From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7674C4338F for ; Tue, 10 Aug 2021 03:28:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 893BC61051 for ; Tue, 10 Aug 2021 03:28:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236572AbhHJD3R (ORCPT ); Mon, 9 Aug 2021 23:29:17 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:45470 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236799AbhHJD3N (ORCPT ); Mon, 9 Aug 2021 23:29:13 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628566131; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=zU+tbeF5cdcnLxTRgRGaA9ZLrJOz63y76gvrboLDlDI=; b=W/g15d9sXk3ZYRbvb7X4GtGrwy1+zgdyjy/XtEYwYwgj6Ix7t8FkmF0a8Lq4/6M+6MvXoK VLnEeC1XFuvkmPSzrh+y7xFmRFP7LXGDP2OsLEFlPfXKoUrnV0t1TUm+aLk/OJ41V7VrG1 aFTyPO6mbLbHx0TNyt6PX+s990/L4GE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-291-qDEt7pi5NryyMkDZYSr9og-1; Mon, 09 Aug 2021 23:28:47 -0400 X-MC-Unique: qDEt7pi5NryyMkDZYSr9og-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 52EF5801B3C; Tue, 10 Aug 2021 03:28:46 +0000 (UTC) Received: from T590 (ovpn-13-190.pek2.redhat.com [10.72.13.190]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 671A419D9B; Tue, 10 Aug 2021 03:28:39 +0000 (UTC) Date: Tue, 10 Aug 2021 11:28:34 +0800 From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, Christoph Hellwig , Oleksandr Natalenko Subject: Re: [PATCH] block: return ELEVATOR_DISCARD_MERGE if possible Message-ID: References: <20210729034226.1591070-1-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Mon, Aug 09, 2021 at 08:55:16PM -0600, Jens Axboe wrote: > On 8/9/21 8:47 PM, Ming Lei wrote: > > On Mon, Aug 09, 2021 at 02:36:25PM -0600, Jens Axboe wrote: > >> On 8/4/21 9:35 PM, Ming Lei wrote: > >>> On Thu, Jul 29, 2021 at 11:42:26AM +0800, Ming Lei wrote: > >>>> When merging one bio to request, if they are discard IO and the queue > >>>> supports multi-range discard, we need to return ELEVATOR_DISCARD_MERGE > >>>> because both block core and related drivers(nvme, virtio-blk) doesn't > >>>> handle mixed discard io merge(traditional IO merge together with > >>>> discard merge) well. > >>>> > >>>> Fix the issue by returning ELEVATOR_DISCARD_MERGE in this situation, > >>>> so both blk-mq and drivers just need to handle multi-range discard. > >>>> > >>>> Reported-by: Oleksandr Natalenko > >>>> Signed-off-by: Ming Lei > >>> > >>> Hello Jens and Guys, > >>> > >>> Ping... > >> > >> Since this isn't a new regression this release and since this kind > >> of change always makes me a bit nervous, any objections to queueing > >> it up for 5.15 with the stable/fixes tags? > > > > Fine, will post a new version with fixes tag. > > Sorry if I wasn't clear, I mean are you fine with queueing this for > 5.15? I already did add the fixes tag. Sorry for misunderstanding your point, yeah, I am fine with queuing in 5.15. Thanks, Ming