Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761626AbYC0NVu (ORCPT ); Thu, 27 Mar 2008 09:21:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759511AbYC0NV2 (ORCPT ); Thu, 27 Mar 2008 09:21:28 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:40731 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758985AbYC0NV1 (ORCPT ); Thu, 27 Mar 2008 09:21:27 -0400 Subject: Re: What if a TLB flush needed to sleep? From: Peter Zijlstra To: Christoph Lameter Cc: Thomas Gleixner , "Luck, Tony" , linux-arch@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org In-Reply-To: References: <1FE6DD409037234FAB833C420AA843ECE9DF60@orsmsx424.amr.corp.intel.com> Content-Type: text/plain Date: Thu, 27 Mar 2008 14:20:52 +0100 Message-Id: <1206624052.8514.570.camel@twins> Mime-Version: 1.0 X-Mailer: Evolution 2.21.92 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 821 Lines: 21 On Wed, 2008-03-26 at 18:19 -0700, Christoph Lameter wrote: > On Wed, 26 Mar 2008, Thomas Gleixner wrote: > > > Please use a mutex, not a semaphore. semaphores should only be used > > when you need a counting sempahore. > > Seems that mutexes are mainly useful for 2 processor systems since they > do not allow concurrent read sections. We want multiple processors able > to reclaim pages within the same vma or file concurrently. This means > processors need to be able to concurrently walk potentially long lists of > vmas. confusion between semaphores and rwsems -- 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/