Commits
Jan Schmidt committed 8ca78f3eda4
Btrfs: avoid waiting for delayed refs when we must not We track two conditions to decide if we should sleep while waiting for more delayed refs, the number of delayed refs (num_refs) and the first entry in the list of blockers (first_seq). When we suspect staleness, we save num_refs and do one more cycle. If nothing changes, we then save first_seq for later comparison and do wait_event. We ought to save first_seq the very same moment we're saving num_refs. Otherwise we cannot be sure that nothing has changed and we might start waiting when we shouldn't, which could lead to starvation. Signed-off-by: Jan Schmidt <list.btrfs@jan-o-sch.net>