From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Tue, 14 Dec 2004 12:25:11 -0800 (PST) From: Christoph Lameter Subject: Re: Anticipatory prefaulting in the page fault handler V1 In-Reply-To: <200412142124.11685.amgta@yacht.ocn.ne.jp> Message-ID: References: <200412132330.23893.amgta@yacht.ocn.ne.jp> <200412142124.11685.amgta@yacht.ocn.ne.jp> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org Return-Path: To: Akinobu Mita Cc: "Martin J. Bligh" , nickpiggin@yahoo.com.au, Jeff Garzik , torvalds@osdl.org, hugh@veritas.com, benh@kernel.crashing.org, linux-mm@kvack.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org List-ID: On Tue, 14 Dec 2004, Akinobu Mita wrote: > This is why I inserted pte_none() for each page_table in case of > read fault too. > > If read access fault occured for the address "addr". > It is completely unnecessary to check by pte_none() to the page_table > for "addr". Because page_table_lock has never been released until > do_anonymous_page returns (in case of read access fault) > > But there is not any guarantee that the page_tables for addr+PAGE_SIZE, > addr+2*PAGE_SIZE, ... have not been mapped yet. Right. Thanks for pointing that out. -- 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: aart@kvack.org