From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-yh0-f42.google.com (mail-yh0-f42.google.com [209.85.213.42]) by kanga.kvack.org (Postfix) with ESMTP id 727716B006E for ; Tue, 9 Jun 2015 16:02:53 -0400 (EDT) Received: by yhak3 with SMTP id k3so11641383yha.2 for ; Tue, 09 Jun 2015 13:02:53 -0700 (PDT) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id y28si3110952yhy.53.2015.06.09.13.02.52 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 09 Jun 2015 13:02:52 -0700 (PDT) Message-ID: <55774664.6060402@redhat.com> Date: Tue, 09 Jun 2015 16:02:44 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH 3/4] mm: Defer flush of writable TLB entries References: <1433871118-15207-1-git-send-email-mgorman@suse.de> <1433871118-15207-4-git-send-email-mgorman@suse.de> In-Reply-To: <1433871118-15207-4-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman , Andrew Morton Cc: Hugh Dickins , Minchan Kim , Dave Hansen , Andi Kleen , H Peter Anvin , Ingo Molnar , Linus Torvalds , Thomas Gleixner , Peter Zijlstra , Linux-MM , LKML On 06/09/2015 01:31 PM, Mel Gorman wrote: > If a PTE is unmapped and it's dirty then it was writable recently. Due > to deferred TLB flushing, it's best to assume a writable TLB cache entry > exists. With that assumption, the TLB must be flushed before any IO can > start or the page is freed to avoid lost writes or data corruption. This > patch defers flushing of potentially writable TLBs as long as possible. > > Signed-off-by: Mel Gorman Acked-by: Rik van Riel -- All rights reversed -- 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933364AbbFIUC5 (ORCPT ); Tue, 9 Jun 2015 16:02:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57966 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753616AbbFIUCu (ORCPT ); Tue, 9 Jun 2015 16:02:50 -0400 Message-ID: <55774664.6060402@redhat.com> Date: Tue, 09 Jun 2015 16:02:44 -0400 From: Rik van Riel User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.4.0 MIME-Version: 1.0 To: Mel Gorman , Andrew Morton CC: Hugh Dickins , Minchan Kim , Dave Hansen , Andi Kleen , H Peter Anvin , Ingo Molnar , Linus Torvalds , Thomas Gleixner , Peter Zijlstra , Linux-MM , LKML Subject: Re: [PATCH 3/4] mm: Defer flush of writable TLB entries References: <1433871118-15207-1-git-send-email-mgorman@suse.de> <1433871118-15207-4-git-send-email-mgorman@suse.de> In-Reply-To: <1433871118-15207-4-git-send-email-mgorman@suse.de> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/09/2015 01:31 PM, Mel Gorman wrote: > If a PTE is unmapped and it's dirty then it was writable recently. Due > to deferred TLB flushing, it's best to assume a writable TLB cache entry > exists. With that assumption, the TLB must be flushed before any IO can > start or the page is freed to avoid lost writes or data corruption. This > patch defers flushing of potentially writable TLBs as long as possible. > > Signed-off-by: Mel Gorman Acked-by: Rik van Riel -- All rights reversed