From d7b7630130e52361af66ce3b994696e2357ba7de Mon Sep 17 00:00:00 2001 From: Richard Kennedy Date: Wed, 13 Jul 2011 21:17:23 +0200 Subject: [PATCH] block: reorder request_queue to remove 64 bit alignment padding Reorder request_queue to remove 16 bytes of alignment padding in 64 bit builds. On my config this shrinks the size of this structure from 1608 to 1592 bytes and therefore needs one fewer cachelines. Also trivially move the open bracket { to be on the same line as the structure name to make it easier to grep. Signed-off-by: Richard Kennedy Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 6dcea68..c0cd9a2 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -260,8 +260,7 @@ struct queue_limits { unsigned char discard_zeroes_data; }; -struct request_queue -{ +struct request_queue { /* * Together with queue_head for cacheline sharing */ @@ -304,14 +303,14 @@ struct request_queue void *queuedata; /* - * queue needs bounce pages for pages above this limit + * various queue flags, see QUEUE_* below */ - gfp_t bounce_gfp; + unsigned long queue_flags; /* - * various queue flags, see QUEUE_* below + * queue needs bounce pages for pages above this limit */ - unsigned long queue_flags; + gfp_t bounce_gfp; /* * protects queue structures from reentrancy. ->__queue_lock should @@ -334,8 +333,8 @@ struct request_queue unsigned int nr_congestion_off; unsigned int nr_batching; - void *dma_drain_buffer; unsigned int dma_drain_size; + void *dma_drain_buffer; unsigned int dma_pad_mask; unsigned int dma_alignment; -- 2.7.4