From: Jeff Moyer <jmoyer@redhat.com> Date: Tue, 3 Nov 2009 11:36:43 -0500 Subject: [block] cfq: change the meaning of the cfqq_coop flag Message-id: 1257266206-24003-10-git-send-email-jmoyer@redhat.com O-Subject: [PATCH 09/12] cfq: change the meaning of the cfqq_coop flag Bugzilla: 456181 448130 427709 RH-Acked-by: Josef Bacik <josef@redhat.com> RH-Acked-by: Rik van Riel <riel@redhat.com> RH-Acked-by: Vivek Goyal <vgoyal@redhat.com> commit b3b6d0408c953524f979468562e7e210d8634150 Author: Jeff Moyer <jmoyer@redhat.com> Date: Fri Oct 23 17:14:51 2009 -0400 cfq: change the meaning of the cfqq_coop flag The flag used to indicate that a cfqq was allowed to jump ahead in the scheduling order due to submitting a request close to the queue that just executed. Since closely cooperating queues are now merged, the flag holds little meaning. Change it to indicate that multiple queues were merged. This will later be used to allow the breaking up of merged queues when they are no longer cooperating. Signed-off-by: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Jens Axboe <jens.axboe@oracle.com> diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 9d38fd8..69c906f 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -1019,9 +1019,6 @@ static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd, mod_timer(&cfqd->idle_class_timer, end); } - if (cfqq) - cfq_clear_cfqq_coop(cfqq); - set_queue: __cfq_set_active_queue(cfqd, cfqq); return cfqq; @@ -1079,8 +1076,7 @@ static struct cfq_queue *cfqq_close(struct cfq_data *cfqd, * assumption. */ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd, - struct cfq_queue *cur_cfqq, - int probe) + struct cfq_queue *cur_cfqq) { struct cfq_queue *cfqq; @@ -1099,11 +1095,6 @@ static struct cfq_queue *cfq_close_cooperator(struct cfq_data *cfqd, if (!cfq_cfqq_sync(cfqq)) return NULL; - if (cfq_cfqq_coop(cfqq)) - return NULL; - - if (!probe) - cfq_mark_cfqq_coop(cfqq); return cfqq; } @@ -1287,7 +1278,7 @@ static struct cfq_queue *cfq_select_queue(struct cfq_data *cfqd) * cooperators and put the close queue at the front of the service * tree. If possible, merge the expiring queue with the new cfqq. */ - else if ((new_cfqq = cfq_close_cooperator(cfqd, cfqq, 0))) { + else if ((new_cfqq = cfq_close_cooperator(cfqd, cfqq))) { if (!cfqq->new_cfqq) cfq_setup_merge(cfqq, new_cfqq); goto expire; @@ -2152,7 +2143,7 @@ static void cfq_completed_request(request_queue_t *q, struct request *rq) if (time_after(now, cfqq->slice_end)) cfq_slice_expired(cfqd, 0); else if (cfqq_empty && - !cfq_close_cooperator(cfqd, cfqq, 1) && sync) + !cfq_close_cooperator(cfqd, cfqq) && sync) cfq_arm_slice_timer(cfqd, cfqq); } @@ -2301,6 +2292,7 @@ cfq_merge_cfqqs(struct cfq_data *cfqd, struct cfq_io_context *cic, struct cfq_queue *cfqq) { cic->cfqq[SYNC] = cfqq->new_cfqq; + cfq_mark_cfqq_coop(cfqq->new_cfqq); cfq_put_queue(cfqq); return cic->cfqq[SYNC]; }