ocfs2: limit printk when journal is aborted

Once JBD2_ABORT is set, ocfs2_commit_cache will fail in
ocfs2_commit_thread.  Then it will get into a loop with mass logs.  This
will meaninglessly consume a larger number of resource and may lead to
the system hanging.  So limit printk in this case.

[akpm@linux-foundation.org: document the msleep]
Signed-off-by: Joseph Qi <joseph.qi@huawei.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/fs/ocfs2/journal.c b/fs/ocfs2/journal.c
index 03ea9314fecd7c1f7de6ba659a659b0ebda57c75..4b0c68849b3610ec1e448607b376c6545a1738ed 100644 (file)
--- a/fs/ocfs2/journal.c
+++ b/fs/ocfs2/journal.c
@@ -30,6 +30,7 @@
 #include <linux/kthread.h>
 #include <linux/time.h>
 #include <linux/random.h>
+#include <linux/delay.h>
 
 #include <cluster/masklog.h>
 
@@ -2185,8 +2186,20 @@ static int ocfs2_commit_thread(void *arg)
                                         || kthread_should_stop());
 
                status = ocfs2_commit_cache(osb);
-               if (status < 0)
-                       mlog_errno(status);
+               if (status < 0) {
+                       static unsigned long abort_warn_time;
+
+                       /* Warn about this once per minute */
+                       if (printk_timed_ratelimit(&abort_warn_time, 60*HZ))
+                               mlog(ML_ERROR, "status = %d, journal is "
+                                               "already aborted.\n", status);
+                       /*
+                        * After ocfs2_commit_cache() fails, j_num_trans has a
+                        * non-zero value.  Sleep here to avoid a busy-wait
+                        * loop.
+                        */
+                       msleep_interruptible(1000);
+               }
 
                if (kthread_should_stop() && atomic_read(&journal->j_num_trans)){
                        mlog(ML_KTHREAD,