[PATCH -next v5 1/3] block, bfq: record how many queues are busy in bfq_group

Yu Kuai
2022-04-28T11:54:34Z

Prepare to refactor the counting of 'num_groups_with_pending_reqs'.

Add a counter 'busy_queues' in bfq_group, and update it in
bfq_add/del_bfqq_busy().

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
---
block/bfq-cgroup.c | 1 +
block/bfq-iosched.h | 2 ++
block/bfq-wf2q.c | 20 ++++++++++++++++++++
3 files changed, 23 insertions(+)

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 09574af83566..4d516879d9fa 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -557,6 +557,7 @@ static void bfq_pd_init(struct blkg_policy_data *pd)
*/
bfqg->bfqd = bfqd;
bfqg->active_entities = 0;
+ bfqg->busy_queues = 0;
bfqg->online = true;
bfqg->rq_pos_tree = RB_ROOT;
}
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index 978ef5d6fe6a..3847f4ab77ac 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -906,6 +906,7 @@ struct bfq_group_data {
* are groups with more than one active @bfq_entity
* (see the comments to the function
* bfq_bfqq_may_idle()).
+ * @busy_queues: number of busy bfqqs.
* @rq_pos_tree: rbtree sorted by next_request position, used when
* determining if two or more queues have interleaving
* requests (see bfq_find_close_cooperator()).
@@ -942,6 +943,7 @@ struct bfq_group {
struct bfq_entity *my_entity;

int active_entities;
+ int busy_queues;

struct rb_root rq_pos_tree;

diff --git a/block/bfq-wf2q.c b/block/bfq-wf2q.c
index f8eb340381cf..d9ff33e0be38 100644
--- a/block/bfq-wf2q.c
+++ b/block/bfq-wf2q.c
@@ -218,6 +218,16 @@ static bool bfq_no_longer_next_in_service(struct bfq_entity *entity)
return false;
}

+static void bfq_inc_busy_queues(struct bfq_queue *bfqq)
+{
+ bfqq_group(bfqq)->busy_queues++;
+}
+
+static void bfq_dec_busy_queues(struct bfq_queue *bfqq)
+{
+ bfqq_group(bfqq)->busy_queues--;
+}
+
#else /* CONFIG_BFQ_GROUP_IOSCHED */

static bool bfq_update_parent_budget(struct bfq_entity *next_in_service)
@@ -230,6 +240,14 @@ static bool bfq_no_longer_next_in_service(struct bfq_entity *entity)
return true;
}

+static void bfq_inc_busy_queues(struct bfq_queue *bfqq)
+{
+}
+
+static void bfq_dec_busy_queues(struct bfq_queue *bfqq)
+{
+}
+
#endif /* CONFIG_BFQ_GROUP_IOSCHED */

/*
@@ -1660,6 +1678,7 @@ void bfq_del_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq,
bfq_clear_bfqq_busy(bfqq);

bfqd->busy_queues[bfqq->ioprio_class - 1]--;
+ bfq_inc_busy_queues(bfqq);

if (bfqq->wr_coeff > 1)
bfqd->wr_busy_queues--;
@@ -1683,6 +1702,7 @@ void bfq_add_bfqq_busy(struct bfq_data *bfqd, struct bfq_queue *bfqq)

bfq_mark_bfqq_busy(bfqq);
bfqd->busy_queues[bfqq->ioprio_class - 1]++;
+ bfq_dec_busy_queues(bfqq);

if (!bfqq->dispatched)
if (bfqq->wr_coeff == 1)
--
2.31.1