jbd2_user_of_the_jiffes_rounding_code.patch

   1 jbd2: Use round-jiffies() function for the "5 second" ext4/jbd2 wakeup
   2
   3 From: Mingming Cao <cmm@us.ibm.com>
   4
   5 While "every 5 seconds" doesn't sound as a problem, there can be many
   6 of these (and these timers do add up over all the kernel).  The "5
   7 second" wakeup isn't really timing sensitive; in addition even with
   8 rounding it'll still happen every 5 seconds (with the exception of the
   9 very first time, which is likely to be rounded up to somewhere closer
  10 to 6 seconds)
  11
  12 (Ported from similar JBD patch made by Arjan van de Ven to
  13 fs/jbd/transaction.c)
  14
  15 Cc: Arjan van de Ven <arjan@linux.intel.com>
  16 Cc: Andrew Morton <akpm@osdl.org>
  17 Signed-off-by: Mingming Cao <cmm@us.ibm.com>
  18 Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
  19
  20 ---
  21  fs/jbd2/transaction.c |    2 +-
  22  1 file changed, 1 insertion(+), 1 deletion(-)
  23
  24 Index: linux-2.6.24-rc7/fs/jbd2/transaction.c
  25 ===================================================================
  26 --- linux-2.6.24-rc7.orig/fs/jbd2/transaction.c 2008-01-16 15:41:14.000000000 -0800
  27 +++ linux-2.6.24-rc7/fs/jbd2/transaction.c      2008-01-16 17:49:48.000000000 -0800
  28 @@ -54,7 +54,7 @@ jbd2_get_transaction(journal_t *journal,
  29         spin_lock_init(&transaction->t_handle_lock);
  30
  31         /* Set up the commit timer for the new transaction. */
  32 -       journal->j_commit_timer.expires = transaction->t_expires;
  33 +       journal->j_commit_timer.expires = round_jiffies(transaction->t_expires);
  34         add_timer(&journal->j_commit_timer);
  35
  36         J_ASSERT(journal->j_running_transaction == NULL);