[PATCH 5/5] Revert "blk-cgroup: pin the gendisk in struct blkcg_gq"

Christoph Hellwig
2023-02-14T18:33:08Z

This reverts commit 84d7d462b16dd5f0bf7c7ca9254bf81db2c952a2.

Signed-off-by: Christoph Hellwig <hch-jcswGhMUV9g@public.gmane.org>
---
block/bfq-cgroup.c | 6 +++---
block/blk-cgroup-rwstat.c | 2 +-
block/blk-cgroup.c | 35 ++++++++++++++++++-----------------
block/blk-cgroup.h | 11 ++++++-----
block/blk-iocost.c | 2 +-
block/blk-iolatency.c | 4 ++--
block/blk-throttle.c | 4 ++--
7 files changed, 33 insertions(+), 31 deletions(-)

diff --git a/block/bfq-cgroup.c b/block/bfq-cgroup.c
index 935a497b5dedb3..ea3638e06e04b4 100644
--- a/block/bfq-cgroup.c
+++ b/block/bfq-cgroup.c
@@ -405,7 +405,7 @@ static void bfqg_stats_xfer_dead(struct bfq_group *bfqg)

parent = bfqg_parent(bfqg);

- lockdep_assert_held(&bfqg_to_blkg(bfqg)->disk->queue->queue_lock);
+ lockdep_assert_held(&bfqg_to_blkg(bfqg)->q->queue_lock);

if (unlikely(!parent))
return;
@@ -536,7 +536,7 @@ static void bfq_pd_init(struct blkg_policy_data *pd)
{
struct blkcg_gq *blkg = pd_to_blkg(pd);
struct bfq_group *bfqg = blkg_to_bfqg(blkg);
- struct bfq_data *bfqd = blkg->disk->queue->elevator->elevator_data;
+ struct bfq_data *bfqd = blkg->q->elevator->elevator_data;
struct bfq_entity *entity = &bfqg->entity;
struct bfq_group_data *d = blkcg_to_bfqgd(blkg->blkcg);

@@ -1199,7 +1199,7 @@ static u64 bfqg_prfill_stat_recursive(struct seq_file *sf,
struct cgroup_subsys_state *pos_css;
u64 sum = 0;

- lockdep_assert_held(&blkg->disk->queue->queue_lock);
+ lockdep_assert_held(&blkg->q->queue_lock);

rcu_read_lock();
blkg_for_each_descendant_pre(pos_blkg, pos_css, blkg) {
diff --git a/block/blk-cgroup-rwstat.c b/block/blk-cgroup-rwstat.c
index b8b8c82e667a3b..3304e841df7ce9 100644
--- a/block/blk-cgroup-rwstat.c
+++ b/block/blk-cgroup-rwstat.c
@@ -107,7 +107,7 @@ void blkg_rwstat_recursive_sum(struct blkcg_gq *blkg, struct blkcg_policy *pol,
struct cgroup_subsys_state *pos_css;
unsigned int i;

- lockdep_assert_held(&blkg->disk->queue->queue_lock);
+ lockdep_assert_held(&blkg->q->queue_lock);

memset(sum, 0, sizeof(*sum));
rcu_read_lock();
diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index 1574566321245e..981ebe003b1c63 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -118,6 +118,7 @@ static void blkg_free_workfn(struct work_struct *work)
{
struct blkcg_gq *blkg = container_of(work, struct blkcg_gq,
free_work);
+ struct request_queue *q = blkg->q;
int i;

/*
@@ -127,16 +128,16 @@ static void blkg_free_workfn(struct work_struct *work)
* blkcg_mutex is used to synchronize blkg_free_workfn() and
* blkcg_deactivate_policy().
*/
- mutex_lock(&blkg->disk->queue->blkcg_mutex);
+ mutex_lock(&q->blkcg_mutex);
for (i = 0; i < BLKCG_MAX_POLS; i++)
if (blkg->pd[i])
blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
if (blkg->parent)
blkg_put(blkg->parent);
list_del_init(&blkg->q_node);
- mutex_unlock(&blkg->disk->queue->blkcg_mutex);
+ mutex_unlock(&q->blkcg_mutex);

- put_disk(blkg->disk);
+ blk_put_queue(q);
free_percpu(blkg->iostat_cpu);
percpu_ref_exit(&blkg->refcnt);
kfree(blkg);
@@ -263,12 +264,10 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk,
blkg->iostat_cpu = alloc_percpu_gfp(struct blkg_iostat_set, gfp_mask);
if (!blkg->iostat_cpu)
goto out_exit_refcnt;
-
- if (test_bit(GD_DEAD, &disk->state))
+ if (!blk_get_queue(disk->queue))
goto out_free_iostat;
- get_device(disk_to_dev(disk));
- blkg->disk = disk;

+ blkg->q = disk->queue;
INIT_LIST_HEAD(&blkg->q_node);
spin_lock_init(&blkg->async_bio_lock);
bio_list_init(&blkg->async_bios);
@@ -304,7 +303,7 @@ static struct blkcg_gq *blkg_alloc(struct blkcg *blkcg, struct gendisk *disk,
while (--i >= 0)
if (blkg->pd[i])
blkcg_policy[i]->pd_free_fn(blkg->pd[i]);
- put_disk(blkg->disk);
+ blk_put_queue(disk->queue);
out_free_iostat:
free_percpu(blkg->iostat_cpu);
out_exit_refcnt:
@@ -476,7 +475,7 @@ static void blkg_destroy(struct blkcg_gq *blkg)
struct blkcg *blkcg = blkg->blkcg;
int i;

- lockdep_assert_held(&blkg->disk->queue->queue_lock);
+ lockdep_assert_held(&blkg->q->queue_lock);
lockdep_assert_held(&blkcg->lock);

/*
@@ -500,7 +499,7 @@ static void blkg_destroy(struct blkcg_gq *blkg)

blkg->online = false;

- radix_tree_delete(&blkcg->blkg_tree, blkg->disk->queue->id);
+ radix_tree_delete(&blkcg->blkg_tree, blkg->q->id);
hlist_del_init_rcu(&blkg->blkcg_node);

/*
@@ -587,7 +586,9 @@ static int blkcg_reset_stats(struct cgroup_subsys_state *css,

const char *blkg_dev_name(struct blkcg_gq *blkg)
{
- return bdi_dev_name(blkg->disk->bdi);
+ if (!blkg->q->disk)
+ return NULL;
+ return bdi_dev_name(blkg->q->disk->bdi);
}

/**
@@ -619,10 +620,10 @@ void blkcg_print_blkgs(struct seq_file *sf, struct blkcg *blkcg,

rcu_read_lock();
hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) {
- spin_lock_irq(&blkg->disk->queue->queue_lock);
- if (blkcg_policy_enabled(blkg->disk->queue, pol))
+ spin_lock_irq(&blkg->q->queue_lock);
+ if (blkcg_policy_enabled(blkg->q, pol))
total += prfill(sf, blkg->pd[pol->plid], data);
- spin_unlock_irq(&blkg->disk->queue->queue_lock);
+ spin_unlock_irq(&blkg->q->queue_lock);
}
rcu_read_unlock();

@@ -1046,9 +1047,9 @@ static int blkcg_print_stat(struct seq_file *sf, void *v)

rcu_read_lock();
hlist_for_each_entry_rcu(blkg, &blkcg->blkg_list, blkcg_node) {
- spin_lock_irq(&blkg->disk->queue->queue_lock);
+ spin_lock_irq(&blkg->q->queue_lock);
blkcg_print_one_stat(blkg, sf);
- spin_unlock_irq(&blkg->disk->queue->queue_lock);
+ spin_unlock_irq(&blkg->q->queue_lock);
}
rcu_read_unlock();
return 0;
@@ -1118,7 +1119,7 @@ static void blkcg_destroy_blkgs(struct blkcg *blkcg)
while (!hlist_empty(&blkcg->blkg_list)) {
struct blkcg_gq *blkg = hlist_entry(blkcg->blkg_list.first,
struct blkcg_gq, blkcg_node);
- struct request_queue *q = blkg->disk->queue;
+ struct request_queue *q = blkg->q;

if (need_resched() || !spin_trylock(&q->queue_lock)) {
/*
diff --git a/block/blk-cgroup.h b/block/blk-cgroup.h
index 3d9e42c519db86..9c5078755e5e19 100644
--- a/block/blk-cgroup.h
+++ b/block/blk-cgroup.h
@@ -53,7 +53,8 @@ struct blkg_iostat_set {

/* association between a blk cgroup and a request queue */
struct blkcg_gq {
- struct gendisk *disk;
+ /* Pointer to the associated request_queue */
+ struct request_queue *q;
struct list_head q_node;
struct hlist_node blkcg_node;
struct blkcg *blkcg;
@@ -253,11 +254,11 @@ static inline struct blkcg_gq *blkg_lookup(struct blkcg *blkcg,
return q->root_blkg;

blkg = rcu_dereference(blkcg->blkg_hint);
- if (blkg && blkg->disk->queue == q)
+ if (blkg && blkg->q == q)
return blkg;

blkg = radix_tree_lookup(&blkcg->blkg_tree, q->id);
- if (blkg && blkg->disk->queue != q)
+ if (blkg && blkg->q != q)
blkg = NULL;
return blkg;
}
@@ -357,7 +358,7 @@ static inline void blkg_put(struct blkcg_gq *blkg)
#define blkg_for_each_descendant_pre(d_blkg, pos_css, p_blkg) \
css_for_each_descendant_pre((pos_css), &(p_blkg)->blkcg->css) \
if (((d_blkg) = blkg_lookup(css_to_blkcg(pos_css), \
- (p_blkg)->disk->queue)))
+ (p_blkg)->q)))

/**
* blkg_for_each_descendant_post - post-order walk of a blkg's descendants
@@ -372,7 +373,7 @@ static inline void blkg_put(struct blkcg_gq *blkg)
#define blkg_for_each_descendant_post(d_blkg, pos_css, p_blkg) \
css_for_each_descendant_post((pos_css), &(p_blkg)->blkcg->css) \
if (((d_blkg) = blkg_lookup(css_to_blkcg(pos_css), \
- (p_blkg)->disk->queue)))
+ (p_blkg)->q)))

bool __blkcg_punt_bio_submit(struct bio *bio);

diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 7a2dc9dc8e3ba0..ff534e9d92dca2 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -2947,7 +2947,7 @@ static void ioc_pd_init(struct blkg_policy_data *pd)
{
struct ioc_gq *iocg = pd_to_iocg(pd);
struct blkcg_gq *blkg = pd_to_blkg(&iocg->pd);
- struct ioc *ioc = q_to_ioc(blkg->disk->queue);
+ struct ioc *ioc = q_to_ioc(blkg->q);
struct ioc_now now;
struct blkcg_gq *tblkg;
unsigned long flags;
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c
index bc0d217f5c1723..0dc910568b3145 100644
--- a/block/blk-iolatency.c
+++ b/block/blk-iolatency.c
@@ -967,12 +967,12 @@ static void iolatency_pd_init(struct blkg_policy_data *pd)
{
struct iolatency_grp *iolat = pd_to_lat(pd);
struct blkcg_gq *blkg = lat_to_blkg(iolat);
- struct rq_qos *rqos = blkcg_rq_qos(blkg->disk->queue);
+ struct rq_qos *rqos = blkcg_rq_qos(blkg->q);
struct blk_iolatency *blkiolat = BLKIOLATENCY(rqos);
u64 now = ktime_to_ns(ktime_get());
int cpu;

- if (blk_queue_nonrot(blkg->disk->queue))
+ if (blk_queue_nonrot(blkg->q))
iolat->ssd = true;
else
iolat->ssd = false;
diff --git a/block/blk-throttle.c b/block/blk-throttle.c
index 74bb1e753ea09d..47e9d8be68f300 100644
--- a/block/blk-throttle.c
+++ b/block/blk-throttle.c
@@ -387,7 +387,7 @@ static void throtl_pd_init(struct blkg_policy_data *pd)
{
struct throtl_grp *tg = pd_to_tg(pd);
struct blkcg_gq *blkg = tg_to_blkg(tg);
- struct throtl_data *td = blkg->disk->queue->td;
+ struct throtl_data *td = blkg->q->td;
struct throtl_service_queue *sq = &tg->service_queue;

/*
@@ -1174,7 +1174,7 @@ static void throtl_pending_timer_fn(struct timer_list *t)

/* throtl_data may be gone, so figure out request queue by blkg */
if (tg)
- q = tg->pd.blkg->disk->queue;
+ q = tg->pd.blkg->q;
else
q = td->queue;

--
2.39.1