Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752133AbdFZMZf (ORCPT ); Mon, 26 Jun 2017 08:25:35 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48444 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751920AbdFZMSi (ORCPT ); Mon, 26 Jun 2017 08:18:38 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 6E95A80F90 Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=ming.lei@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 6E95A80F90 From: Ming Lei To: Jens Axboe , Christoph Hellwig , Huang Ying , Andrew Morton , Alexander Viro Cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, Ming Lei Subject: [PATCH v2 33/51] block: deal with dirtying pages for multipage bvec Date: Mon, 26 Jun 2017 20:10:16 +0800 Message-Id: <20170626121034.3051-34-ming.lei@redhat.com> In-Reply-To: <20170626121034.3051-1-ming.lei@redhat.com> References: <20170626121034.3051-1-ming.lei@redhat.com> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 26 Jun 2017 12:18:27 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2568 Lines: 104 In bio_check_pages_dirty(), bvec->bv_page is used as flag for marking if the page has been dirtied & released, and if no, it will be dirtied in deferred workqueue. With multipage bvec, we can't do that any more, so change the logic into checking all pages in one mp bvec, and only release all these pages if all are dirtied, otherwise dirty them all in deferred wrokqueue. Signed-off-by: Ming Lei --- block/bio.c | 45 +++++++++++++++++++++++++++++++++++++-------- 1 file changed, 37 insertions(+), 8 deletions(-) diff --git a/block/bio.c b/block/bio.c index bf7f25889f6e..22e5deec7ec7 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1641,8 +1641,9 @@ void bio_set_pages_dirty(struct bio *bio) { struct bio_vec *bvec; int i; + struct bvec_iter_all bia; - bio_for_each_segment_all(bvec, bio, i) { + bio_for_each_segment_all_sp(bvec, bio, i, bia) { struct page *page = bvec->bv_page; if (page && !PageCompound(page)) @@ -1650,16 +1651,26 @@ void bio_set_pages_dirty(struct bio *bio) } } +static inline void release_mp_bvec_pages(struct bio_vec *bvec) +{ + struct bio_vec bv; + struct bvec_iter iter; + + bvec_for_each_sp_bvec(bv, bvec, iter) + put_page(bv.bv_page); +} + static void bio_release_pages(struct bio *bio) { struct bio_vec *bvec; int i; - bio_for_each_segment_all(bvec, bio, i) { + /* iterate each mp bvec */ + bio_for_each_segment_all_mp(bvec, bio, i) { struct page *page = bvec->bv_page; if (page) - put_page(page); + release_mp_bvec_pages(bvec); } } @@ -1703,20 +1714,38 @@ static void bio_dirty_fn(struct work_struct *work) } } +static inline void check_mp_bvec_pages(struct bio_vec *bvec, + int *nr_dirty, int *nr_pages) +{ + struct bio_vec bv; + struct bvec_iter iter; + + bvec_for_each_sp_bvec(bv, bvec, iter) { + struct page *page = bv.bv_page; + + if (PageDirty(page) || PageCompound(page)) + (*nr_dirty)++; + (*nr_pages)++; + } +} + void bio_check_pages_dirty(struct bio *bio) { struct bio_vec *bvec; int nr_clean_pages = 0; int i; - bio_for_each_segment_all(bvec, bio, i) { - struct page *page = bvec->bv_page; + bio_for_each_segment_all_mp(bvec, bio, i) { + int nr_dirty = 0, nr_pages = 0; + + check_mp_bvec_pages(bvec, &nr_dirty, &nr_pages); - if (PageDirty(page) || PageCompound(page)) { - put_page(page); + /* release all pages in the mp bvec if all are dirtied */ + if (nr_dirty == nr_pages) { + release_mp_bvec_pages(bvec); bvec->bv_page = NULL; } else { - nr_clean_pages++; + nr_clean_pages += nr_pages; } } -- 2.9.4