diff options
author | Mike Snitzer <snitzer@redhat.com> | 2011-02-11 10:08:00 (GMT) |
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committer | Jens Axboe <jaxboe@fusionio.com> | 2011-02-11 10:08:00 (GMT) |
commit | c186794dbb466b45cf40f942f2d09d6d5b4b0e42 (patch) | |
tree | 07ccd819bb6cced2c19053d2ed97ebaac88f824e /include/linux | |
parent | 9d5a4e946ce5352f19400b6370f4cd8e72806278 (diff) | |
download | linux-fsl-qoriq-c186794dbb466b45cf40f942f2d09d6d5b4b0e42.tar.xz |
block: share request flush fields with elevator_private
Flush requests are never put on the IO scheduler. Convert request
structure's elevator_private* into an array and have the flush fields
share a union with it.
Reclaim the space lost in 'struct request' by moving 'completion_data'
back in the union with 'rb_node'.
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'include/linux')
-rw-r--r-- | include/linux/blkdev.h | 23 |
1 files changed, 12 insertions, 11 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 6d7e9af..12bb426 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -99,25 +99,26 @@ struct request { /* * The rb_node is only used inside the io scheduler, requests * are pruned when moved to the dispatch queue. So let the - * flush fields share space with the rb_node. + * completion_data share space with the rb_node. */ union { struct rb_node rb_node; /* sort/lookup */ - struct { - unsigned int seq; - struct list_head list; - } flush; + void *completion_data; }; - void *completion_data; - /* * Three pointers are available for the IO schedulers, if they need - * more they have to dynamically allocate it. + * more they have to dynamically allocate it. Flush requests are + * never put on the IO scheduler. So let the flush fields share + * space with the three elevator_private pointers. */ - void *elevator_private; - void *elevator_private2; - void *elevator_private3; + union { + void *elevator_private[3]; + struct { + unsigned int seq; + struct list_head list; + } flush; + }; struct gendisk *rq_disk; unsigned long start_time; |