* [PATCH -next v3] block, bfq: cleanup 'bfqg->online'
@ 2023-02-02 13:49 ` Yu Kuai
0 siblings, 0 replies; 4+ messages in thread
From: Yu Kuai @ 2023-02-02 13:49 UTC (permalink / raw)
To: jack, paolo.valente, axboe, tj, josef
Cc: linux-block, cgroups, linux-kernel, yukuai3, yukuai1, yi.zhang,
yangerkun
From: Yu Kuai <yukuai3@huawei.com>
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>
---
Changes in v3:
- in commit message: protected -> not protected, bfq_pd_offline_() ->
bfq_pd_offline().
Changes in v2:
- clear 'pd->online' before calling bfq_pd_offline()
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 b42956ab5550..a35136dae713 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 cb110fc51940..a228dfe65253 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -491,9 +491,9 @@ 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;
}
}
--
2.31.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* [PATCH -next v3] block, bfq: cleanup 'bfqg->online'
@ 2023-02-02 13:49 ` Yu Kuai
0 siblings, 0 replies; 4+ messages in thread
From: Yu Kuai @ 2023-02-02 13:49 UTC (permalink / raw)
To: jack-AlSwsSmVLrQ, paolo.valente-QSEj5FYQhm4dnm+yROfE0A,
axboe-tSWWG44O7X1aa/9Udqfwiw, tj-DgEjT+Ai2ygdnm+yROfE0A,
josef-DigfWCa+lFGyeJad7bwFQA
Cc: linux-block-u79uwXL29TY76Z2rM5mHXA,
cgroups-u79uwXL29TY76Z2rM5mHXA,
linux-kernel-u79uwXL29TY76Z2rM5mHXA,
yukuai3-hv44wF8Li93QT0dZR+AlfA, yukuai1-XF6JlduFytWkHkcT6e4Xnw,
yi.zhang-hv44wF8Li93QT0dZR+AlfA,
yangerkun-hv44wF8Li93QT0dZR+AlfA
From: Yu Kuai <yukuai3-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
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-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>
---
Changes in v3:
- in commit message: protected -> not protected, bfq_pd_offline_() ->
bfq_pd_offline().
Changes in v2:
- clear 'pd->online' before calling bfq_pd_offline()
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 b42956ab5550..a35136dae713 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 cb110fc51940..a228dfe65253 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -491,9 +491,9 @@ 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;
}
}
--
2.31.1
^ permalink raw reply related [flat|nested] 4+ messages in thread* Re: [PATCH -next v3] block, bfq: cleanup 'bfqg->online'
2023-02-02 13:49 ` Yu Kuai
(?)
@ 2023-02-07 10:07 ` Jan Kara
-1 siblings, 0 replies; 4+ messages in thread
From: Jan Kara @ 2023-02-07 10:07 UTC (permalink / raw)
To: Yu Kuai
Cc: jack, paolo.valente, axboe, tj, josef, linux-block, cgroups,
linux-kernel, yukuai3, yi.zhang, yangerkun
On Thu 02-02-23 21:49:13, Yu Kuai wrote:
> From: Yu Kuai <yukuai3@huawei.com>
>
> 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>
The patch looks good to me now. Thanks! Feel free to add:
Reviewed-by: Jan Kara <jack@suse.cz>
Honza
> ---
> Changes in v3:
> - in commit message: protected -> not protected, bfq_pd_offline_() ->
> bfq_pd_offline().
> Changes in v2:
> - clear 'pd->online' before calling bfq_pd_offline()
>
> 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 b42956ab5550..a35136dae713 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 cb110fc51940..a228dfe65253 100644
> --- a/block/blk-cgroup.c
> +++ b/block/blk-cgroup.c
> @@ -491,9 +491,9 @@ 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;
> }
> }
>
> --
> 2.31.1
>
--
Jan Kara <jack@suse.com>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 4+ messages in thread* Re: [PATCH -next v3] block, bfq: cleanup 'bfqg->online'
2023-02-02 13:49 ` Yu Kuai
(?)
(?)
@ 2023-02-07 17:21 ` Jens Axboe
-1 siblings, 0 replies; 4+ messages in thread
From: Jens Axboe @ 2023-02-07 17:21 UTC (permalink / raw)
To: jack, paolo.valente, tj, josef, Yu Kuai
Cc: linux-block, cgroups, linux-kernel, yukuai3, yi.zhang, yangerkun
On Thu, 02 Feb 2023 21:49:13 +0800, Yu Kuai wrote:
> 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.
>
> [...]
Applied, thanks!
[1/1] block, bfq: cleanup 'bfqg->online'
commit: f37bf75ca73d523ebaa7ceb44c45d8ecd05374fe
Best regards,
--
Jens Axboe
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2023-02-07 17:21 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2023-02-02 13:49 [PATCH -next v3] block, bfq: cleanup 'bfqg->online' Yu Kuai
2023-02-02 13:49 ` Yu Kuai
2023-02-07 10:07 ` Jan Kara
2023-02-07 17:21 ` Jens Axboe
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