From mboxrd@z Thu Jan 1 00:00:00 1970 From: Akinobu Mita Subject: Re: Anticipatory prefaulting in the page fault handler V1 Date: Tue, 14 Dec 2004 21:24:11 +0900 References: <200412132330.23893.amgta@yacht.ocn.ne.jp> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200412142124.11685.amgta@yacht.ocn.ne.jp> Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter 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 Tuesday 14 December 2004 02:10, Christoph Lameter wrote: > On Mon, 13 Dec 2004, Akinobu Mita wrote: > > 3) don't set_pte() for the entry which already have been set > > Not sure how this could have happened in the patch. 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. Anyway, I will try your V2 patch. -- 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