diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index a9377fb16c37..293464c0c6ba 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -522,6 +522,7 @@ struct btrfs_fs_info { struct work_struct async_submit_work; spinlock_t end_io_work_lock; spinlock_t async_submit_work_lock; + atomic_t nr_async_submits; #if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,18) struct work_struct trans_work; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 264f297260f8..373374340e9b 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -453,6 +453,7 @@ int btrfs_wq_submit_bio(struct btrfs_fs_info *fs_info, struct inode *inode, spin_lock(&fs_info->async_submit_work_lock); list_add_tail(&async->list, &fs_info->async_submit_work_list); + atomic_inc(&fs_info->nr_async_submits); spin_unlock(&fs_info->async_submit_work_lock); queue_work(async_submit_workqueue, &fs_info->async_submit_work); @@ -906,10 +907,16 @@ static int btrfs_congested_fn(void *congested_data, int bdi_bits) { struct btrfs_fs_info *info = (struct btrfs_fs_info *)congested_data; int ret = 0; + int limit = 256 * info->fs_devices->open_devices; struct list_head *cur; struct btrfs_device *device; struct backing_dev_info *bdi; + if ((bdi_bits & (1 << BDI_write_congested)) && + atomic_read(&info->nr_async_submits) > limit) { + return 1; + } + list_for_each(cur, &info->fs_devices->devices) { device = list_entry(cur, struct btrfs_device, dev_list); if (!device->bdev) @@ -1117,6 +1124,7 @@ static void btrfs_async_submit_work(struct work_struct *work) } next = fs_info->async_submit_work_list.next; list_del(next); + atomic_dec(&fs_info->nr_async_submits); spin_unlock(&fs_info->async_submit_work_lock); async = list_entry(next, struct async_submit_bio, list); @@ -1179,6 +1187,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, INIT_LIST_HEAD(&fs_info->dirty_cowonly_roots); INIT_LIST_HEAD(&fs_info->space_info); btrfs_mapping_init(&fs_info->mapping_tree); + atomic_set(&fs_info->nr_async_submits, 0); fs_info->sb = sb; fs_info->max_extent = (u64)-1; fs_info->max_inline = 8192 * 1024;