jbd2: use kmem_cache_zalloc for allocating journal head

This commit tries to use kmem_cache_zalloc instead of kmem_cache_alloc/
memset when a new journal head is alloctated.

Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index 9545757..3cdd285 100644 (file)
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -2325,13 +2325,13 @@ static struct journal_head *journal_alloc_journal_head(void)
 #ifdef CONFIG_JBD2_DEBUG
        atomic_inc(&nr_journal_heads);
 #endif
-       ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS);
+       ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS);
        if (!ret) {
                jbd_debug(1, "out of memory for journal_head\n");
                pr_notice_ratelimited("ENOMEM in %s, retrying.\n", __func__);
                while (!ret) {
                        yield();
-                       ret = kmem_cache_alloc(jbd2_journal_head_cache, GFP_NOFS);
+                       ret = kmem_cache_zalloc(jbd2_journal_head_cache, GFP_NOFS);
                }
        }
        return ret;
@@ -2393,10 +2393,8 @@ struct journal_head *jbd2_journal_add_journal_head(struct buffer_head *bh)
        struct journal_head *new_jh = NULL;
 
 repeat:
-       if (!buffer_jbd(bh)) {
+       if (!buffer_jbd(bh))
                new_jh = journal_alloc_journal_head();
-               memset(new_jh, 0, sizeof(*new_jh));
-       }
 
        jbd_lock_bh_journal_head(bh);
        if (buffer_jbd(bh)) {