Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 2 Oct 2002 12:52:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 2 Oct 2002 12:52:24 -0400 Received: from pixpat.austin.ibm.com ([192.35.232.241]:43711 "EHLO baldur.austin.ibm.com") by vger.kernel.org with ESMTP id ; Wed, 2 Oct 2002 12:52:15 -0400 Date: Wed, 02 Oct 2002 11:57:26 -0500 From: Dave McCracken To: Daniel Phillips , Linux Memory Management , Linux Kernel Subject: Re: [PATCH] Snapshot of shared page tables Message-ID: <83240000.1033577846@baldur.austin.ibm.com> In-Reply-To: References: <45850000.1033570655@baldur.austin.ibm.com> X-Mailer: Mulberry/2.2.1 (Linux/x86) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1114 Lines: 27 --On Wednesday, October 02, 2002 18:51:41 +0200 Daniel Phillips wrote: > Interesting, you substituted pte_page_lock(ptepage) for > mm->page_table_lock. Could you wax poetic about that, please? Sure. If a pte page is shared, the mm->page_table_lock is not sufficient to protect the rest of the page fault. Therefore we need a lock at the pte page level. The mm->page_table_lock is held during the page fault until we have a valid and locked pte page we're working on, then it's dropped for the rest of the fault. Feel free to poke holes in my logic, but I think it's the right locking model for shared pte pages. Dave McCracken ====================================================================== Dave McCracken IBM Linux Base Kernel Team 1-512-838-3059 dmccr@us.ibm.com T/L 678-3059 - 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/