Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933064AbZJMGk7 (ORCPT ); Tue, 13 Oct 2009 02:40:59 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758968AbZJMGk7 (ORCPT ); Tue, 13 Oct 2009 02:40:59 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:52939 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756793AbZJMGk6 (ORCPT ); Tue, 13 Oct 2009 02:40:58 -0400 Date: Tue, 13 Oct 2009 08:40:06 +0200 From: Ingo Molnar To: Jason Gunthorpe Cc: Pavel Machek , Roland Dreier , Peter Zijlstra , linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, Paul Mackerras , Anton Blanchard , general@lists.openfabrics.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, Jeff Squyres Subject: Re: [ofa-general] Re: [GIT PULL] please pull ummunotify Message-ID: <20091013064006.GC9470@elte.hu> References: <1253198976.14935.27.camel@laptop> <20090929171332.GD14405@elf.ucw.cz> <20090930094456.GD24621@elte.hu> <20090930160232.GZ22310@obsidianresearch.com> <20091012181944.GF17138@elte.hu> <20091012193048.GA20313@obsidianresearch.com> <20091012202046.GA7648@elte.hu> <20091013040515.GI18578@obsidianresearch.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091013040515.GI18578@obsidianresearch.com> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 899 Lines: 21 * Jason Gunthorpe wrote: > On Mon, Oct 12, 2009 at 10:20:46PM +0200, Ingo Molnar wrote: > > It might be more acceptable because the flag-hint mechanism can at most > > cause over-flushing - while with perf events we might miss to invalidate > > a range altogether. > > Right. Overflushing is not important, but missing an event entirely is > not recoverable (at least within the current kernel APIs). So if we detect event loss in the perf event case (should not happen with sufficient buffering but it is a possibility the code should be prepared for) then we can just flush the [0,-1ULL] range, right? Ingo -- 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/