[PATCH] blk: use find_first_zero_bit() in blk_queue_start_tag()

blk_queue_start_tag() hand-coded searching for the first zero bit in the tag
map.  Replace it with find_first_zero_bit().  With this patch,
blk_queue_star_tag() doesn't need to fill remains of tag map with 1, thus
allowing it to work properly with the next remove_real_max_depth patch.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Acked-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Tejun Heo 2005-06-23 00:08:48 -07:00 committed by Linus Torvalds
parent 15d20bfd60
commit 2bf0fdad51
1 changed files with 4 additions and 9 deletions

View File

@ -968,8 +968,7 @@ EXPORT_SYMBOL(blk_queue_end_tag);
int blk_queue_start_tag(request_queue_t *q, struct request *rq)
{
struct blk_queue_tag *bqt = q->queue_tags;
unsigned long *map = bqt->tag_map;
int tag = 0;
int tag;
if (unlikely((rq->flags & REQ_QUEUED))) {
printk(KERN_ERR
@ -978,14 +977,10 @@ int blk_queue_start_tag(request_queue_t *q, struct request *rq)
BUG();
}
for (map = bqt->tag_map; *map == -1UL; map++) {
tag += BLK_TAGS_PER_LONG;
tag = find_first_zero_bit(bqt->tag_map, bqt->max_depth);
if (tag >= bqt->max_depth)
return 1;
}
tag += ffz(*map);
__set_bit(tag, bqt->tag_map);
rq->flags |= REQ_QUEUED;