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=-16.0 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 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 0970AC433E0 for ; Tue, 23 Mar 2021 11:30:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BE1E3619C0 for ; Tue, 23 Mar 2021 11:30:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230492AbhCWL3t (ORCPT ); Tue, 23 Mar 2021 07:29:49 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:45572 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229728AbhCWL3l (ORCPT ); Tue, 23 Mar 2021 07:29:41 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1616498980; 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=OcLqJ54i9XylFCC6CIDnOKsaauV5bJuF0aAmd3uf7lw=; b=F2hD0X0t1a17DJozsufvibJy/Eo18TKx3frhAd0IzvOKvkkfEMhcFE2X9xERjED7Zt9Juk NI8WrWnSOSOkQkbtEp4fIVALSBgRznh5Wb3UtB4ce+YUOw0LIzNmbzY5COwj6bNLwcHrXC RvY3Fm0Y8+2p6sCc4x8vV/G2wWE3PLA= 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-535-LNksVTdXOBe-rwNCkTxneg-1; Tue, 23 Mar 2021 07:29:36 -0400 X-MC-Unique: LNksVTdXOBe-rwNCkTxneg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 74A0F1083E82; Tue, 23 Mar 2021 11:29:35 +0000 (UTC) Received: from T590 (ovpn-13-171.pek2.redhat.com [10.72.13.171]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 19B9A5FCBE; Tue, 23 Mar 2021 11:29:23 +0000 (UTC) Date: Tue, 23 Mar 2021 19:29:18 +0800 From: Ming Lei To: Mike Snitzer 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: References: <20210318164827.1481133-1-ming.lei@redhat.com> <20210318164827.1481133-7-ming.lei@redhat.com> <20210319174422.GD9938@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210319174422.GD9938@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Fri, Mar 19, 2021 at 01:44:22PM -0400, Mike Snitzer wrote: > 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/ > Good catch, will fix all in V3. -- Ming