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 563FDC4338F for ; Tue, 10 Aug 2021 02:47:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31A5B60F25 for ; Tue, 10 Aug 2021 02:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233555AbhHJCsK (ORCPT ); Mon, 9 Aug 2021 22:48:10 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:38646 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232968AbhHJCsJ (ORCPT ); Mon, 9 Aug 2021 22:48:09 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628563667; 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=UaCBCwtuyOPqEJj0WTFZHGBTav9viELzb4W8hqTN36E=; b=Ckg6mlERWGQgnrvJ5twju1YVYIG5fucjnjgQCQG0czLmk+CVIItV/ux+mNUB4+7TDLe7fI 7+tugesVg3/4o2fBLJDY7CIM1ZPo/ELO4XhkkMdJugEmH0mc7odAQ4XE8ktlATC4owCsf7 ov44UuKQcDB9uLX++xDLlrK6Uer0kD8= 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-54-kakqJMgSPKy5OwCCsylqhQ-1; Mon, 09 Aug 2021 22:47:44 -0400 X-MC-Unique: kakqJMgSPKy5OwCCsylqhQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 25FE7875047; Tue, 10 Aug 2021 02:47:43 +0000 (UTC) Received: from T590 (ovpn-13-190.pek2.redhat.com [10.72.13.190]) by smtp.corp.redhat.com (Postfix) with ESMTPS id D81CF5D9DC; Tue, 10 Aug 2021 02:47:36 +0000 (UTC) Date: Tue, 10 Aug 2021 10:47:32 +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 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org 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. -- Ming