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=-17.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 17B1FC433DB for ; Fri, 19 Mar 2021 17:45:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C9A446197B for ; Fri, 19 Mar 2021 17:45:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229925AbhCSRoi (ORCPT ); Fri, 19 Mar 2021 13:44:38 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:42334 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230205AbhCSRod (ORCPT ); Fri, 19 Mar 2021 13:44:33 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616175873; 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=yprWRSB7vS80FLiQJh7hMRGMJTNWmDK1YYymuS08YsU=; b=cJH+0lowBQrIp9OlB6EAh1xY3zwSh9NhpEELRFbq5xRYPawodLt9a3ZrYIkLAEo7l6rcd1 xuJ08EFfiVU4YLfKzGJlYGkMuzkNe3e8UP1TbxTaTDY7zzz47ev2htHH+8E7qEkAfkMXvb zssKcujnQeC1Bg6UEBETL8xS1UW/w1I= 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-107-Z6xNQzUzO0SAJjXNwNAqiA-1; Fri, 19 Mar 2021 13:44:31 -0400 X-MC-Unique: Z6xNQzUzO0SAJjXNwNAqiA-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 D466681744F; Fri, 19 Mar 2021 17:44:29 +0000 (UTC) Received: from localhost (unknown [10.18.25.174]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 766C019C79; Fri, 19 Mar 2021 17:44:23 +0000 (UTC) Date: Fri, 19 Mar 2021 13:44:22 -0400 From: Mike Snitzer To: Ming Lei Cc: Jens Axboe , linux-block@vger.kernel.org, Christoph Hellwig , Jeffle Xu , dm-devel@redhat.com Subject: Re: [RFC PATCH V2 06/13] block: add new field into 'struct bvec_iter' Message-ID: <20210319174422.GD9938@redhat.com> References: <20210318164827.1481133-1-ming.lei@redhat.com> <20210318164827.1481133-7-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210318164827.1481133-7-ming.lei@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Mar 18 2021 at 12:48pm -0400, Ming Lei wrote: > There is a hole at the end of 'struct bvec_iter', so put a new field > here and we can save cookie returned from submit_bio() here for > supporting bio based polling. > > This way can avoid to extend bio unnecessarily. > > Signed-off-by: Ming Lei > --- > include/linux/bvec.h | 9 +++++++++ > 1 file changed, 9 insertions(+) > > diff --git a/include/linux/bvec.h b/include/linux/bvec.h > index ff832e698efb..61c0f55f7165 100644 > --- a/include/linux/bvec.h > +++ b/include/linux/bvec.h > @@ -43,6 +43,15 @@ struct bvec_iter { > > unsigned int bi_bvec_done; /* number of bytes completed in > current bvec */ > + > + /* > + * There is a hole at the end of bvec_iter, define one filed to s/filed/field/ > + * hold something which isn't relate with 'bvec_iter', so that we can s/relate/related/ or s/isn't relate with/doesn't relate to/ > + * avoid to extend bio. So far this new field is used for bio based s/to extend/extending/ > + * pooling, we will store returning value of underlying queue's s/pooling/polling/ > + * submit_bio() here. > + */ > + unsigned int bi_private_data; > }; > > struct bvec_iter_all { > -- > 2.29.2 >