From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753756AbcDNMAH (ORCPT ); Thu, 14 Apr 2016 08:00:07 -0400 Received: from mga01.intel.com ([192.55.52.88]:30310 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753003AbcDNMAF (ORCPT ); Thu, 14 Apr 2016 08:00:05 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,484,1455004800"; d="scan'208";a="958568534" From: Alexander Shishkin To: Peter Zijlstra Cc: Ingo Molnar , linux-kernel@vger.kernel.org, vince@deater.net, eranian@google.com, Arnaldo Carvalho de Melo , Borislav Petkov , Alexander Shishkin , Daniel Lezcano Subject: [PATCH] perf, x86: Don't use clock function pointer to determine clock Date: Thu, 14 Apr 2016 14:59:49 +0300 Message-Id: <1460635189-2320-1-git-send-email-alexander.shishkin@linux.intel.com> X-Mailer: git-send-email 2.8.0.rc3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Now that local_clock() is explicitly inlined in sched.h, taking its pointer would uninline it in the compilation unit where it's done, making (among other things) comparing pointers to this function produce different results in different compilation units. Case in point, x86 perf core's user page updating function compares event's clock against &local_clock to see if it needs to set zero time offset related bits in the page. This patch fixes the latter by looking at the "use_clockid" event attribute instead, to determine whether local clock is used. Fixing the uninlined local_clock() in perf core is left as an exercise for the author of the prior work. Cc: Daniel Lezcano Fixes: http://lkml.kernel.org/r/1459541050-13654-1-git-send-email-daniel.lezcano@linaro.org Signed-off-by: Alexander Shishkin --- arch/x86/events/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 002b2eadd6..945ce189f5 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2177,7 +2177,7 @@ void arch_perf_update_userpage(struct perf_event *event, * cap_user_time_zero doesn't make sense when we're using a different * time base for the records. */ - if (event->clock == &local_clock) { + if (!event->attr.use_clockid) { userpg->cap_user_time_zero = 1; userpg->time_zero = data->cyc2ns_offset; } -- 2.8.0.rc3