jbd2: Use round-jiffies() function for the "5 second" ext4/jbd2 wakeup

While "every 5 seconds" doesn't sound as a problem, there can be many
of these (and these timers do add up over all the kernel).  The "5
second" wakeup isn't really timing sensitive; in addition even with
rounding it'll still happen every 5 seconds (with the exception of the
very first time, which is likely to be rounded up to somewhere closer
to 6 seconds)

(Ported from similar JBD patch made by Arjan van de Ven to
fs/jbd/transaction.c)

Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 70b3199e69dc02050a33b9630e0deb07f09fe1e2..0c8adaba0c0b5d83c353b81b7851226bd5dd9236 100644 (file)
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -54,7 +54,7 @@ jbd2_get_transaction(journal_t *journal, transaction_t *transaction)
        spin_lock_init(&transaction->t_handle_lock);
 
        /* Set up the commit timer for the new transaction. */
-       journal->j_commit_timer.expires = transaction->t_expires;
+       journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);
        add_timer(&journal->j_commit_timer);
 
        J_ASSERT(journal->j_running_transaction == NULL);