From patchwork Fri Feb 15 11:13:18 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ming Lei X-Patchwork-Id: 10814689 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3EE5413B5 for ; Fri, 15 Feb 2019 11:16:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 368162EAE8 for ; Fri, 15 Feb 2019 11:16:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 291932EE6D; Fri, 15 Feb 2019 11:16:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D42F52EAE8 for ; Fri, 15 Feb 2019 11:16:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2436475AbfBOLQd (ORCPT ); Fri, 15 Feb 2019 06:16:33 -0500 Received: from mx1.redhat.com ([209.132.183.28]:2904 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732023AbfBOLQX (ORCPT ); Fri, 15 Feb 2019 06:16:23 -0500 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 mx1.redhat.com (Postfix) with ESMTPS id 5204DC7857; Fri, 15 Feb 2019 11:16:22 +0000 (UTC) Received: from localhost (ovpn-8-22.pek2.redhat.com [10.72.8.22]) by smtp.corp.redhat.com (Postfix) with ESMTP id 38D6A26E74; Fri, 15 Feb 2019 11:16:20 +0000 (UTC) From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Theodore Ts'o , Omar Sandoval , Sagi Grimberg , Dave Chinner , Kent Overstreet , Mike Snitzer , dm-devel@redhat.com, Alexander Viro , linux-fsdevel@vger.kernel.org, linux-raid@vger.kernel.org, David Sterba , linux-btrfs@vger.kernel.org, "Darrick J . Wong" , linux-xfs@vger.kernel.org, Gao Xiang , Christoph Hellwig , linux-ext4@vger.kernel.org, Coly Li , linux-bcache@vger.kernel.org, Boaz Harrosh , Bob Peterson , cluster-devel@redhat.com, Ming Lei Subject: [PATCH V15 12/18] bcache: avoid to use bio_for_each_segment_all() in bch_bio_alloc_pages() Date: Fri, 15 Feb 2019 19:13:18 +0800 Message-Id: <20190215111324.30129-13-ming.lei@redhat.com> In-Reply-To: <20190215111324.30129-1-ming.lei@redhat.com> References: <20190215111324.30129-1-ming.lei@redhat.com> X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 15 Feb 2019 11:16:23 +0000 (UTC) Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP bch_bio_alloc_pages() is always called on one new bio, so it is safe to access the bvec table directly. Given it is the only kind of this case, open code the bvec table access since bio_for_each_segment_all() will be changed to support for iterating over multipage bvec. Acked-by: Coly Li Reviewed-by: Omar Sandoval Reviewed-by: Christoph Hellwig Signed-off-by: Ming Lei --- drivers/md/bcache/util.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/util.c b/drivers/md/bcache/util.c index 20eddeac1531..62fb917f7a4f 100644 --- a/drivers/md/bcache/util.c +++ b/drivers/md/bcache/util.c @@ -270,7 +270,11 @@ int bch_bio_alloc_pages(struct bio *bio, gfp_t gfp_mask) int i; struct bio_vec *bv; - bio_for_each_segment_all(bv, bio, i) { + /* + * This is called on freshly new bio, so it is safe to access the + * bvec table directly. + */ + for (i = 0, bv = bio->bi_io_vec; i < bio->bi_vcnt; bv++, i++) { bv->bv_page = alloc_page(gfp_mask); if (!bv->bv_page) { while (--bv >= bio->bi_io_vec)