fs, jbd: pull your plug when waiting for space

With an -rt kernel, and a heavy sync IO load, tasks can jam up on journal locks without unplugging, which can lead to terminal IO starvation. Unplug and schedule when waiting for space. Signed-off-by: Mike Galbraith <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Theodore Tso <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Thomas Gleixner <[email protected]>
jepler · Dec 18, 2013 · 27556a5 · 27556a5
1 parent e91f4ed
commit 27556a5
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/fs/jbd/checkpoint.c b/fs/jbd/checkpoint.c
@@ -129,6 +129,8 @@ void __log_wait_for_space(journal_t *journal)
 		if (journal->j_flags & JFS_ABORT)
 			return;
 		spin_unlock(&journal->j_state_lock);
+		if (current->plug)
+			io_schedule();
 		mutex_lock(&journal->j_checkpoint_mutex);
 
 		/*