Return-Path: Received: from mx1.redhat.com ([209.132.183.28]:41854 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728719AbeKOTDi (ORCPT ); Thu, 15 Nov 2018 14:03:38 -0500 From: Ming Lei To: Jens Axboe Cc: linux-block@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Ming Lei , Dave Chinner , Kent Overstreet , Mike Snitzer , dm-devel@redhat.com, Alexander Viro , linux-fsdevel@vger.kernel.org, Shaohua Li , linux-raid@vger.kernel.org, linux-erofs@lists.ozlabs.org, David Sterba , linux-btrfs@vger.kernel.org, "Darrick J . Wong" , linux-xfs@vger.kernel.org, Gao Xiang , Christoph Hellwig , Theodore Ts'o , linux-ext4@vger.kernel.org, Coly Li , linux-bcache@vger.kernel.org, Boaz Harrosh , Bob Peterson , cluster-devel@redhat.com Subject: [PATCH V10 13/19] iomap & xfs: only account for new added page Date: Thu, 15 Nov 2018 16:53:00 +0800 Message-Id: <20181115085306.9910-14-ming.lei@redhat.com> In-Reply-To: <20181115085306.9910-1-ming.lei@redhat.com> References: <20181115085306.9910-1-ming.lei@redhat.com> Sender: linux-ext4-owner@vger.kernel.org List-ID: After multi-page is enabled, one new page may be merged to a segment even though it is a new added page. This patch deals with this issue by post-check in case of merge, and only a freshly new added page need to be dealt with for iomap & xfs. Cc: Dave Chinner Cc: Kent Overstreet Cc: Mike Snitzer Cc: dm-devel@redhat.com Cc: Alexander Viro Cc: linux-fsdevel@vger.kernel.org Cc: Shaohua Li Cc: linux-raid@vger.kernel.org Cc: linux-erofs@lists.ozlabs.org Cc: David Sterba Cc: linux-btrfs@vger.kernel.org Cc: Darrick J. Wong Cc: linux-xfs@vger.kernel.org Cc: Gao Xiang Cc: Christoph Hellwig Cc: Theodore Ts'o Cc: linux-ext4@vger.kernel.org Cc: Coly Li Cc: linux-bcache@vger.kernel.org Cc: Boaz Harrosh Cc: Bob Peterson Cc: cluster-devel@redhat.com Signed-off-by: Ming Lei --- fs/iomap.c | 22 ++++++++++++++-------- fs/xfs/xfs_aops.c | 10 ++++++++-- include/linux/bio.h | 11 +++++++++++ 3 files changed, 33 insertions(+), 10 deletions(-) diff --git a/fs/iomap.c b/fs/iomap.c index df0212560b36..a1b97a5c726a 100644 --- a/fs/iomap.c +++ b/fs/iomap.c @@ -288,6 +288,7 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, loff_t orig_pos = pos; unsigned poff, plen; sector_t sector; + bool need_account = false; if (iomap->type == IOMAP_INLINE) { WARN_ON_ONCE(pos); @@ -313,18 +314,15 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, */ sector = iomap_sector(iomap, pos); if (ctx->bio && bio_end_sector(ctx->bio) == sector) { - if (__bio_try_merge_page(ctx->bio, page, plen, poff)) + if (__bio_try_merge_page(ctx->bio, page, plen, poff)) { + need_account = iop && bio_is_last_segment(ctx->bio, + page, plen, poff); goto done; + } is_contig = true; } - /* - * If we start a new segment we need to increase the read count, and we - * need to do so before submitting any previous full bio to make sure - * that we don't prematurely unlock the page. - */ - if (iop) - atomic_inc(&iop->read_count); + need_account = true; if (!ctx->bio || !is_contig || bio_full(ctx->bio)) { gfp_t gfp = mapping_gfp_constraint(page->mapping, GFP_KERNEL); @@ -347,6 +345,14 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, __bio_add_page(ctx->bio, page, plen, poff); done: /* + * If we add a new page we need to increase the read count, and we + * need to do so before submitting any previous full bio to make sure + * that we don't prematurely unlock the page. + */ + if (iop && need_account) + atomic_inc(&iop->read_count); + + /* * Move the caller beyond our range so that it keeps making progress. * For that we have to include any leading non-uptodate ranges, but * we can skip trailing ones as they will be handled in the next diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 1f1829e506e8..d8e9cc9f751a 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -603,6 +603,7 @@ xfs_add_to_ioend( unsigned len = i_blocksize(inode); unsigned poff = offset & (PAGE_SIZE - 1); sector_t sector; + bool need_account; sector = xfs_fsb_to_db(ip, wpc->imap.br_startblock) + ((offset - XFS_FSB_TO_B(mp, wpc->imap.br_startoff)) >> 9); @@ -617,13 +618,18 @@ xfs_add_to_ioend( } if (!__bio_try_merge_page(wpc->ioend->io_bio, page, len, poff)) { - if (iop) - atomic_inc(&iop->write_count); + need_account = true; if (bio_full(wpc->ioend->io_bio)) xfs_chain_bio(wpc->ioend, wbc, bdev, sector); __bio_add_page(wpc->ioend->io_bio, page, len, poff); + } else { + need_account = iop && bio_is_last_segment(wpc->ioend->io_bio, + page, len, poff); } + if (iop && need_account) + atomic_inc(&iop->write_count); + wpc->ioend->io_size += len; } diff --git a/include/linux/bio.h b/include/linux/bio.h index 1a2430a8b89d..5040e9a2eb09 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -341,6 +341,17 @@ static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) return &bio->bi_io_vec[bio->bi_vcnt - 1]; } +/* iomap needs this helper to deal with sub-pagesize bvec */ +static inline bool bio_is_last_segment(struct bio *bio, struct page *page, + unsigned int len, unsigned int off) +{ + struct bio_vec bv; + + bvec_last_segment(bio_last_bvec_all(bio), &bv); + + return bv.bv_page == page && bv.bv_len == len && bv.bv_offset == off; +} + enum bip_flags { BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ -- 2.9.5