From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752640AbdFQHnr (ORCPT ); Sat, 17 Jun 2017 03:43:47 -0400 Received: from szxga02-in.huawei.com ([45.249.212.188]:8319 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752477AbdFQHnq (ORCPT ); Sat, 17 Jun 2017 03:43:46 -0400 From: Zhou Chengming To: , CC: , , , , Subject: [PATCH] perf/core: make sure group events are for the same cpu Date: Sat, 17 Jun 2017 15:42:12 +0800 Message-ID: <1497685332-122353-1-git-send-email-zhouchengming1@huawei.com> X-Mailer: git-send-email 1.8.3.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.175.113.25] X-CFilter-Loop: Reflected X-Mirapoint-Virus-RAPID-Raw: score=unknown(0), refid=str=0001.0A0B0208.5944DD6E.0030,ss=1,re=0.000,recu=0.000,reip=0.000,cl=1,cld=1,fgs=0, ip=0.0.0.0, so=2014-11-16 11:51:01, dmn=2013-03-21 17:37:32 X-Mirapoint-Loop-Id: b9defd4c6ec8b34e104bb826a3940f92 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The else branch are broken for taskctx: two events can on the same taskctx, but on different cpu. This patch fix it, we don't need to check move_group. We first make sure we're on the same task, or both per-cpu events, and then make sure we're events for the same cpu. Signed-off-by: Zhou Chengming --- kernel/events/core.c | 31 +++++++++++-------------------- 1 file changed, 11 insertions(+), 20 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 6c4e523..59270bd 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -10010,28 +10010,19 @@ static int perf_event_set_clock(struct perf_event *event, clockid_t clk_id) goto err_context; /* - * Do not allow to attach to a group in a different - * task or CPU context: + * Make sure we're both on the same task, or both + * per-cpu events. */ - if (move_group) { - /* - * Make sure we're both on the same task, or both - * per-cpu events. - */ - if (group_leader->ctx->task != ctx->task) - goto err_context; + if (group_leader->ctx->task != ctx->task) + goto err_context; - /* - * Make sure we're both events for the same CPU; - * grouping events for different CPUs is broken; since - * you can never concurrently schedule them anyhow. - */ - if (group_leader->cpu != event->cpu) - goto err_context; - } else { - if (group_leader->ctx != ctx) - goto err_context; - } + /* + * Make sure we're both events for the same CPU; + * grouping events for different CPUs is broken; since + * you can never concurrently schedule them anyhow. + */ + if (group_leader->cpu != event->cpu) + goto err_context; /* * Only a group leader can be exclusive or pinned -- 1.8.3.1