[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <bb37a2ec9ac66f7dbf181a59abc495f47dc2c5b9.1446021555.git.jslaby@suse.cz>
Date: Wed, 28 Oct 2015 14:50:39 +0100
From: Jiri Slaby <jslaby@...e.cz>
To: stable@...r.kernel.org
Cc: linux-kernel@...r.kernel.org,
Arnaldo Carvalho de Melo <acme@...hat.com>,
Adrian Hunter <adrian.hunter@...el.com>,
Borislav Petkov <bp@...e.de>, David Ahern <dsahern@...il.com>,
Frederic Weisbecker <fweisbec@...il.com>,
Jiri Olsa <jolsa@...nel.org>, Kan Liang <kan.liang@...el.com>,
Stephane Eranian <eranian@...gle.com>,
Wang Nan <wangnan0@...wei.com>, Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 3.12 022/123] perf header: Fixup reading of HEADER_NRCPUS feature
From: Arnaldo Carvalho de Melo <acme@...hat.com>
3.12-stable review patch. If anyone has any objections, please let me know.
===============
commit caa470475d9b59eeff093ae650800d34612c4379 upstream.
The original patch introducing this header wrote the number of CPUs available
and online in one order and then swapped those values when reading, fix it.
Before:
# perf record usleep 1
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 4
# nrcpus avail : 4
# echo 0 > /sys/devices/system/cpu/cpu2/online
# perf record usleep 1
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 4
# nrcpus avail : 3
# echo 0 > /sys/devices/system/cpu/cpu1/online
# perf record usleep 1
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 4
# nrcpus avail : 2
After the fix, bringing back the CPUs online:
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 2
# nrcpus avail : 4
# echo 1 > /sys/devices/system/cpu/cpu2/online
# perf record usleep 1
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 3
# nrcpus avail : 4
# echo 1 > /sys/devices/system/cpu/cpu1/online
# perf record usleep 1
# perf report --header-only | grep 'nrcpus \(online\|avail\)'
# nrcpus online : 4
# nrcpus avail : 4
Acked-by: Namhyung Kim <namhyung@...nel.org>
Cc: Adrian Hunter <adrian.hunter@...el.com>
Cc: Borislav Petkov <bp@...e.de>
Cc: David Ahern <dsahern@...il.com>
Cc: Frederic Weisbecker <fweisbec@...il.com>
Cc: Jiri Olsa <jolsa@...nel.org>
Cc: Kan Liang <kan.liang@...el.com>
Cc: Stephane Eranian <eranian@...gle.com>
Cc: Wang Nan <wangnan0@...wei.com>
Fixes: fbe96f29ce4b ("perf tools: Make perf.data more self-descriptive (v8)")
Link: http://lkml.kernel.org/r/20150911153323.GP23511@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@...hat.com>
Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
tools/perf/util/header.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index c3e5a3b817ab..3f82a2f65a65 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -1718,7 +1718,7 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
if (ph->needs_swap)
nr = bswap_32(nr);
- ph->env.nr_cpus_online = nr;
+ ph->env.nr_cpus_avail = nr;
ret = readn(fd, &nr, sizeof(nr));
if (ret != sizeof(nr))
@@ -1727,7 +1727,7 @@ static int process_nrcpus(struct perf_file_section *section __maybe_unused,
if (ph->needs_swap)
nr = bswap_32(nr);
- ph->env.nr_cpus_avail = nr;
+ ph->env.nr_cpus_online = nr;
return 0;
}
--
2.6.2
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists