths. Can you please send a fix? - Arnaldo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
From: Tom Zanussi on 4 May 2010 23:40
On Tue, 2010-05-04 at 18:18 -0300, Arnaldo Carvalho de Melo wrote: > Em Tue, May 04, 2010 at 07:06:45PM +0200, Frederic Weisbecker escreveu: > > On Tue, May 04, 2010 at 11:00:05AM -0300, Arnaldo Carvalho de Melo wrote: > > > From: Tom Zanussi <tzanussi(a)gmail.com> > > > > > > The current perf code implicitly assumes SAMPLE_RAW means tracepoints > > > are being used, but doesn't check for that. It happily records the > > > TRACE_INFO even if SAMPLE_RAW is used without tracepoints, but when the > > > perf data is read it won't go any further when it finds TRACE_INFO but > > > no tracepoints, and displays misleading errors. > > > > > > This adds a check for both in perf-record, and won't record TRACE_INFO > > > unless both are true. This at least allows perf report -D to dump raw > > > events, and avoids triggering a misleading error condition in perf > > > trace. It doesn't actually enable the non-tracepoint raw events to be > > > displayed in perf trace, since perf trace currently only deals with > > > tracepoint events. > > > > > > Cc: Frédéric Weisbecker <fweisbec(a)gmail.com> > > > Cc: Mike Galbraith <efault(a)gmx.de> > > > Cc: Paul Mackerras <paulus(a)samba.org> > > > Cc: Peter Zijlstra <a.p.zijlstra(a)chello.nl> > > > LKML-Reference: <1272865861.7932.16.camel(a)tropicana> > > > Signed-off-by: Tom Zanussi <tzanussi(a)gmail.com> > > > Signed-off-by: Arnaldo Carvalho de Melo <acme(a)redhat.com> > > > --- > > > tools/perf/builtin-record.c | 35 +++++++++++++++++++++-------------- > > > tools/perf/util/header.c | 1 - > > > tools/perf/util/parse-events.h | 1 + > > > tools/perf/util/trace-event-info.c | 5 +++++ > > > 4 files changed, 27 insertions(+), 15 deletions(-) > > > > > > diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c > > > index ac989e9..0ff67d1 100644 > > > --- a/tools/perf/builtin-record.c > > > +++ b/tools/perf/builtin-record.c > > > @@ -560,11 +560,12 @@ static int __cmd_record(int argc, const char **argv) > > > return err; > > > } > > > > > > - if (raw_samples) { > > > + if (raw_samples && have_tracepoints(attrs, nr_counters)) { > > > perf_header__set_feat(&session->header, HEADER_TRACE_INFO); > > > } else { > > > > > > > > Using get_tracepoints_path() is a bit costly just to check if we use > > tracepoints as it allocates and fill the paths. > > Can you please send a fix? > Yeah, there's a lot of room for improvement here - thanks for pointing it out, Frederic. The patch below should make it better... Tom From: Tom Zanussi <tzanussi(a)gmail.com> Date: Tue, 4 May 2010 22:20:16 -0500 Subject: [PATCH] perf/record: simplify TRACE_INFO tracepoint check Fix a couple of inefficiencies and redundancies related to have_tracepoints() and its use when checking whether to write TRACE_INFO. First, there's no need to use get_tracepoints_path() in have_tracepoints() - we really just want the part that checks whether any attributes correspondo to tracepoints. Second, we really don't care about raw_samples per se - tracepoints are always raw_samples. In any case, the have_tracepoints() check should be sufficient to decide whether or not to write TRACE_INFO. Signed-off-by: Tom Zanussi <tzanussi(a)gmail.com> --- tools/perf/builtin-record.c | 11 +---------- tools/perf/util/trace-event-info.c | 8 +++++++- 2 files changed, 8 insertions(+), 11 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 0ff67d1..d3981ac 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -560,17 +560,8 @@ static int __cmd_record(int argc, const char **argv) return err; } - if (raw_samples && have_tracepoints(attrs, nr_counters)) { + if (have_tracepoints(attrs, nr_counters)) perf_header__set_feat(&session->header, HEADER_TRACE_INFO); - } else { - for (i = 0; i < nr_counters; i++) { - if (attrs[i].sample_type & PERF_SAMPLE_RAW && - attrs[i].type == PERF_TYPE_TRACEPOINT) { - perf_header__set_feat(&session->header, HEADER_TRACE_INFO); - break; - } - } - } atexit(atexit_header); diff --git a/tools/perf/util/trace-event-info.c b/tools/perf/util/trace-event-info.c index 0a1fb9d..b157260 100644 --- a/tools/perf/util/trace-event-info.c +++ b/tools/perf/util/trace-event-info.c @@ -489,7 +489,13 @@ get_tracepoints_path(struct perf_event_attr *pattrs, int nb_events) bool have_tracepoints(struct perf_event_attr *pattrs, int nb_events) { - return get_tracepoints_path(pattrs, nb_events) ? true : false; + int i; + + for (i = 0; i < nb_events; i++) + if (pattrs[i].type == PERF_TYPE_TRACEPOINT) + return true; + + return false; } int read_tracing_data(int fd, struct perf_event_attr *pattrs, int nb_events) -- 1.6.4.GIT -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo(a)vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ |