From: Theodore Ts'o <tytso@mit.edu>
Date: Sun, 9 Mar 2014 05:07:19 +0000 (-0500)
Subject: jbd2: check jh->b_transaction without taking j_list_lock
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d2eb0b998990abf51d6e1d3bf16a2637b920a660;p=linux-beck.git

jbd2: check jh->b_transaction without taking j_list_lock

jh->b_transaction is adequately protected for reading by the
jbd_lock_bh_state(bh), so we don't need to take j_list_lock in
__journal_try_to_free_buffer().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
index 60bb365f54a5..78900a1252b2 100644
--- a/fs/jbd2/transaction.c
+++ b/fs/jbd2/transaction.c
@@ -1821,11 +1821,11 @@ __journal_try_to_free_buffer(journal_t *journal, struct buffer_head *bh)
 	if (buffer_locked(bh) || buffer_dirty(bh))
 		goto out;
 
-	if (jh->b_next_transaction != NULL)
+	if (jh->b_next_transaction != NULL || jh->b_transaction != NULL)
 		goto out;
 
 	spin_lock(&journal->j_list_lock);
-	if (jh->b_cp_transaction != NULL && jh->b_transaction == NULL) {
+	if (jh->b_cp_transaction != NULL) {
 		/* written-back checkpointed metadata buffer */
 		JBUFFER_TRACE(jh, "remove from checkpoint list");
 		__jbd2_journal_remove_checkpoint(jh);