Move some lock_kernel() calls from the caller to the callee, reducing
holdtimes.
25-akpm/fs/jbd/transaction.c | 12 +++++++-----
1 files changed, 7 insertions(+), 5 deletions(-)
diff -puN fs/jbd/transaction.c~journal_get_write_access-speedup fs/jbd/transaction.c
--- 25/fs/jbd/transaction.c~journal_get_write_access-speedup Thu Jun 5 15:14:09 2003
+++ 25-akpm/fs/jbd/transaction.c Thu Jun 5 15:14:09 2003
@@ -688,7 +688,9 @@ done_locked:
/* If we are about to journal a buffer, then any revoke pending
on it is no longer valid. */
+ lock_kernel();
journal_cancel_revoke(handle, jh);
+ unlock_kernel();
out_unlocked:
if (frozen_buffer)
@@ -720,9 +722,7 @@ int journal_get_write_access (handle_t *
* log thread also manipulates. Make sure that the buffer
* completes any outstanding IO before proceeding. */
lock_journal(journal);
- lock_kernel();
rc = do_get_write_access(handle, jh, 0);
- unlock_kernel();
journal_unlock_journal_head(jh);
unlock_journal(journal);
return rc;
@@ -846,11 +846,14 @@ int journal_get_undo_access (handle_t *h
/* Do this first --- it can drop the journal lock, so we want to
* make sure that obtaining the committed_data is done
* atomically wrt. completion of any outstanding commits. */
- lock_kernel();
err = do_get_write_access (handle, jh, 1);
if (err)
goto out;
-
+
+ /*
+ * lock_journal() prevents jh->b_committed_data from getting set
+ * by two CPUs at the same time.
+ */
if (!jh->b_committed_data) {
/* Copy out the current buffer contents into the
* preserved, committed copy. */
@@ -870,7 +873,6 @@ int journal_get_undo_access (handle_t *h
}
out:
- unlock_kernel();
if (!err)
J_ASSERT_JH(jh, jh->b_committed_data);
journal_unlock_journal_head(jh);
_