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From: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
To: peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
	mark.rutland@arm.com, alexander.shishkin@linux.intel.com,
	jolsa@redhat.com, namhyung@kernel.org
Cc: linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org
Subject: [PATCH 1/3] libperf: Add processing to scale the counters obtained during the read() system call when multiplexing
Date: Fri, 20 Aug 2021 18:39:06 +0900	[thread overview]
Message-ID: <20210820093908.734503-2-nakamura.shun@fujitsu.com> (raw)
In-Reply-To: <20210820093908.734503-1-nakamura.shun@fujitsu.com>

perf_evsel__read() scales counters obtained by RDPMC during multiplexing, but
does not scale counters obtained by read() system call.

Add processing to perf_evsel__read() to scale the counters obtained during the
read() system call when multiplexing.

Signed-off-by: Shunsuke Nakamura <nakamura.shun@fujitsu.com>
---
 tools/lib/perf/evsel.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
index d8886720e83d..005cf64a1ad7 100644
--- a/tools/lib/perf/evsel.c
+++ b/tools/lib/perf/evsel.c
@@ -18,6 +18,7 @@
 #include <sys/ioctl.h>
 #include <sys/mman.h>
 #include <asm/bug.h>
+#include <linux/math64.h>
 
 void perf_evsel__init(struct perf_evsel *evsel, struct perf_event_attr *attr,
 		      int idx)
@@ -308,6 +309,9 @@ int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
 	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
 		return -errno;
 
+	if (count->ena != count->run)
+		count->val = mul_u64_u64_div64(count->val, count->ena, count->run);
+
 	return 0;
 }
 
-- 
2.25.1


  reply	other threads:[~2021-08-20  9:46 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-20  9:39 [PATCH 0/3] libperf: Add support for scaling counters obtained from the read() system call during multiplexing Shunsuke Nakamura
2021-08-20  9:39 ` Shunsuke Nakamura [this message]
2021-08-23 20:12   ` [PATCH 1/3] libperf: Add processing to scale the counters obtained during the read() system call when multiplexing Rob Herring
2021-08-24 10:11     ` nakamura.shun
2021-08-31  8:58       ` nakamura.shun
2021-08-31 12:26       ` Rob Herring
2021-09-07 23:59         ` Ian Rogers
2021-09-17  8:04           ` nakamura.shun
2021-08-20  9:39 ` [PATCH 2/3] libperf tests: Fix verbose printing Shunsuke Nakamura
2021-08-23 20:26   ` Rob Herring
2021-08-24 18:06     ` Arnaldo Carvalho de Melo
2021-08-20  9:39 ` [PATCH 3/3] libperf tests: Add test_stat_multiplexing test Shunsuke Nakamura

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