From c244bb50a9baa2ec47a458bbafb36b5e559ed5fa Mon Sep 17 00:00:00 2001 From: Vivek Goyal Date: Tue, 8 Dec 2009 17:52:57 -0500 Subject: [PATCH] cfq-iosched: Get rid of cfqq wait_busy_done flag o Get rid of wait_busy_done flag. This flag only tells we were doing wait busy on a queue and that queue got request so expire it. That information can easily be obtained by (cfq_cfqq_wait_busy() && queue_is_not_empty). So remove this flag and keep code simple. Signed-off-by: Vivek Goyal Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 17 ++++++++--------- 1 file changed, 8 insertions(+), 9 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index b19cd684bf1..f41fdb5f3e0 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -319,7 +319,6 @@ enum cfqq_state_flags { CFQ_CFQQ_FLAG_coop, /* cfqq is shared */ CFQ_CFQQ_FLAG_deep, /* sync cfqq experienced large depth */ CFQ_CFQQ_FLAG_wait_busy, /* Waiting for next request */ - CFQ_CFQQ_FLAG_wait_busy_done, /* Got new request. Expire the queue */ }; #define CFQ_CFQQ_FNS(name) \ @@ -348,7 +347,6 @@ CFQ_CFQQ_FNS(sync); CFQ_CFQQ_FNS(coop); CFQ_CFQQ_FNS(deep); CFQ_CFQQ_FNS(wait_busy); -CFQ_CFQQ_FNS(wait_busy_done); #undef CFQ_CFQQ_FNS #ifdef CONFIG_DEBUG_CFQ_IOSCHED @@ -1574,7 +1572,6 @@ __cfq_slice_expired(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfq_clear_cfqq_wait_request(cfqq); cfq_clear_cfqq_wait_busy(cfqq); - cfq_clear_cfqq_wait_busy_done(cfqq); /* * store what was left of this slice, if the queue idled/timed out @@ -2134,11 +2131,17 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) if (!cfqd->rq_queued) return NULL; + + /* + * We were waiting for group to get backlogged. Expire the queue + */ + if (cfq_cfqq_wait_busy(cfqq) && !RB_EMPTY_ROOT(&cfqq->sort_list)) + goto expire; + /* * The active queue has run out of time, expire it and select new. */ - if ((cfq_slice_used(cfqq) || cfq_cfqq_wait_busy_done(cfqq)) - && !cfq_cfqq_must_dispatch(cfqq)) + if (cfq_slice_used(cfqq) && !cfq_cfqq_must_dispatch(cfqq)) goto expire; /* @@ -3171,10 +3174,6 @@ cfq_rq_enqueued(struct cfq_data *cfqd, struct cfq_queue *cfqq, cfqq->last_request_pos = blk_rq_pos(rq) + blk_rq_sectors(rq); if (cfqq == cfqd->active_queue) { - if (cfq_cfqq_wait_busy(cfqq)) { - cfq_clear_cfqq_wait_busy(cfqq); - cfq_mark_cfqq_wait_busy_done(cfqq); - } /* * Remember that we saw a request from this process, but * don't start queuing just yet. Otherwise we risk seeing lots