From 30fad952ad8a17930262c23983169c1c1d0c7bbe Mon Sep 17 00:00:00 2001 From: Liu Bo Date: Mon, 21 Aug 2017 15:49:59 -0600 Subject: [PATCH] Btrfs: make plug in writing meta blocks really work We have started plug in btrfs_write_and_wait_marked_extents() but the generated IOs actually go to device's schedule IO list where the work is doing in another task, thus the started plug doesn't make any sense. And since we wait for IOs immediately after writing meta blocks, it's the same case as writing log tree, doing sync submit can merge more IOs. Signed-off-by: Liu Bo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/disk-io.c | 6 ++++-- fs/btrfs/transaction.c | 2 ++ 2 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 0a98567f8cfc7..23442747363ed 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1005,8 +1005,10 @@ static blk_status_t __btree_submit_bio_done(void *private_data, struct bio *bio, return ret; } -static int check_async_write(unsigned long bio_flags) +static int check_async_write(struct btrfs_inode *bi, unsigned long bio_flags) { + if (atomic_read(&bi->sync_writers)) + return 0; if (bio_flags & EXTENT_BIO_TREE_LOG) return 0; #ifdef CONFIG_X86 @@ -1022,7 +1024,7 @@ static blk_status_t btree_submit_bio_hook(void *private_data, struct bio *bio, { struct inode *inode = private_data; struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb); - int async = check_async_write(bio_flags); + int async = check_async_write(BTRFS_I(inode), bio_flags); blk_status_t ret; if (bio_op(bio) != REQ_OP_WRITE) { diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index f615d59b0489e..9c5f126064bde 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -950,6 +950,7 @@ int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, u64 start = 0; u64 end; + atomic_inc(&BTRFS_I(fs_info->btree_inode)->sync_writers); while (!find_first_extent_bit(dirty_pages, start, &start, &end, mark, &cached_state)) { bool wait_writeback = false; @@ -985,6 +986,7 @@ int btrfs_write_marked_extents(struct btrfs_fs_info *fs_info, cond_resched(); start = end + 1; } + atomic_dec(&BTRFS_I(fs_info->btree_inode)->sync_writers); return werr; } -- 2.39.5