Commit f36f3042 authored by Chris Mason's avatar Chris Mason
Browse files

Btrfs: be more polite in the async caching threads 



The semaphore used by the async caching threads can prevent a
transaction commit, which can make the FS appear to stall.  This
releases the semaphore more often when a transaction commit is
in progress.

Signed-off-by: default avatarChris Mason <chris.mason@oracle.com>
parent 276e680d

fs/btrfs/extent-tree.c

+3 −2
Original line number Diff line number Diff line
@@ -302,10 +302,11 @@ static int caching_kthread(void *data) 
			else if (ret)

				break;



			if (need_resched()) {

			if (need_resched() ||

			    btrfs_transaction_in_commit(fs_info)) {

				btrfs_release_path(fs_info->extent_root, path);

				up_read(&fs_info->extent_commit_sem);

				cond_resched();

				schedule_timeout(1);

				goto again;

			}

fs/btrfs/transaction.c

+10 −0
Original line number Diff line number Diff line
@@ -857,6 +857,16 @@ static void update_super_roots(struct btrfs_root *root) 
	super->root_level = root_item->level;

}



int btrfs_transaction_in_commit(struct btrfs_fs_info *info)

{

	int ret = 0;

	spin_lock(&info->new_trans_lock);

	if (info->running_transaction)

		ret = info->running_transaction->in_commit;

	spin_unlock(&info->new_trans_lock);

	return ret;

}



int btrfs_commit_transaction(struct btrfs_trans_handle *trans,

			     struct btrfs_root *root)

{

fs/btrfs/transaction.h

+1 −0
Original line number Diff line number Diff line
@@ -107,4 +107,5 @@ int btrfs_record_root_in_trans(struct btrfs_trans_handle *trans, 
				struct btrfs_root *root);

int btrfs_write_and_wait_marked_extents(struct btrfs_root *root,

					struct extent_io_tree *dirty_pages);

int btrfs_transaction_in_commit(struct btrfs_fs_info *info);

#endif