From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id ECEF2600580 for ; Thu, 7 Jan 2010 14:24:57 -0500 (EST) Date: Thu, 7 Jan 2010 13:24:33 -0600 (CST) From: Christoph Lameter Subject: Re: [RFC][PATCH 6/8] mm: handle_speculative_fault() In-Reply-To: Message-ID: References: <20100104182429.833180340@chello.nl> <20100104182813.753545361@chello.nl> <20100105054536.44bf8002@infradead.org> <20100105192243.1d6b2213@infradead.org> <1262884960.4049.106.camel@laptop> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Linus Torvalds Cc: Peter Zijlstra , 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, 7 Jan 2010, Linus Torvalds wrote: > + if (brk < cur_brk) > + goto slow_case; > + if (brk == cur_brk) > + goto out; > + > + vma = ok_to_extend_brk(mm, cur_brk, brk); > + if (!vma) > + goto slow_case; > + > + spin_lock(&mm->page_table_lock); page_table_lock used to serialize multiple fast brks? CONFIG_SPLIT_PTLOCK implies that code will not use this lock in fault handling. So no serialization with faults. Also the current code assumes vm_end and so on to be stable if mmap_sem is held. F.e. find_vma() from do_fault is now running while vm_end may be changing under it. -- 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