redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

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 <richard@rsk.demon.co.uk>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
hifive-unleashed-5.1
Richard Kennedy 2011-07-13 21:17:23 +02:00 committed by Jens Axboe
parent 7700fc4f67
commit d7b7630130
1 changed files with 7 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
include/linux/blkdev.h
View File

@ -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
*/
@ -303,16 +302,16 @@ struct request_queue
*/
void *queuedata;
/*
* queue needs bounce pages for pages above this limit
*/
gfp_t bounce_gfp;
/*
* various queue flags, see QUEUE_* below
*/
unsigned long queue_flags;
/*
* queue needs bounce pages for pages above this limit
*/
gfp_t bounce_gfp;
/*
* protects queue structures from reentrancy. ->__queue_lock should
* _never_ be used directly, it is queue private. always use
@ -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;