blk-throttle: clean up codes that can't be reached

While doing code coverage testing while CONFIG_BLK_DEV_THROTTLING_LOW is
disabled, we found that there are many codes can never be reached.

This patch move such codes inside "#ifdef CONFIG_BLK_DEV_THROTTLING_LOW".

Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20220903062826.1099085-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Yu Kuai 2022-09-03 14:28:26 +08:00 committed by Jens Axboe
parent bce1b56c73
commit 2d8f7a3b9f

View File

@ -1673,6 +1673,40 @@ struct blkcg_policy blkcg_policy_throtl = {
.pd_free_fn = throtl_pd_free,
};
void blk_throtl_cancel_bios(struct request_queue *q)
{
struct cgroup_subsys_state *pos_css;
struct blkcg_gq *blkg;
spin_lock_irq(&q->queue_lock);
/*
* queue_lock is held, rcu lock is not needed here technically.
* However, rcu lock is still held to emphasize that following
* path need RCU protection and to prevent warning from lockdep.
*/
rcu_read_lock();
blkg_for_each_descendant_post(blkg, pos_css, q->root_blkg) {
struct throtl_grp *tg = blkg_to_tg(blkg);
struct throtl_service_queue *sq = &tg->service_queue;
/*
* Set the flag to make sure throtl_pending_timer_fn() won't
* stop until all throttled bios are dispatched.
*/
blkg_to_tg(blkg)->flags |= THROTL_TG_CANCELING;
/*
* Update disptime after setting the above flag to make sure
* throtl_select_dispatch() won't exit without dispatching.
*/
tg_update_disptime(tg);
throtl_schedule_pending_timer(sq, jiffies + 1);
}
rcu_read_unlock();
spin_unlock_irq(&q->queue_lock);
}
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
static unsigned long __tg_last_low_overflow_time(struct throtl_grp *tg)
{
unsigned long rtime = jiffies, wtime = jiffies;
@ -1777,39 +1811,6 @@ static bool throtl_hierarchy_can_upgrade(struct throtl_grp *tg)
return false;
}
void blk_throtl_cancel_bios(struct request_queue *q)
{
struct cgroup_subsys_state *pos_css;
struct blkcg_gq *blkg;
spin_lock_irq(&q->queue_lock);
/*
* queue_lock is held, rcu lock is not needed here technically.
* However, rcu lock is still held to emphasize that following
* path need RCU protection and to prevent warning from lockdep.
*/
rcu_read_lock();
blkg_for_each_descendant_post(blkg, pos_css, q->root_blkg) {
struct throtl_grp *tg = blkg_to_tg(blkg);
struct throtl_service_queue *sq = &tg->service_queue;
/*
* Set the flag to make sure throtl_pending_timer_fn() won't
* stop until all throttled bios are dispatched.
*/
blkg_to_tg(blkg)->flags |= THROTL_TG_CANCELING;
/*
* Update disptime after setting the above flag to make sure
* throtl_select_dispatch() won't exit without dispatching.
*/
tg_update_disptime(tg);
throtl_schedule_pending_timer(sq, jiffies + 1);
}
rcu_read_unlock();
spin_unlock_irq(&q->queue_lock);
}
static bool throtl_can_upgrade(struct throtl_data *td,
struct throtl_grp *this_tg)
{
@ -2005,7 +2006,6 @@ static void blk_throtl_update_idletime(struct throtl_grp *tg)
tg->checked_last_finish_time = last_finish_time;
}
#ifdef CONFIG_BLK_DEV_THROTTLING_LOW
static void throtl_update_latency_buckets(struct throtl_data *td)
{
struct avg_latency_bucket avg_latency[2][LATENCY_BUCKET_SIZE];
@ -2086,6 +2086,28 @@ static void throtl_update_latency_buckets(struct throtl_data *td)
static inline void throtl_update_latency_buckets(struct throtl_data *td)
{
}
static void blk_throtl_update_idletime(struct throtl_grp *tg)
{
}
static void throtl_downgrade_check(struct throtl_grp *tg)
{
}
static void throtl_upgrade_check(struct throtl_grp *tg)
{
}
static bool throtl_can_upgrade(struct throtl_data *td,
struct throtl_grp *this_tg)
{
return false;
}
static void throtl_upgrade_state(struct throtl_data *td)
{
}
#endif
bool __blk_throtl_bio(struct bio *bio)