ext4: pack ioend structure better
authorJan Kara <jack@suse.cz>
Wed, 9 Mar 2016 03:26:39 +0000 (22:26 -0500)
committerTheodore Ts'o <tytso@mit.edu>
Wed, 9 Mar 2016 03:26:39 +0000 (22:26 -0500)
On 64-bit architectures we have two 4-byte holes in struct ext4_io_end.
Order entries better to avoid this and thus make the structure occupy
64 instead of 72 bytes for 64-bit architectures.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
fs/ext4/ext4.h

index 157b458a69d4b7c334f28b80c37fd5d11c9f0c25..5035dfebdbaf4c499bdb3f9ce7c600d5d9bfee11 100644 (file)
@@ -182,9 +182,9 @@ typedef struct ext4_io_end {
        struct bio              *bio;           /* Linked list of completed
                                                 * bios covering the extent */
        unsigned int            flag;           /* unwritten or not */
+       atomic_t                count;          /* reference counter */
        loff_t                  offset;         /* offset in the file */
        ssize_t                 size;           /* size of the extent */
-       atomic_t                count;          /* reference counter */
 } ext4_io_end_t;
 
 struct ext4_io_submit {