From f37bf75ca73d523ebaa7ceb44c45d8ecd05374fe Mon Sep 17 00:00:00 2001
From: Yu Kuai <yukuai3@huawei.com>
Date: Thu, 2 Feb 2023 21:49:13 +0800
Subject: [PATCH] block, bfq: cleanup 'bfqg->online'
After commit dfd6200a0954 ("blk-cgroup: support to track if policy is
online"), there is no need to do this again in bfq.
However, 'pd->online' is not protected by 'bfqd->lock', in order to make
sure bfq won't see that 'pd->online' is still set after bfq_pd_offline(),
clear it before bfq_pd_offline() is called. This is fine because other
polices doesn't use 'pd->online' and bfq_pd_offline() will move active
bfqq to root cgroup anyway.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20230202134913.2364549-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
block/bfq-cgroup.c | 4 +---
block/bfq-iosched.h | 2 --
block/blk-cgroup.c | 2 +-
3 files changed, 2 insertions(+), 6 deletions(-)
diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 4fdbbec71647..624530643a05 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -551,7 +551,6 @@ static void bfq_pd_init(struct blkg_policy_data *pd)
bfqg->bfqd = bfqd;
bfqg->active_entities = 0;
bfqg->num_queues_with_pending_reqs = 0;
- bfqg->online = true;
bfqg->rq_pos_tree = RB_ROOT;
}
@@ -614,7 +613,7 @@ struct bfq_group *bfq_bio_bfqg(struct bfq_data *bfqd, struct bio *bio)
continue;
}
bfqg = blkg_to_bfqg(blkg);
- if (bfqg->online) {
+ if (bfqg->pd.online) {
bio_associate_blkg_from_css(bio, &blkg->blkcg->css);
return bfqg;
}
@@ -985,7 +984,6 @@ static void bfq_pd_offline(struct blkg_policy_data *pd)
put_async_queues:
bfq_put_async_queues(bfqd, bfqg);
- bfqg->online = false;
spin_unlock_irqrestore(&bfqd->lock, flags);
/*
diff --git a/block/bfq-iosched.h b/block/bfq-iosched.h
index 75cc6a324267..69aaee52285a 100644
--- a/block/bfq-iosched.h
+++ b/block/bfq-iosched.h
@@ -1009,8 +1009,6 @@ struct bfq_group {
/* reference counter (see comments in bfq_bic_update_cgroup) */
refcount_t ref;
- /* Is bfq_group still online? */
- bool online;
struct bfq_entity entity;
struct bfq_sched_data sched_data;
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index c46778d1f3c2..d8fe607138b9 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -479,9 +479,9 @@ static void blkg_destroy(struct blkcg_gq *blkg)
struct blkcg_policy *pol = blkcg_policy[i];
if (blkg->pd[i] && blkg->pd[i]->online) {
+ blkg->pd[i]->online = false;
if (pol->pd_offline_fn)
pol->pd_offline_fn(blkg->pd[i]);
- blkg->pd[i]->online = false;
}
}