From: Niu Yawei <[email protected]>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit f1167009711032b0d747ec89a632a626c901a1ad upstream.

In ext4_mb_add_n_trim(), lg_prealloc_lock should be taken when
changing the lg_prealloc_list.

Signed-off-by: Niu Yawei <[email protected]>
Signed-off-by: "Theodore Ts'o" <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
 fs/ext4/mballoc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index f1c9a84c50a3..5e440caf82de 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -4153,7 +4153,7 @@ static void ext4_mb_add_n_trim(struct 
ext4_allocation_context *ac)
                /* The max size of hash table is PREALLOC_TB_SIZE */
                order = PREALLOC_TB_SIZE - 1;
        /* Add the prealloc space to lg */
-       rcu_read_lock();
+       spin_lock(&lg->lg_prealloc_lock);
        list_for_each_entry_rcu(tmp_pa, &lg->lg_prealloc_list[order],
                                                pa_inode_list) {
                spin_lock(&tmp_pa->pa_lock);
@@ -4177,12 +4177,12 @@ static void ext4_mb_add_n_trim(struct 
ext4_allocation_context *ac)
        if (!added)
                list_add_tail_rcu(&pa->pa_inode_list,
                                        &lg->lg_prealloc_list[order]);
-       rcu_read_unlock();
+       spin_unlock(&lg->lg_prealloc_lock);
 
        /* Now trim the list to be not more than 8 elements */
        if (lg_prealloc_count > 8) {
                ext4_mb_discard_lg_preallocations(sb, lg,
-                                               order, lg_prealloc_count);
+                                                 order, lg_prealloc_count);
                return;
        }
        return ;
-- 
1.8.5.2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to