ext4: disable synchronous transaction batching if max_batch_time==0
The mount manpage says of the max_batch_time option,
This optimization can be turned off entirely
by setting max_batch_time to 0.
But the code doesn't do that. So fix the code to do
that.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@vger.kernel.org
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 3423947..6297c07 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1525,8 +1525,6 @@
arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
sbi->s_commit_interval = HZ * arg;
} else if (token == Opt_max_batch_time) {
- if (arg == 0)
- arg = EXT4_DEF_MAX_BATCH_TIME;
sbi->s_max_batch_time = arg;
} else if (token == Opt_min_batch_time) {
sbi->s_min_batch_time = arg;
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 38cfcf5..6f0f590 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1588,9 +1588,12 @@
* to perform a synchronous write. We do this to detect the
* case where a single process is doing a stream of sync
* writes. No point in waiting for joiners in that case.
+ *
+ * Setting max_batch_time to 0 disables this completely.
*/
pid = current->pid;
- if (handle->h_sync && journal->j_last_sync_writer != pid) {
+ if (handle->h_sync && journal->j_last_sync_writer != pid &&
+ journal->j_max_batch_time) {
u64 commit_time, trans_time;
journal->j_last_sync_writer = pid;