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From: Adrian Hunter <adrian.hunter@intel.com>
To: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: linux-kernel@vger.kernel.org, Jiri Olsa <jolsa@redhat.com>
Subject: [PATCH] perf tools: Fix Intel BTS/PT timestamp handling
Date: Thu, 20 Aug 2015 11:51:32 +0300	[thread overview]
Message-ID: <1440060692-5585-1-git-send-email-adrian.hunter@intel.com> (raw)

Events that don't sample the timestamp have a timestamp
value of -1.  Intel BTS and Intel PT processing wasn't
taking that into account.  This is particularly noticeable
with Intel BTS because timestamps are not requested by
default.  Then, if the conversion of -1 to TSC results
in a small number, the processing is unaffected.
However if the conversion results in a big number, then
the data is processed prematurely before relevant sideband
data like mmap events, which in turn results in samples
with unknown dsos.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
---
 tools/perf/util/intel-bts.c | 2 +-
 tools/perf/util/intel-pt.c  | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/util/intel-bts.c b/tools/perf/util/intel-bts.c
index dce99cfb1309..ea768625ab5b 100644
--- a/tools/perf/util/intel-bts.c
+++ b/tools/perf/util/intel-bts.c
@@ -610,7 +610,7 @@ static int intel_bts_process_event(struct perf_session *session,
 		return -EINVAL;
 	}
 
-	if (sample->time)
+	if (sample->time && sample->time != (u64)-1)
 		timestamp = perf_time_to_tsc(sample->time, &bts->tc);
 	else
 		timestamp = 0;
diff --git a/tools/perf/util/intel-pt.c b/tools/perf/util/intel-pt.c
index 2a4a4120473b..a5acd2fe2447 100644
--- a/tools/perf/util/intel-pt.c
+++ b/tools/perf/util/intel-pt.c
@@ -1450,7 +1450,7 @@ static int intel_pt_process_event(struct perf_session *session,
 		return -EINVAL;
 	}
 
-	if (sample->time)
+	if (sample->time && sample->time != (u64)-1)
 		timestamp = perf_time_to_tsc(sample->time, &pt->tc);
 	else
 		timestamp = 0;
-- 
1.9.1


             reply	other threads:[~2015-08-20  8:54 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-08-20  8:51 Adrian Hunter [this message]
2015-08-20 19:28 ` [PATCH] perf tools: Fix Intel BTS/PT timestamp handling Arnaldo Carvalho de Melo
2015-08-22  6:52 ` [tip:perf/core] perf tools: Fix Intel PT " tip-bot for Adrian Hunter

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