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/

