lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

block: make queue flags non-atomic

Browse Source 
We can save some atomic ops in the IO path, if we clearly define
the rules of how to modify the queue flags.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Nick Piggin
2008-04-29 14:48:33 +02:00
committed by Jens Axboe
parent 68154e90c9
commit 75ad23bc0f
13 changed files with 101 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/md/dm-table.c
View File

@ -873,10 +873,13 @@ void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q)
q->max_hw_sectors = t->limits.max_hw_sectors;
q->seg_boundary_mask = t->limits.seg_boundary_mask;
q->bounce_pfn = t->limits.bounce_pfn;
/* XXX: the below will probably go bug. must ensure there can be no
* concurrency on queue_flags, and use the unlocked versions...
*/
if (t->limits.no_cluster)
q->queue_flags &= ~(1 << QUEUE_FLAG_CLUSTER);
queue_flag_clear(QUEUE_FLAG_CLUSTER, q);
else
q->queue_flags |= (1 << QUEUE_FLAG_CLUSTER);
queue_flag_set(QUEUE_FLAG_CLUSTER, q);
}