btrfs: get rid of endio_repair_workers

This was originally added in commit 8b110e393c5a ("Btrfs: implement
repair function when direct read fails") to avoid a deadlock. In that
commit, the direct I/O read endio executes on the endio_workers
workqueue, submits a repair bio, and waits for it to complete. The
repair bio endio must execute on a different workqueue, otherwise it
could block on the endio_workers workqueue becoming available, which
won't happen because the original endio is blocked on the repair bio.

As of the previous commit, the original endio doesn't wait for the
repair bio, so this separate workqueue is unnecessary.

Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index e4b8f5f..03ea737 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -758,7 +758,6 @@ struct btrfs_fs_info {
        struct btrfs_workqueue *endio_workers;
        struct btrfs_workqueue *endio_meta_workers;
        struct btrfs_workqueue *endio_raid56_workers;
-       struct btrfs_workqueue *endio_repair_workers;
        struct btrfs_workqueue *rmw_workers;
        struct btrfs_workqueue *endio_meta_write_workers;
        struct btrfs_workqueue *endio_write_workers;

diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index d10c7be..8ad4516 100644 (file)
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -709,9 +709,7 @@ static void end_workqueue_bio(struct bio *bio)
                else
                        wq = fs_info->endio_write_workers;
        } else {
-               if (unlikely(end_io_wq->metadata == BTRFS_WQ_ENDIO_DIO_REPAIR))
-                       wq = fs_info->endio_repair_workers;
-               else if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
+               if (end_io_wq->metadata == BTRFS_WQ_ENDIO_RAID56)
                        wq = fs_info->endio_raid56_workers;
                else if (end_io_wq->metadata)
                        wq = fs_info->endio_meta_workers;
@@ -1942,7 +1940,6 @@ static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
        btrfs_destroy_workqueue(fs_info->workers);
        btrfs_destroy_workqueue(fs_info->endio_workers);
        btrfs_destroy_workqueue(fs_info->endio_raid56_workers);
-       btrfs_destroy_workqueue(fs_info->endio_repair_workers);
        btrfs_destroy_workqueue(fs_info->rmw_workers);
        btrfs_destroy_workqueue(fs_info->endio_write_workers);
        btrfs_destroy_workqueue(fs_info->endio_freespace_worker);
@@ -2145,8 +2142,6 @@ static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
        fs_info->endio_raid56_workers =
                btrfs_alloc_workqueue(fs_info, "endio-raid56", flags,
                                      max_active, 4);
-       fs_info->endio_repair_workers =
-               btrfs_alloc_workqueue(fs_info, "endio-repair", flags, 1, 0);
        fs_info->rmw_workers =
                btrfs_alloc_workqueue(fs_info, "rmw", flags, max_active, 2);
        fs_info->endio_write_workers =
@@ -2170,7 +2165,6 @@ static int btrfs_init_workqueues(struct btrfs_fs_info *fs_info,
              fs_info->flush_workers &&
              fs_info->endio_workers && fs_info->endio_meta_workers &&
              fs_info->endio_meta_write_workers &&
-             fs_info->endio_repair_workers &&
              fs_info->endio_write_workers && fs_info->endio_raid56_workers &&
              fs_info->endio_freespace_worker && fs_info->rmw_workers &&
              fs_info->caching_workers && fs_info->readahead_workers &&

diff --git a/fs/btrfs/disk-io.h b/fs/btrfs/disk-io.h
index cd62911..734bc52 100644 (file)
--- a/fs/btrfs/disk-io.h
+++ b/fs/btrfs/disk-io.h
@@ -25,7 +25,6 @@ enum btrfs_wq_endio_type {
        BTRFS_WQ_ENDIO_METADATA,
        BTRFS_WQ_ENDIO_FREE_SPACE,
        BTRFS_WQ_ENDIO_RAID56,
-       BTRFS_WQ_ENDIO_DIO_REPAIR,
 };
 
 static inline u64 btrfs_sb_offset(int mirror)

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 1462f64..bd7453f 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -7388,7 +7388,7 @@ static inline blk_status_t submit_dio_repair_bio(struct inode *inode,
 
        BUG_ON(bio_op(bio) == REQ_OP_WRITE);
 
-       ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DIO_REPAIR);
+       ret = btrfs_bio_wq_end_io(fs_info, bio, BTRFS_WQ_ENDIO_DATA);
        if (ret)
                return ret;