From 73c101011926c5832e6e141682180c4debe2cf45 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 8 Mar 2011 13:19:51 +0100 Subject: block: initial patch for on-stack per-task plugging This patch adds support for creating a queuing context outside of the queue itself. This enables us to batch up pieces of IO before grabbing the block device queue lock and submitting them to the IO scheduler. The context is created on the stack of the process and assigned in the task structure, so that we can auto-unplug it if we hit a schedule event. The current queue plugging happens implicitly if IO is submitted to an empty device, yet callers have to remember to unplug that IO when they are going to wait for it. This is an ugly API and has caused bugs in the past. Additionally, it requires hacks in the vm (->sync_page() callback) to handle that logic. By switching to an explicit plugging scheme we make the API a lot nicer and can get rid of the ->sync_page() hack in the vm. Signed-off-by: Jens Axboe --- kernel/exit.c | 1 + kernel/fork.c | 3 +++ kernel/sched.c | 12 ++++++++++++ 3 files changed, 16 insertions(+) (limited to 'kernel') diff --git a/kernel/exit.c b/kernel/exit.c index f9a45ebcc7b1..6a488ad2dce5 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -908,6 +908,7 @@ NORET_TYPE void do_exit(long code) profile_task_exit(tsk); WARN_ON(atomic_read(&tsk->fs_excl)); + WARN_ON(blk_needs_flush_plug(tsk)); if (unlikely(in_interrupt())) panic("Aiee, killing interrupt handler!"); diff --git a/kernel/fork.c b/kernel/fork.c index 25e429152ddc..027c80e5162f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1204,6 +1204,9 @@ static struct task_struct *copy_process(unsigned long clone_flags, * Clear TID on mm_release()? */ p->clear_child_tid = (clone_flags & CLONE_CHILD_CLEARTID) ? child_tidptr: NULL; +#ifdef CONFIG_BLOCK + p->plug = NULL; +#endif #ifdef CONFIG_FUTEX p->robust_list = NULL; #ifdef CONFIG_COMPAT diff --git a/kernel/sched.c b/kernel/sched.c index 18d38e4ec7ba..ca098bf4cc65 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3978,6 +3978,16 @@ need_resched_nonpreemptible: switch_count = &prev->nvcsw; } + /* + * If we are going to sleep and we have plugged IO queued, make + * sure to submit it to avoid deadlocks. + */ + if (prev->state != TASK_RUNNING && blk_needs_flush_plug(prev)) { + raw_spin_unlock(&rq->lock); + blk_flush_plug(prev); + raw_spin_lock(&rq->lock); + } + pre_schedule(rq, prev); if (unlikely(!rq->nr_running)) @@ -5333,6 +5343,7 @@ void __sched io_schedule(void) delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); current->in_iowait = 1; schedule(); current->in_iowait = 0; @@ -5348,6 +5359,7 @@ long __sched io_schedule_timeout(long timeout) delayacct_blkio_start(); atomic_inc(&rq->nr_iowait); + blk_flush_plug(current); current->in_iowait = 1; ret = schedule_timeout(timeout); current->in_iowait = 0; -- cgit v1.2.3 From 721a9602e6607417c6bc15b18e97a2f35266c690 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Wed, 9 Mar 2011 11:56:30 +0100 Subject: block: kill off REQ_UNPLUG With the plugging now being explicitly controlled by the submitter, callers need not pass down unplugging hints to the block layer. If they want to unplug, it's because they manually plugged on their own - in which case, they should just unplug at will. Signed-off-by: Jens Axboe --- block/blk-core.c | 2 +- drivers/block/drbd/drbd_actlog.c | 2 +- drivers/block/drbd/drbd_int.h | 2 +- drivers/block/drbd/drbd_main.c | 3 +-- drivers/block/drbd/drbd_receiver.c | 9 +-------- drivers/md/bitmap.c | 2 +- drivers/md/dm-io.c | 2 +- drivers/md/dm-kcopyd.c | 5 +---- drivers/md/md.c | 5 ++--- fs/btrfs/extent_io.c | 2 +- fs/buffer.c | 14 ++++---------- fs/direct-io.c | 2 +- fs/ext4/page-io.c | 3 +-- fs/gfs2/log.c | 4 ++-- fs/gfs2/lops.c | 12 ++++++------ fs/gfs2/meta_io.c | 2 +- fs/jbd/commit.c | 2 +- fs/jbd2/commit.c | 6 +++--- fs/nilfs2/segbuf.c | 2 +- fs/xfs/linux-2.6/xfs_aops.c | 3 +-- include/linux/blk_types.h | 2 -- include/linux/fs.h | 28 +++++++++------------------- kernel/power/block_io.c | 2 +- mm/page_io.c | 2 +- 24 files changed, 43 insertions(+), 75 deletions(-) (limited to 'kernel') diff --git a/block/blk-core.c b/block/blk-core.c index 82a45898ba76..7e9715ae18c8 100644 --- a/block/blk-core.c +++ b/block/blk-core.c @@ -1290,7 +1290,7 @@ get_rq: } plug = current->plug; - if (plug && !sync) { + if (plug) { if (!plug->should_sort && !list_empty(&plug->list)) { struct request *__rq; diff --git a/drivers/block/drbd/drbd_actlog.c b/drivers/block/drbd/drbd_actlog.c index 2096628d6e65..aca302492ff2 100644 --- a/drivers/block/drbd/drbd_actlog.c +++ b/drivers/block/drbd/drbd_actlog.c @@ -80,7 +80,7 @@ static int _drbd_md_sync_page_io(struct drbd_conf *mdev, if ((rw & WRITE) && !test_bit(MD_NO_FUA, &mdev->flags)) rw |= REQ_FUA; - rw |= REQ_UNPLUG | REQ_SYNC; + rw |= REQ_SYNC; bio = bio_alloc(GFP_NOIO, 1); bio->bi_bdev = bdev->md_bdev; diff --git a/drivers/block/drbd/drbd_int.h b/drivers/block/drbd/drbd_int.h index 0b5718e19586..b0bd27dfc1e8 100644 --- a/drivers/block/drbd/drbd_int.h +++ b/drivers/block/drbd/drbd_int.h @@ -377,7 +377,7 @@ union p_header { #define DP_HARDBARRIER 1 /* depricated */ #define DP_RW_SYNC 2 /* equals REQ_SYNC */ #define DP_MAY_SET_IN_SYNC 4 -#define DP_UNPLUG 8 /* equals REQ_UNPLUG */ +#define DP_UNPLUG 8 /* not used anymore */ #define DP_FUA 16 /* equals REQ_FUA */ #define DP_FLUSH 32 /* equals REQ_FLUSH */ #define DP_DISCARD 64 /* equals REQ_DISCARD */ diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c index 6049cb85310d..8a43ce0edeed 100644 --- a/drivers/block/drbd/drbd_main.c +++ b/drivers/block/drbd/drbd_main.c @@ -2477,12 +2477,11 @@ static u32 bio_flags_to_wire(struct drbd_conf *mdev, unsigned long bi_rw) { if (mdev->agreed_pro_version >= 95) return (bi_rw & REQ_SYNC ? DP_RW_SYNC : 0) | - (bi_rw & REQ_UNPLUG ? DP_UNPLUG : 0) | (bi_rw & REQ_FUA ? DP_FUA : 0) | (bi_rw & REQ_FLUSH ? DP_FLUSH : 0) | (bi_rw & REQ_DISCARD ? DP_DISCARD : 0); else - return bi_rw & (REQ_SYNC | REQ_UNPLUG) ? DP_RW_SYNC : 0; + return bi_rw & REQ_SYNC ? DP_RW_SYNC : 0; } /* Used to send write requests diff --git a/drivers/block/drbd/drbd_receiver.c b/drivers/block/drbd/drbd_receiver.c index 84132f8bf8a4..8e68be939deb 100644 --- a/drivers/block/drbd/drbd_receiver.c +++ b/drivers/block/drbd/drbd_receiver.c @@ -1100,8 +1100,6 @@ next_bio: /* > e->sector, unless this is the first bio */ bio->bi_sector = sector; bio->bi_bdev = mdev->ldev->backing_bdev; - /* we special case some flags in the multi-bio case, see below - * (REQ_UNPLUG) */ bio->bi_rw = rw; bio->bi_private = e; bio->bi_end_io = drbd_endio_sec; @@ -1130,10 +1128,6 @@ next_bio: bios = bios->bi_next; bio->bi_next = NULL; - /* strip off REQ_UNPLUG unless it is the last bio */ - if (bios) - bio->bi_rw &= ~REQ_UNPLUG; - drbd_generic_make_request(mdev, fault_type, bio); } while (bios); return 0; @@ -1621,12 +1615,11 @@ static unsigned long write_flags_to_bio(struct drbd_conf *mdev, u32 dpf) { if (mdev->agreed_pro_version >= 95) return (dpf & DP_RW_SYNC ? REQ_SYNC : 0) | - (dpf & DP_UNPLUG ? REQ_UNPLUG : 0) | (dpf & DP_FUA ? REQ_FUA : 0) | (dpf & DP_FLUSH ? REQ_FUA : 0) | (dpf & DP_DISCARD ? REQ_DISCARD : 0); else - return dpf & DP_RW_SYNC ? (REQ_SYNC | REQ_UNPLUG) : 0; + return dpf & DP_RW_SYNC ? REQ_SYNC : 0; } /* mirrored write */ diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c index 54bfc274b39a..ca203cb23f3c 100644 --- a/drivers/md/bitmap.c +++ b/drivers/md/bitmap.c @@ -347,7 +347,7 @@ static void write_page(struct bitmap *bitmap, struct page *page, int wait) atomic_inc(&bitmap->pending_writes); set_buffer_locked(bh); set_buffer_mapped(bh); - submit_bh(WRITE | REQ_UNPLUG | REQ_SYNC, bh); + submit_bh(WRITE | REQ_SYNC, bh); bh = bh->b_this_page; } diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c index 136d4f71a116..76a5af00a26b 100644 --- a/drivers/md/dm-io.c +++ b/drivers/md/dm-io.c @@ -352,7 +352,7 @@ static void dispatch_io(int rw, unsigned int num_regions, BUG_ON(num_regions > DM_IO_MAX_REGIONS); if (sync) - rw |= REQ_SYNC | REQ_UNPLUG; + rw |= REQ_SYNC; /* * For multiple regions we need to be careful to rewind diff --git a/drivers/md/dm-kcopyd.c b/drivers/md/dm-kcopyd.c index 400cf35094a4..1bb73a13ca40 100644 --- a/drivers/md/dm-kcopyd.c +++ b/drivers/md/dm-kcopyd.c @@ -356,11 +356,8 @@ static int run_io_job(struct kcopyd_job *job) if (job->rw == READ) r = dm_io(&io_req, 1, &job->source, NULL); - else { - if (job->num_dests > 1) - io_req.bi_rw |= REQ_UNPLUG; + else r = dm_io(&io_req, job->num_dests, job->dests, NULL); - } return r; } diff --git a/drivers/md/md.c b/drivers/md/md.c index ca0d79c264b9..28f9c1ee4e3a 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -777,8 +777,7 @@ void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, bio->bi_end_io = super_written; atomic_inc(&mddev->pending_writes); - submit_bio(REQ_WRITE | REQ_SYNC | REQ_UNPLUG | REQ_FLUSH | REQ_FUA, - bio); + submit_bio(REQ_WRITE | REQ_SYNC | REQ_FLUSH | REQ_FUA, bio); } void md_super_wait(mddev_t *mddev) @@ -806,7 +805,7 @@ int sync_page_io(mdk_rdev_t *rdev, sector_t sector, int size, struct completion event; int ret; - rw |= REQ_SYNC | REQ_UNPLUG; + rw |= REQ_SYNC; bio->bi_bdev = (metadata_op && rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev; diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 92ac5192c518..b76f7cd47401 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -2182,7 +2182,7 @@ static int __extent_writepage(struct page *page, struct writeback_control *wbc, unsigned long nr_written = 0; if (wbc->sync_mode == WB_SYNC_ALL) - write_flags = WRITE_SYNC_PLUG; + write_flags = WRITE_SYNC; else write_flags = WRITE; diff --git a/fs/buffer.c b/fs/buffer.c index f903f2e5b4fe..42534f67d71b 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -767,7 +767,7 @@ static int fsync_buffers_list(spinlock_t *lock, struct list_head *list) * still in flight on potentially older * contents. */ - write_dirty_buffer(bh, WRITE_SYNC_PLUG); + write_dirty_buffer(bh, WRITE_SYNC); /* * Kick off IO for the previous mapping. Note @@ -1602,14 +1602,8 @@ EXPORT_SYMBOL(unmap_underlying_metadata); * prevents this contention from occurring. * * If block_write_full_page() is called with wbc->sync_mode == - * WB_SYNC_ALL, the writes are posted using WRITE_SYNC_PLUG; this - * causes the writes to be flagged as synchronous writes, but the - * block device queue will NOT be unplugged, since usually many pages - * will be pushed to the out before the higher-level caller actually - * waits for the writes to be completed. The various wait functions, - * such as wait_on_writeback_range() will ultimately call sync_page() - * which will ultimately call blk_run_backing_dev(), which will end up - * unplugging the device queue. + * WB_SYNC_ALL, the writes are posted using WRITE_SYNC; this + * causes the writes to be flagged as synchronous writes. */ static int __block_write_full_page(struct inode *inode, struct page *page, get_block_t *get_block, struct writeback_control *wbc, @@ -1622,7 +1616,7 @@ static int __block_write_full_page(struct inode *inode, struct page *page, const unsigned blocksize = 1 << inode->i_blkbits; int nr_underway = 0; int write_op = (wbc->sync_mode == WB_SYNC_ALL ? - WRITE_SYNC_PLUG : WRITE); + WRITE_SYNC : WRITE); BUG_ON(!PageLocked(page)); diff --git a/fs/direct-io.c b/fs/direct-io.c index df709b3b860a..426083136099 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -1173,7 +1173,7 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, struct dio *dio; if (rw & WRITE) - rw = WRITE_ODIRECT_PLUG; + rw = WRITE_ODIRECT; if (bdev) bdev_blkbits = blksize_bits(bdev_logical_block_size(bdev)); diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index 955cc309142f..e2cd90e4bb7c 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -310,8 +310,7 @@ static int io_submit_init(struct ext4_io_submit *io, io_end->offset = (page->index << PAGE_CACHE_SHIFT) + bh_offset(bh); io->io_bio = bio; - io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? - WRITE_SYNC_PLUG : WRITE); + io->io_op = (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); io->io_next_block = bh->b_blocknr; return 0; } diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index eb01f3575e10..7f1c11202342 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -121,7 +121,7 @@ __acquires(&sdp->sd_log_lock) lock_buffer(bh); if (test_clear_buffer_dirty(bh)) { bh->b_end_io = end_buffer_write_sync; - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); } else { unlock_buffer(bh); brelse(bh); @@ -647,7 +647,7 @@ static void gfs2_ordered_write(struct gfs2_sbd *sdp) lock_buffer(bh); if (buffer_mapped(bh) && test_clear_buffer_dirty(bh)) { bh->b_end_io = end_buffer_write_sync; - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); } else { unlock_buffer(bh); brelse(bh); diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index bf33f822058d..48b545a1979a 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -200,7 +200,7 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp) } gfs2_log_unlock(sdp); - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); n = 0; @@ -210,7 +210,7 @@ static void buf_lo_before_commit(struct gfs2_sbd *sdp) gfs2_log_unlock(sdp); lock_buffer(bd2->bd_bh); bh = gfs2_log_fake_buf(sdp, bd2->bd_bh); - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); if (++n >= num) break; @@ -352,7 +352,7 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp) sdp->sd_log_num_revoke--; if (offset + sizeof(u64) > sdp->sd_sb.sb_bsize) { - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); bh = gfs2_log_get_buf(sdp); mh = (struct gfs2_meta_header *)bh->b_data; @@ -369,7 +369,7 @@ static void revoke_lo_before_commit(struct gfs2_sbd *sdp) } gfs2_assert_withdraw(sdp, !sdp->sd_log_num_revoke); - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); } static void revoke_lo_before_scan(struct gfs2_jdesc *jd, @@ -571,7 +571,7 @@ static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh, ptr = bh_log_ptr(bh); get_bh(bh); - submit_bh(WRITE_SYNC_PLUG, bh); + submit_bh(WRITE_SYNC, bh); gfs2_log_lock(sdp); while(!list_empty(list)) { bd = list_entry(list->next, struct gfs2_bufdata, bd_le.le_list); @@ -597,7 +597,7 @@ static void gfs2_write_blocks(struct gfs2_sbd *sdp, struct buffer_head *bh, } else { bh1 = gfs2_log_fake_buf(sdp, bd->bd_bh); } - submit_bh(WRITE_SYNC_PLUG, bh1); + submit_bh(WRITE_SYNC, bh1); gfs2_log_lock(sdp); ptr += 2; } diff --git a/fs/gfs2/meta_io.c b/fs/gfs2/meta_io.c index a566331db4e1..867b713cba92 100644 --- a/fs/gfs2/meta_io.c +++ b/fs/gfs2/meta_io.c @@ -37,7 +37,7 @@ static int gfs2_aspace_writepage(struct page *page, struct writeback_control *wb struct buffer_head *bh, *head; int nr_underway = 0; int write_op = REQ_META | - (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC_PLUG : WRITE); + (wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE); BUG_ON(!PageLocked(page)); BUG_ON(!page_has_buffers(page)); diff --git a/fs/jbd/commit.c b/fs/jbd/commit.c index 34a4861c14b8..66be299acb1b 100644 --- a/fs/jbd/commit.c +++ b/fs/jbd/commit.c @@ -333,7 +333,7 @@ void journal_commit_transaction(journal_t *journal) * instead we rely on sync_buffer() doing the unplug for us. */ if (commit_transaction->t_synchronous_commit) - write_op = WRITE_SYNC_PLUG; + write_op = WRITE_SYNC; spin_lock(&commit_transaction->t_handle_lock); while (commit_transaction->t_updates) { DEFINE_WAIT(wait); diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index f3ad1598b201..3da1cc4346d5 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -137,9 +137,9 @@ static int journal_submit_commit_record(journal_t *journal, if (journal->j_flags & JBD2_BARRIER && !JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT)) - ret = submit_bh(WRITE_SYNC_PLUG | WRITE_FLUSH_FUA, bh); + ret = submit_bh(WRITE_SYNC | WRITE_FLUSH_FUA, bh); else - ret = submit_bh(WRITE_SYNC_PLUG, bh); + ret = submit_bh(WRITE_SYNC, bh); *cbh = bh; return ret; @@ -369,7 +369,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) * instead we rely on sync_buffer() doing the unplug for us. */ if (commit_transaction->t_synchronous_commit) - write_op = WRITE_SYNC_PLUG; + write_op = WRITE_SYNC; trace_jbd2_commit_locking(journal, commit_transaction); stats.run.rs_wait = commit_transaction->t_max_wait; stats.run.rs_locked = jiffies; diff --git a/fs/nilfs2/segbuf.c b/fs/nilfs2/segbuf.c index 0f83e93935b2..2853ff20f85a 100644 --- a/fs/nilfs2/segbuf.c +++ b/fs/nilfs2/segbuf.c @@ -509,7 +509,7 @@ static int nilfs_segbuf_write(struct nilfs_segment_buffer *segbuf, * Last BIO is always sent through the following * submission. */ - rw |= REQ_SYNC | REQ_UNPLUG; + rw |= REQ_SYNC; res = nilfs_segbuf_submit_bio(segbuf, &wi, rw); } diff --git a/fs/xfs/linux-2.6/xfs_aops.c b/fs/xfs/linux-2.6/xfs_aops.c index 83c1c20d145a..6bbb0ee33253 100644 --- a/fs/xfs/linux-2.6/xfs_aops.c +++ b/fs/xfs/linux-2.6/xfs_aops.c @@ -413,8 +413,7 @@ xfs_submit_ioend_bio( if (xfs_ioend_new_eof(ioend)) xfs_mark_inode_dirty(XFS_I(ioend->io_inode)); - submit_bio(wbc->sync_mode == WB_SYNC_ALL ? - WRITE_SYNC_PLUG : WRITE, bio); + submit_bio(wbc->sync_mode == WB_SYNC_ALL ? WRITE_SYNC : WRITE, bio); } STATIC struct bio * diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h index 16b286473042..be50d9e70a7d 100644 --- a/include/linux/blk_types.h +++ b/include/linux/blk_types.h @@ -128,7 +128,6 @@ enum rq_flag_bits { __REQ_NOIDLE, /* don't anticipate more IO after this one */ /* bio only flags */ - __REQ_UNPLUG, /* unplug the immediately after submission */ __REQ_RAHEAD, /* read ahead, can fail anytime */ __REQ_THROTTLED, /* This bio has already been subjected to * throttling rules. Don't do it again. */ @@ -172,7 +171,6 @@ enum rq_flag_bits { REQ_NOIDLE | REQ_FLUSH | REQ_FUA) #define REQ_CLONE_MASK REQ_COMMON_MASK -#define REQ_UNPLUG (1 << __REQ_UNPLUG) #define REQ_RAHEAD (1 << __REQ_RAHEAD) #define REQ_THROTTLED (1 << __REQ_THROTTLED) diff --git a/include/linux/fs.h b/include/linux/fs.h index 9f2cf69911b8..543e226ea6a3 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -135,16 +135,10 @@ struct inodes_stat_t { * block layer could (in theory) choose to ignore this * request if it runs into resource problems. * WRITE A normal async write. Device will be plugged. - * WRITE_SYNC_PLUG Synchronous write. Identical to WRITE, but passes down + * WRITE_SYNC Synchronous write. Identical to WRITE, but passes down * the hint that someone will be waiting on this IO - * shortly. The device must still be unplugged explicitly, - * WRITE_SYNC_PLUG does not do this as we could be - * submitting more writes before we actually wait on any - * of them. - * WRITE_SYNC Like WRITE_SYNC_PLUG, but also unplugs the device - * immediately after submission. The write equivalent - * of READ_SYNC. - * WRITE_ODIRECT_PLUG Special case write for O_DIRECT only. + * shortly. The write equivalent of READ_SYNC. + * WRITE_ODIRECT Special case write for O_DIRECT only. * WRITE_FLUSH Like WRITE_SYNC but with preceding cache flush. * WRITE_FUA Like WRITE_SYNC but data is guaranteed to be on * non-volatile media on completion. @@ -160,18 +154,14 @@ struct inodes_stat_t { #define WRITE RW_MASK #define READA RWA_MASK -#define READ_SYNC (READ | REQ_SYNC | REQ_UNPLUG) +#define READ_SYNC (READ | REQ_SYNC) #define READ_META (READ | REQ_META) -#define WRITE_SYNC_PLUG (WRITE | REQ_SYNC | REQ_NOIDLE) -#define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG) -#define WRITE_ODIRECT_PLUG (WRITE | REQ_SYNC) +#define WRITE_SYNC (WRITE | REQ_SYNC | REQ_NOIDLE) +#define WRITE_ODIRECT (WRITE | REQ_SYNC) #define WRITE_META (WRITE | REQ_META) -#define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ - REQ_FLUSH) -#define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ - REQ_FUA) -#define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_UNPLUG | \ - REQ_FLUSH | REQ_FUA) +#define WRITE_FLUSH (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH) +#define WRITE_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FUA) +#define WRITE_FLUSH_FUA (WRITE | REQ_SYNC | REQ_NOIDLE | REQ_FLUSH | REQ_FUA) #define SEL_IN 1 #define SEL_OUT 2 diff --git a/kernel/power/block_io.c b/kernel/power/block_io.c index 83bbc7c02df9..d09dd10c5a5e 100644 --- a/kernel/power/block_io.c +++ b/kernel/power/block_io.c @@ -28,7 +28,7 @@ static int submit(int rw, struct block_device *bdev, sector_t sector, struct page *page, struct bio **bio_chain) { - const int bio_rw = rw | REQ_SYNC | REQ_UNPLUG; + const int bio_rw = rw | REQ_SYNC; struct bio *bio; bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); diff --git a/mm/page_io.c b/mm/page_io.c index 2dee975bf469..dc76b4d0611e 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -106,7 +106,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc) goto out; } if (wbc->sync_mode == WB_SYNC_ALL) - rw |= REQ_SYNC | REQ_UNPLUG; + rw |= REQ_SYNC; count_vm_event(PSWPOUT); set_page_writeback(page); unlock_page(page); -- cgit v1.2.3