34 lines
1.2 KiB
Diff
34 lines
1.2 KiB
Diff
From c28e07715162bb1e1567a935b45772ca85a5267c Mon Sep 17 00:00:00 2001
|
|
From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
Date: Mon, 17 Feb 2014 17:30:03 +0100
|
|
Subject: [PATCH] fs: jbd2: pull your plug when waiting for space
|
|
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/3.14/patches-3.14.0-rt1.tar.xz
|
|
|
|
Two cps in parallel managed to stall the the ext4 fs. It seems that
|
|
journal code is either waiting for locks or sleeping waiting for
|
|
something to happen. This seems similar to what Mike observed on ext3,
|
|
here is his description:
|
|
|
|
|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.
|
|
|
|
Cc: stable-rt@vger.kernel.org
|
|
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
|
|
---
|
|
fs/jbd2/checkpoint.c | 2 ++
|
|
1 file changed, 2 insertions(+)
|
|
|
|
--- a/fs/jbd2/checkpoint.c
|
|
+++ b/fs/jbd2/checkpoint.c
|
|
@@ -125,6 +125,8 @@ void __jbd2_log_wait_for_space(journal_t
|
|
if (journal->j_flags & JBD2_ABORT)
|
|
return;
|
|
write_unlock(&journal->j_state_lock);
|
|
+ if (current->plug)
|
|
+ io_schedule();
|
|
mutex_lock(&journal->j_checkpoint_mutex);
|
|
|
|
/*
|