From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752279AbaKFPPq (ORCPT ); Thu, 6 Nov 2014 10:15:46 -0500 Received: from mga11.intel.com ([192.55.52.93]:37539 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751545AbaKFPJn (ORCPT ); Thu, 6 Nov 2014 10:09:43 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.07,326,1413270000"; d="scan'208";a="627701864" From: Kan Liang To: a.p.zijlstra@chello.nl, eranian@google.com Cc: linux-kernel@vger.kernel.org, mingo@redhat.com, paulus@samba.org, acme@kernel.org, jolsa@redhat.com, ak@linux.intel.com, Kan Liang Subject: [PATCH V8 06/14] perf, core: always switch pmu specific data during context switch Date: Thu, 6 Nov 2014 09:54:23 -0500 Message-Id: <1415285671-16894-7-git-send-email-kan.liang@intel.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1415285671-16894-1-git-send-email-kan.liang@intel.com> References: <1415285671-16894-1-git-send-email-kan.liang@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Yan, Zheng If two tasks were both forked from the same parent task, Events in their perf task contexts can be the same. Perf core may leave out switching the perf event contexts. Previous patch inroduces pmu specific data. The data is for saving the LBR stack, it is task specific. So we need to switch the data even when context switch is optimized out. Signed-off-by: Yan, Zheng Signed-off-by: Kan Liang --- kernel/events/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 08d6671..4360c95 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -2420,6 +2420,9 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn, next->perf_event_ctxp[ctxn] = ctx; ctx->task = next; next_ctx->task = task; + + swap(ctx->task_ctx_data, next_ctx->task_ctx_data); + do_switch = 0; perf_event_sync_stat(ctx, next_ctx); -- 1.8.3.2