From 9f203507ed277ee86e3f76a15e09db1c92e40b94 Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Sat, 20 Apr 2013 15:46:17 -0400 Subject: [PATCH] ext4: mark all metadata I/O with REQ_META As Dave Chinner pointed out at the 2013 LSF/MM workshop, it's important that metadata I/O requests are marked as such to avoid priority inversions caused by I/O bandwidth throttling. Signed-off-by: "Theodore Ts'o" --- fs/ext4/balloc.c | 2 +- fs/ext4/ialloc.c | 2 +- fs/ext4/mmp.c | 4 ++-- fs/ext4/super.c | 2 +- 4 files changed, 5 insertions(+), 5 deletions(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 8dcaea6..d0f13ea 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -441,7 +441,7 @@ ext4_read_block_bitmap_nowait(struct super_block *sb, ext4_group_t block_group) trace_ext4_read_block_bitmap_load(sb, block_group); bh->b_end_io = ext4_end_bitmap_read; get_bh(bh); - submit_bh(READ, bh); + submit_bh(READ | REQ_META | REQ_PRIO, bh); return bh; verify: ext4_validate_block_bitmap(sb, desc, block_group, bh); diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 18d36d8..00a818d 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -166,7 +166,7 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) trace_ext4_load_inode_bitmap(sb, block_group); bh->b_end_io = ext4_end_bitmap_read; get_bh(bh); - submit_bh(READ, bh); + submit_bh(READ | REQ_META | REQ_PRIO, bh); wait_on_buffer(bh); if (!buffer_uptodate(bh)) { put_bh(bh); diff --git a/fs/ext4/mmp.c b/fs/ext4/mmp.c index b3b1f7d..214461e 100644 --- a/fs/ext4/mmp.c +++ b/fs/ext4/mmp.c @@ -54,7 +54,7 @@ static int write_mmp_block(struct super_block *sb, struct buffer_head *bh) lock_buffer(bh); bh->b_end_io = end_buffer_write_sync; get_bh(bh); - submit_bh(WRITE_SYNC, bh); + submit_bh(WRITE_SYNC | REQ_META | REQ_PRIO, bh); wait_on_buffer(bh); sb_end_write(sb); if (unlikely(!buffer_uptodate(bh))) @@ -86,7 +86,7 @@ static int read_mmp_block(struct super_block *sb, struct buffer_head **bh, get_bh(*bh); lock_buffer(*bh); (*bh)->b_end_io = end_buffer_read_sync; - submit_bh(READ_SYNC, *bh); + submit_bh(READ_SYNC | REQ_META | REQ_PRIO, *bh); wait_on_buffer(*bh); if (!buffer_uptodate(*bh)) { brelse(*bh); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index bfa29ec..dbc7c09 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -4252,7 +4252,7 @@ static journal_t *ext4_get_dev_journal(struct super_block *sb, goto out_bdev; } journal->j_private = sb; - ll_rw_block(READ, 1, &journal->j_sb_buffer); + ll_rw_block(READ | REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer); wait_on_buffer(journal->j_sb_buffer); if (!buffer_uptodate(journal->j_sb_buffer)) { ext4_msg(sb, KERN_ERR, "I/O error on journal device"); -- 2.7.4