From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752761Ab1KWKGP (ORCPT <rfc822;w@1wt.eu>);
	Wed, 23 Nov 2011 05:06:15 -0500
Received: from casper.infradead.org ([85.118.1.10]:49892 "EHLO
	casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1751118Ab1KWKGO convert rfc822-to-8bit (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Wed, 23 Nov 2011 05:06:14 -0500
Message-ID: <1322042767.14799.25.camel@twins>
Subject: Re: [PATCH] perf_event: fix loss of notification with multi-event
 sampling
From: Peter Zijlstra <peterz@infradead.org>
To: Stephane Eranian <eranian@google.com>
Cc: linux-kernel@vger.kernel.org, mingo@elte.hu
Date: Wed, 23 Nov 2011 11:06:07 +0100
In-Reply-To: <CABPqkBTWqPNhMBEsLmto+3=2FYjyy_b2hzq2KLbKWDFSKNktsg@mail.gmail.com>
References: <20111116145320.GA20146@quad> <1321958457.5148.17.camel@twins>
	 <CABPqkBT-ZPZC2Ku6NjyMygWUU+kMr3h9FCdKTAjvhR6ywFmNqw@mail.gmail.com>
	 <1321968559.14799.2.camel@twins>
	 <CABPqkBTWqPNhMBEsLmto+3=2FYjyy_b2hzq2KLbKWDFSKNktsg@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 8BIT
X-Mailer: Evolution 3.2.1- 
Mime-Version: 1.0
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Wed, 2011-11-23 at 10:30 +0100, Stephane Eranian wrote:
> 
> In the case of perf_event, we are not in a producer-consumer model, so
> it seems like the behavior we have now is correct. The caller of poll()
> gets stuck if the file descriptor is closed. 

But wouldn't out event->waitq still be referenced by that waiting task?
Even though we freed it in our fops->release() callback?