From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id 8E5A2600580 for ; Thu, 7 Jan 2010 12:23:07 -0500 (EST) Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() From: Peter Zijlstra In-Reply-To: References: <20100104182429.833180340@chello.nl> <20100104182813.753545361@chello.nl> <20100105054536.44bf8002@infradead.org> <20100105192243.1d6b2213@infradead.org> Content-Type: text/plain; charset="UTF-8" Date: Thu, 07 Jan 2010 18:22:40 +0100 Message-ID: <1262884960.4049.106.camel@laptop> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Linus Torvalds Cc: Christoph Lameter , Arjan van de Ven , "Paul E. McKenney" , KAMEZAWA Hiroyuki , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "minchan.kim@gmail.com" , "hugh.dickins" , Nick Piggin , Ingo Molnar List-ID: On Thu, 2010-01-07 at 08:19 -0800, Linus Torvalds wrote: > > So now some paths are indeed holding it for writing (or need to wait for > it to become writable). And the fairness of rwsems quite possibly then > impacts throughput a _lot_.. Right, supposing we can make this speculative fault stuff work, then we can basically reduce the mmap_sem usage in fault to: - allocating new page tables - extending the growable vmas And do everything else without holding it, including zeroing and IO. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org