From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754101AbbAWIo7 (ORCPT ); Fri, 23 Jan 2015 03:44:59 -0500 Received: from bombadil.infradead.org ([198.137.202.9]:33934 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753934AbbAWIo5 (ORCPT ); Fri, 23 Jan 2015 03:44:57 -0500 Date: Fri, 23 Jan 2015 09:44:51 +0100 From: Peter Zijlstra To: Shaohua Li Cc: linux-kernel@vger.kernel.org, Kernel-team@fb.com, Andy Lutomirski , Ingo Molnar Subject: Re: [RFC 2/2] perf: update userspace page info for software event Message-ID: <20150123084451.GE2896@worktop.programming.kicks-ass.net> References: <119aa7d433860f568136ab623fb4a510c28e9e6f.1421906750.git.shli@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 22, 2015 at 01:09:02PM -0800, Shaohua Li wrote: > --- > kernel/events/core.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/kernel/events/core.c b/kernel/events/core.c > index 4edde3e..4221240 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -5950,6 +5950,7 @@ static int perf_swevent_add(struct perf_event *event, int flags) > } > > hlist_add_head_rcu(&event->hlist_entry, head); > + perf_event_update_userpage(event); > > return 0; > } > @@ -6419,6 +6420,7 @@ static int cpu_clock_event_add(struct perf_event *event, int flags) > { > if (flags & PERF_EF_START) > cpu_clock_event_start(event, flags); > + perf_event_update_userpage(event); > > return 0; > } > @@ -6493,6 +6495,7 @@ static int task_clock_event_add(struct perf_event *event, int flags) > { > if (flags & PERF_EF_START) > task_clock_event_start(event, flags); > + perf_event_update_userpage(event); > > return 0; > } How about the one I sent; which adds it to {start,stop} instead of add? {start,stop} is the right place to add them, although this add might be sufficient for your use case.