From 161c3549b45aeef05451b6822d8aaaf39c7bedce Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 24 Sep 2015 16:17:39 -0400 Subject: Btrfs: change how we wait for pending ordered extents We have a mechanism to make sure we don't lose updates for ordered extents that were logged in the transaction that is currently running. We add the ordered extent to a transaction list and then the transaction waits on all the ordered extents in that list. However are substantially large file systems this list can be extremely large, and can give us soft lockups, since the ordered extents don't remove themselves from the list when they do complete. To fix this we simply add a counter to the transaction that is incremented any time we have a logged extent that needs to be completed in the current transaction. Then when the ordered extent finally completes it decrements the per transaction counter and wakes up the transaction if we are the last ones. This will eliminate the softlockup. Thanks, Signed-off-by: Josef Bacik Signed-off-by: Chris Mason --- fs/btrfs/disk-io.c | 20 -------------------- 1 file changed, 20 deletions(-) (limited to 'fs/btrfs/disk-io.c') diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index bcbb596d9695..dceabb13ddc4 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -4326,25 +4326,6 @@ again: return 0; } -static void btrfs_free_pending_ordered(struct btrfs_transaction *cur_trans, - struct btrfs_fs_info *fs_info) -{ - struct btrfs_ordered_extent *ordered; - - spin_lock(&fs_info->trans_lock); - while (!list_empty(&cur_trans->pending_ordered)) { - ordered = list_first_entry(&cur_trans->pending_ordered, - struct btrfs_ordered_extent, - trans_list); - list_del_init(&ordered->trans_list); - spin_unlock(&fs_info->trans_lock); - - btrfs_put_ordered_extent(ordered); - spin_lock(&fs_info->trans_lock); - } - spin_unlock(&fs_info->trans_lock); -} - void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, struct btrfs_root *root) { @@ -4356,7 +4337,6 @@ void btrfs_cleanup_one_transaction(struct btrfs_transaction *cur_trans, cur_trans->state = TRANS_STATE_UNBLOCKED; wake_up(&root->fs_info->transaction_wait); - btrfs_free_pending_ordered(cur_trans, root->fs_info); btrfs_destroy_delayed_inodes(root); btrfs_assert_delayed_root_empty(root); -- cgit v1.2.3