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=-9.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 D7183C433E2 for ; Sat, 12 Sep 2020 13:58:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6519920855 for ; Sat, 12 Sep 2020 13:58:48 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="FVGV0svF" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725854AbgILN6q (ORCPT ); Sat, 12 Sep 2020 09:58:46 -0400 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:26995 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725848AbgILN6o (ORCPT ); Sat, 12 Sep 2020 09:58:44 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1599919122; 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=sIS0z+OSHzxyt/gsTVJl97Jrp1M6RO4hEABRwxQ0KH8=; b=FVGV0svFjybEeGzLunzjnayDNkD0oze0G1oBF25EcUiojzQIWNnM+cT3BY9awBNt3fGrXt vHj0BGBTJeP2YEiIb5Pw7D6AJ1i54x8efROYqgCWKGrfhUZl35AhhYotzeNiYe4uliP4tX p5j/UTw229tZSGKVi+NEnORFC678/d0= 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-420-TEfeQITjOAWjHYtgOtea4w-1; Sat, 12 Sep 2020 09:58:38 -0400 X-MC-Unique: TEfeQITjOAWjHYtgOtea4w-1 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id EF2A58797DD; Sat, 12 Sep 2020 13:58:37 +0000 (UTC) Received: from T590 (ovpn-12-84.pek2.redhat.com [10.72.12.84]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C6CEB75129; Sat, 12 Sep 2020 13:58:26 +0000 (UTC) Date: Sat, 12 Sep 2020 21:58:22 +0800 From: Ming Lei To: Mike Snitzer Cc: Vijayendra Suman , dm-devel@redhat.com, linux-block@vger.kernel.org Subject: Re: [PATCH 2/3] block: use lcm_not_zero() when stacking chunk_sectors Message-ID: <20200912135822.GB210077@T590> References: <20200911215338.44805-1-snitzer@redhat.com> <20200911215338.44805-3-snitzer@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200911215338.44805-3-snitzer@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 Sender: linux-block-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Sep 11, 2020 at 05:53:37PM -0400, Mike Snitzer wrote: > Like 'io_opt', blk_stack_limits() should stack 'chunk_sectors' using > lcm_not_zero() rather than min_not_zero() -- otherwise the final > 'chunk_sectors' could result in sub-optimal alignment of IO to > component devices in the IO stack. > > Also, if 'chunk_sectors' isn't a multiple of 'physical_block_size' > then it is a bug in the driver and the device should be flagged as > 'misaligned'. > > Signed-off-by: Mike Snitzer > --- > block/blk-settings.c | 12 ++++++++---- > 1 file changed, 8 insertions(+), 4 deletions(-) > > diff --git a/block/blk-settings.c b/block/blk-settings.c > index 76a7e03bcd6c..b09642d5f15e 100644 > --- a/block/blk-settings.c > +++ b/block/blk-settings.c > @@ -534,6 +534,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, > > t->io_min = max(t->io_min, b->io_min); > t->io_opt = lcm_not_zero(t->io_opt, b->io_opt); > + t->chunk_sectors = lcm_not_zero(t->chunk_sectors, b->chunk_sectors); > > /* Physical block size a multiple of the logical block size? */ > if (t->physical_block_size & (t->logical_block_size - 1)) { > @@ -556,6 +557,13 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, > ret = -1; > } > > + /* chunk_sectors a multiple of the physical block size? */ > + if (t->chunk_sectors & (t->physical_block_size - 1)) { > + t->chunk_sectors = 0; > + t->misaligned = 1; > + ret = -1; > + } > + > t->raid_partial_stripes_expensive = > max(t->raid_partial_stripes_expensive, > b->raid_partial_stripes_expensive); > @@ -594,10 +602,6 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b, > t->discard_granularity; > } > > - if (b->chunk_sectors) > - t->chunk_sectors = min_not_zero(t->chunk_sectors, > - b->chunk_sectors); > - > t->zoned = max(t->zoned, b->zoned); > return ret; > } Looks fine: Reviewed-by: Ming Lei Thanks, Ming