diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 4896d7a947eb..02895a126ab9 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1546,6 +1546,9 @@ struct btrfs_fs_info {
*/
struct btrfs_workqueue *fixup_workers;
struct btrfs_workqueue *delayed_workers;
+
+ /* the extent workers do delayed refs on the extent allocation tree */
+ struct btrfs_workqueue *extent_workers;
struct task_struct *transaction_kthread;
struct task_struct *cleaner_kthread;
int thread_pool_size;
@@ -3268,6 +3271,8 @@ int btrfs_check_space_for_delayed_refs(struct btrfs_trans_handle *trans,
void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
struct btrfs_root *root, unsigned long count);
+int btrfs_async_run_delayed_refs(struct btrfs_root *root,
+ unsigned long count, int wait);
int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len);
int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
struct btrfs_root *root, u64 bytenr,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 0c0fa78ef452..8bb4aa19898f 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2069,6 +2069,7 @@ static void btrfs_stop_all_workers(struct btrfs_fs_info *fs_info)
btrfs_destroy_workqueue(fs_info->readahead_workers);
btrfs_destroy_workqueue(fs_info->flush_workers);
btrfs_destroy_workqueue(fs_info->qgroup_rescan_workers);
+ btrfs_destroy_workqueue(fs_info->extent_workers);
}
static void free_root_extent_buffers(struct btrfs_root *root)
@@ -2586,6 +2587,10 @@ int open_ctree(struct super_block *sb,
btrfs_alloc_workqueue("readahead", flags, max_active, 2);
fs_info->qgroup_rescan_workers =
btrfs_alloc_workqueue("qgroup-rescan", flags, 1, 0);
+ fs_info->extent_workers =
+ btrfs_alloc_workqueue("extent-refs", flags,
+ min_t(u64, fs_devices->num_devices,
+ max_active), 8);
if (!(fs_info->workers && fs_info->delalloc_workers &&
fs_info->submit_workers && fs_info->flush_workers &&
@@ -2595,6 +2600,7 @@ int open_ctree(struct super_block *sb,
fs_info->endio_freespace_worker && fs_info->rmw_workers &&
fs_info->caching_workers && fs_info->readahead_workers &&
fs_info->fixup_workers && fs_info->delayed_workers &&
+ fs_info->fixup_workers && fs_info->extent_workers &&
fs_info->qgroup_rescan_workers)) {
err = -ENOMEM;
goto fail_sb_buffer;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index bb5b3067ddc3..6caddd5970e4 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2674,15 +2674,94 @@ int btrfs_should_throttle_delayed_refs(struct btrfs_trans_handle *trans,
u64 num_entries =
atomic_read(&trans->transaction->delayed_refs.num_entries);
u64 avg_runtime;
+ u64 val;
smp_mb();
avg_runtime = fs_info->avg_delayed_ref_runtime;
+ val = num_entries * avg_runtime;
if (num_entries * avg_runtime >= NSEC_PER_SEC)
return 1;
+ if (val >= NSEC_PER_SEC / 2)
+ return 2;
return btrfs_check_space_for_delayed_refs(trans, root);
}
+struct async_delayed_refs {
+ struct btrfs_root *root;
+ int count;
+ int error;
+ int sync;
+ struct completion wait;
+ struct btrfs_work work;
+};
+
+static void delayed_ref_async_start(struct btrfs_work *work)
+{
+ struct async_delayed_refs *async;
+ struct btrfs_trans_handle *trans;
+ int ret;
+
+ async = container_of(work, struct async_delayed_refs, work);
+
+ trans = btrfs_join_transaction(async->root);
+ if (IS_ERR(trans)) {
+ async->error = PTR_ERR(trans);
+ goto done;
+ }
+
+ /*
+ * trans->sync means that when we call end_transaciton, we won't
+ * wait on delayed refs
+ */
+ trans->sync = true;
+ ret = btrfs_run_delayed_refs(trans, async->root, async->count);
+ if (ret)
+ async->error = ret;
+
+ ret = btrfs_end_transaction(trans, async->root);
+ if (ret && !async->error)
+ async->error = ret;
+done:
+ if (async->sync)
+ complete(&async->wait);
+ else
+ kfree(async);
+}
+
+int btrfs_async_run_delayed_refs(struct btrfs_root *root,
+ unsigned long count, int wait)
+{
+ struct async_delayed_refs *async;
+ int ret;
+
+ async = kmalloc(sizeof(*async), GFP_NOFS);
+ if (!async)
+ return -ENOMEM;
+
+ async->root = root->fs_info->tree_root;
+ async->count = count;
+ async->error = 0;
+ if (wait)
+ async->sync = 1;
+ else
+ async->sync = 0;
+ init_completion(&async->wait);
+
+ btrfs_init_work(&async->work, delayed_ref_async_start,
+ NULL, NULL);
+
+ btrfs_queue_work(root->fs_info->extent_workers, &async->work);
+
+ if (wait) {
+ wait_for_completion(&async->wait);
+ ret = async->error;
+ kfree(async);
+ return ret;
+ }
+ return 0;
+}
+
/*
* this starts processing the delayed reference count updates and
* extent insertions we have queued up so far. count can be
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 992aae6c00b0..38d1e7b976d8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2678,6 +2678,7 @@ static int btrfs_finish_ordered_io(struct btrfs_ordered_extent *ordered_extent)
trans = NULL;
goto out_unlock;
}
+
trans->block_rsv = &root->fs_info->delalloc_block_rsv;
if (test_bit(BTRFS_ORDERED_COMPRESSED, &ordered_extent->flags))
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 3aafbde8b637..1c54e2eb74ab 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -697,6 +697,7 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
unsigned long cur = trans->delayed_ref_updates;
int lock = (trans->type != TRANS_JOIN_NOLOCK);
int err = 0;
+ int must_run_delayed_refs = 0;
if (trans->use_count > 1) {
trans->use_count--;
@@ -711,10 +712,18 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
btrfs_create_pending_block_groups(trans, root);
trans->delayed_ref_updates = 0;
- if (!trans->sync && btrfs_should_throttle_delayed_refs(trans, root)) {
+ if (!trans->sync) {
+ must_run_delayed_refs =
+ btrfs_should_throttle_delayed_refs(trans, root);
cur = max_t(unsigned long, cur, 32);
- trans->delayed_ref_updates = 0;
- btrfs_run_delayed_refs(trans, root, cur);
+
+ /*
+ * don't make the caller wait if they are from a NOLOCK
+ * or ATTACH transaction, it will deadlock with commit
+ */
+ if (must_run_delayed_refs == 1 &&
+ (trans->type & (__TRANS_JOIN_NOLOCK | __TRANS_ATTACH)))
+ must_run_delayed_refs = 2;
}
if (trans->qgroup_reserved) {
@@ -775,6 +784,10 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
assert_qgroups_uptodate(trans);
kmem_cache_free(btrfs_trans_handle_cachep, trans);
+ if (must_run_delayed_refs) {
+ btrfs_async_run_delayed_refs(root, cur,
+ must_run_delayed_refs == 1);
+ }
return err;
}