ext2: optimize ext2_xattr_get()

Since xattr entry names are sorted, we don't have
to continue when current entry name is greater than
target.

Signed-off-by: Chengguang Xu <cgxu519@zoho.com.cn>
Signed-off-by: Jan Kara <jack@suse.cz>

diff --git a/fs/ext2/xattr.c b/fs/ext2/xattr.c
index 59356cd..839e71e 100644 (file)
--- a/fs/ext2/xattr.c
+++ b/fs/ext2/xattr.c
@@ -199,7 +199,7 @@ ext2_xattr_get(struct inode *inode, int name_index, const char *name,
        struct ext2_xattr_entry *entry;
        size_t name_len, size;
        char *end;
-       int error;
+       int error, not_found;
        struct mb_cache *ea_block_cache = EA_BLOCK_CACHE(inode);
 
        ea_idebug(inode, "name=%d.%s, buffer=%p, buffer_size=%ld",
@@ -238,10 +238,14 @@ bad_block:
                if (!ext2_xattr_entry_valid(entry, end,
                    inode->i_sb->s_blocksize))
                        goto bad_block;
-               if (name_index == entry->e_name_index &&
-                   name_len == entry->e_name_len &&
-                   memcmp(name, entry->e_name, name_len) == 0)
+
+               not_found = ext2_xattr_cmp_entry(name_index, name_len, name,
+                                                entry);
+               if (!not_found)
                        goto found;
+               if (not_found < 0)
+                       break;
+
                entry = EXT2_XATTR_NEXT(entry);
        }
        if (ext2_xattr_cache_insert(ea_block_cache, bh))