| Message ID | 7f579ef2f4d4ab38577bd9768f4e38ac4d00fc48.1661921714.git.naohiro.aota@wdc.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | btrfs: zoned: fix API misuse of zone finish waiting | expand |
On Wed, Aug 31, 2022 at 01:55:48PM +0900, Naohiro Aota wrote: > The commit 2ce543f47843 ("btrfs: zoned: wait until zone is finished when > allocation didn't progress") implemented a zone finish waiting mechanism to > the write path of zoned mode. However, using wait_var_event()/wake_up_all() > on fs_info->zone_finish_wait is wrong and wait_var_event() just hangs > because no one ever wakes it up once it goes into sleep. > > Indeed, we can simply use wait_on_bit_io() and clear_and_wake_up_bit() on > fs_info->flags with a proper barrier installed. > > Fixes: 2ce543f47843 ("btrfs: zoned: wait until zone is finished when allocation didn't progress") > Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> Added to misc-next, thanks.
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 0069bc86c04f..5d03fc267b58 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1089,8 +1089,6 @@ struct btrfs_fs_info { spinlock_t zone_active_bgs_lock; struct list_head zone_active_bgs; - /* Waiters when BTRFS_FS_NEED_ZONE_FINISH is set */ - wait_queue_head_t zone_finish_wait; /* Updates are not protected by any lock */ struct btrfs_commit_stats commit_stats; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 912e0b2bd0c5..b5470ac2db5b 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3079,7 +3079,6 @@ void btrfs_init_fs_info(struct btrfs_fs_info *fs_info) init_waitqueue_head(&fs_info->transaction_blocked_wait); init_waitqueue_head(&fs_info->async_submit_wait); init_waitqueue_head(&fs_info->delayed_iputs_wait); - init_waitqueue_head(&fs_info->zone_finish_wait); /* Usable values until the real ones are cached from the superblock */ fs_info->nodesize = 4096; diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index b9d40e25d978..e5284f2686c8 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1644,10 +1644,9 @@ static noinline int run_delalloc_zoned(struct btrfs_inode *inode, done_offset = end; if (done_offset == start) { - struct btrfs_fs_info *info = inode->root->fs_info; - - wait_var_event(&info->zone_finish_wait, - !test_bit(BTRFS_FS_NEED_ZONE_FINISH, &info->flags)); + wait_on_bit_io(&inode->root->fs_info->flags, + BTRFS_FS_NEED_ZONE_FINISH, + TASK_UNINTERRUPTIBLE); continue; } diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index dc96b3331bfb..9c6a8c38c67e 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -2010,8 +2010,7 @@ static int do_zone_finish(struct btrfs_block_group *block_group, bool fully_writ /* For active_bg_list */ btrfs_put_block_group(block_group); - clear_bit(BTRFS_FS_NEED_ZONE_FINISH, &fs_info->flags); - wake_up_all(&fs_info->zone_finish_wait); + clear_and_wake_up_bit(BTRFS_FS_NEED_ZONE_FINISH, &fs_info->flags); return 0; }
The commit 2ce543f47843 ("btrfs: zoned: wait until zone is finished when allocation didn't progress") implemented a zone finish waiting mechanism to the write path of zoned mode. However, using wait_var_event()/wake_up_all() on fs_info->zone_finish_wait is wrong and wait_var_event() just hangs because no one ever wakes it up once it goes into sleep. Indeed, we can simply use wait_on_bit_io() and clear_and_wake_up_bit() on fs_info->flags with a proper barrier installed. Fixes: 2ce543f47843 ("btrfs: zoned: wait until zone is finished when allocation didn't progress") Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com> --- fs/btrfs/ctree.h | 2 -- fs/btrfs/disk-io.c | 1 - fs/btrfs/inode.c | 7 +++---- fs/btrfs/zoned.c | 3 +-- 4 files changed, 4 insertions(+), 9 deletions(-)