From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753789AbbIMP1S (ORCPT ); Sun, 13 Sep 2015 11:27:18 -0400 Received: from casper.infradead.org ([85.118.1.10]:59745 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752992AbbIMP1R (ORCPT ); Sun, 13 Sep 2015 11:27:17 -0400 From: Arnaldo Carvalho de Melo To: Ingo Molnar Cc: linux-kernel@vger.kernel.org, Arnaldo Carvalho de Melo , Adrian Hunter , Borislav Petkov , David Ahern , Frederic Weisbecker , Jiri Olsa , Kan Liang , Stephane Eranian , Wang Nan Subject: [PATCH 1/1] perf header: Fixup reading of HEADER_NRCPUS feature Date: Sun, 13 Sep 2015 12:27:00 -0300 Message-Id: <1442158020-20014-2-git-send-email-acme@kernel.org> X-Mailer: git-send-email 2.1.0 In-Reply-To: <1442158020-20014-1-git-send-email-acme@kernel.org> References: <1442158020-20014-1-git-send-email-acme@kernel.org> X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Arnaldo Carvalho de Melo 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 Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Kan Liang Cc: Stephane Eranian Cc: Wang Nan 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 --- 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 41814547da15..fce6634aebe2 100644 --- a/tools/perf/util/header.c +++ b/tools/perf/util/header.c @@ -1438,7 +1438,7 @@ 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)) @@ -1447,7 +1447,7 @@ 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; } -- 2.1.0