block: unalign call_single_data in struct request

commit 4ccafe032005e9b96acbef2e389a4de5b1254add upstream.

A previous change blindly added massive alignment to the
call_single_data structure in struct request. This ballooned it in size
from 296 to 320 bytes on my setup, for no valid reason at all.

Use the unaligned struct __call_single_data variant instead.

Fixes: 966a967116e69 ("smp: Avoid using two cache lines for struct call_single_data")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8da66379f7ea7afceb9af2f32f998d7ca71c25a7..fd47bd96b5d3d8fb125db979a16a3f7092b005c7 100644 (file)
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -135,7 +135,7 @@ typedef __u32 __bitwise req_flags_t;
 struct request {
        struct list_head queuelist;
        union {
-               call_single_data_t csd;
+               struct __call_single_data csd;
                u64 fifo_time;
        };