From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751970AbbIBDBx (ORCPT ); Tue, 1 Sep 2015 23:01:53 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:41271 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751240AbbIBDBw (ORCPT ); Tue, 1 Sep 2015 23:01:52 -0400 Message-ID: <55E66690.800@huawei.com> Date: Wed, 2 Sep 2015 11:01:36 +0800 From: "Wangnan (F)" User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:31.0) Gecko/20100101 Thunderbird/31.6.0 MIME-Version: 1.0 To: CC: , Alexei Starovoitov , Jiri Olsa , Masami Hiramatsu , Namhyung Kim , Zefan Li , Subject: Re: [PATCH] perf tools: Don't set leader if parser doesn't collect an evsel References: <1440822125-52691-3-git-send-email-wangnan0@huawei.com> <1441162427-114014-1-git-send-email-wangnan0@huawei.com> In-Reply-To: <1441162427-114014-1-git-send-email-wangnan0@huawei.com> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.111.66.109] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2015/9/2 10:53, Wang Nan wrote: > Similar to patch 'perf tools: Don't set cmdline_group_boundary if no > evsel is collected', in case when parser collects no evsel (at this > point it shouldn't happen), parse_events__set_leader() is not safe. > > This patch checks list_empty becore calling __perf_evlist__set_leader() > for safty reason. > > Signed-off-by: Wang Nan > Cc: Arnaldo Carvalho de Melo > Cc: Alexei Starovoitov > Cc: Jiri Olsa > Cc: Masami Hiramatsu > Cc: Namhyung Kim > Cc: Zefan Li > Cc: pi3orama@163.com > --- > > I'd like to queue this patch into my next pull request. Since it is not > a real bug, it may be dropped. I think merging this into patch 2/31 should be better. If we decide to drop then only one patch should be considered. > --- > tools/perf/util/parse-events.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c > index f2c0317..836d226 100644 > --- a/tools/perf/util/parse-events.c > +++ b/tools/perf/util/parse-events.c > @@ -793,6 +793,9 @@ void parse_events__set_leader(char *name, struct list_head *list) > { > struct perf_evsel *leader; > > + if (list_empty(list)) > + return; > + > __perf_evlist__set_leader(list); > leader = list_entry(list->next, struct perf_evsel, node); > leader->group_name = name ? strdup(name) : NULL;