Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751904AbaGGG3G (ORCPT ); Mon, 7 Jul 2014 02:29:06 -0400 Received: from mga09.intel.com ([134.134.136.24]:36667 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751717AbaGGG3D (ORCPT ); Mon, 7 Jul 2014 02:29:03 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.01,616,1400050800"; d="scan'208";a="539565520" From: "Yan, Zheng" To: linux-kernel@vger.kernel.org Cc: a.p.zijlstra@chello.nl, mingo@kernel.org, acme@infradead.org, eranian@google.com, andi@firstfloor.org, "Yan, Zheng" Subject: [PATCH v5 06/16] perf, core: always switch pmu specific data during context switch Date: Mon, 7 Jul 2014 14:28:35 +0800 Message-Id: <1404714527-18603-7-git-send-email-zheng.z.yan@intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: <1404714527-18603-1-git-send-email-zheng.z.yan@intel.com> References: <1404714527-18603-1-git-send-email-zheng.z.yan@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- kernel/events/core.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 51e221e..df14a4e 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -2347,6 +2347,9 @@ 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); -- 1.9.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/