[PATCH 06/27] blk-iocost: move iocg_kick_delay() above iocg_kick_waitq()

From: Tejun Heo
Date: Tue Sep 01 2020 - 14:56:34 EST


We'll make iocg_kick_waitq() call iocg_kick_delay(). Reorder them in
preparation. This is pure code reorganization.

Signed-off-by: Tejun Heo <tj@xxxxxxxxxx>
---
block/blk-iocost.c | 120 ++++++++++++++++++++++-----------------------
1 file changed, 60 insertions(+), 60 deletions(-)

diff --git a/block/blk-iocost.c b/block/blk-iocost.c
index 8dfe73dde2a8..ac22d761a350 100644
--- a/block/blk-iocost.c
+++ b/block/blk-iocost.c
@@ -1115,6 +1115,66 @@ static bool iocg_activate(struct ioc_gq *iocg, struct ioc_now *now)
return false;
}

+static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now)
+{
+ struct ioc *ioc = iocg->ioc;
+ struct blkcg_gq *blkg = iocg_to_blkg(iocg);
+ u64 vtime = atomic64_read(&iocg->vtime);
+ u64 vmargin = ioc->margin_us * now->vrate;
+ u64 margin_ns = ioc->margin_us * NSEC_PER_USEC;
+ u64 delta_ns, expires, oexpires;
+ u32 hw_inuse;
+
+ lockdep_assert_held(&iocg->waitq.lock);
+
+ /* debt-adjust vtime */
+ current_hweight(iocg, NULL, &hw_inuse);
+ vtime += abs_cost_to_cost(iocg->abs_vdebt, hw_inuse);
+
+ /*
+ * Clear or maintain depending on the overage. Non-zero vdebt is what
+ * guarantees that @iocg is online and future iocg_kick_delay() will
+ * clear use_delay. Don't leave it on when there's no vdebt.
+ */
+ if (!iocg->abs_vdebt || time_before_eq64(vtime, now->vnow)) {
+ blkcg_clear_delay(blkg);
+ return false;
+ }
+ if (!atomic_read(&blkg->use_delay) &&
+ time_before_eq64(vtime, now->vnow + vmargin))
+ return false;
+
+ /* use delay */
+ delta_ns = DIV64_U64_ROUND_UP(vtime - now->vnow,
+ now->vrate) * NSEC_PER_USEC;
+ blkcg_set_delay(blkg, delta_ns);
+ expires = now->now_ns + delta_ns;
+
+ /* if already active and close enough, don't bother */
+ oexpires = ktime_to_ns(hrtimer_get_softexpires(&iocg->delay_timer));
+ if (hrtimer_is_queued(&iocg->delay_timer) &&
+ abs(oexpires - expires) <= margin_ns / 4)
+ return true;
+
+ hrtimer_start_range_ns(&iocg->delay_timer, ns_to_ktime(expires),
+ margin_ns / 4, HRTIMER_MODE_ABS);
+ return true;
+}
+
+static enum hrtimer_restart iocg_delay_timer_fn(struct hrtimer *timer)
+{
+ struct ioc_gq *iocg = container_of(timer, struct ioc_gq, delay_timer);
+ struct ioc_now now;
+ unsigned long flags;
+
+ spin_lock_irqsave(&iocg->waitq.lock, flags);
+ ioc_now(iocg->ioc, &now);
+ iocg_kick_delay(iocg, &now);
+ spin_unlock_irqrestore(&iocg->waitq.lock, flags);
+
+ return HRTIMER_NORESTART;
+}
+
static int iocg_wake_fn(struct wait_queue_entry *wq_entry, unsigned mode,
int flags, void *key)
{
@@ -1211,66 +1271,6 @@ static enum hrtimer_restart iocg_waitq_timer_fn(struct hrtimer *timer)
return HRTIMER_NORESTART;
}

-static bool iocg_kick_delay(struct ioc_gq *iocg, struct ioc_now *now)
-{
- struct ioc *ioc = iocg->ioc;
- struct blkcg_gq *blkg = iocg_to_blkg(iocg);
- u64 vtime = atomic64_read(&iocg->vtime);
- u64 vmargin = ioc->margin_us * now->vrate;
- u64 margin_ns = ioc->margin_us * NSEC_PER_USEC;
- u64 delta_ns, expires, oexpires;
- u32 hw_inuse;
-
- lockdep_assert_held(&iocg->waitq.lock);
-
- /* debt-adjust vtime */
- current_hweight(iocg, NULL, &hw_inuse);
- vtime += abs_cost_to_cost(iocg->abs_vdebt, hw_inuse);
-
- /*
- * Clear or maintain depending on the overage. Non-zero vdebt is what
- * guarantees that @iocg is online and future iocg_kick_delay() will
- * clear use_delay. Don't leave it on when there's no vdebt.
- */
- if (!iocg->abs_vdebt || time_before_eq64(vtime, now->vnow)) {
- blkcg_clear_delay(blkg);
- return false;
- }
- if (!atomic_read(&blkg->use_delay) &&
- time_before_eq64(vtime, now->vnow + vmargin))
- return false;
-
- /* use delay */
- delta_ns = DIV64_U64_ROUND_UP(vtime - now->vnow,
- now->vrate) * NSEC_PER_USEC;
- blkcg_set_delay(blkg, delta_ns);
- expires = now->now_ns + delta_ns;
-
- /* if already active and close enough, don't bother */
- oexpires = ktime_to_ns(hrtimer_get_softexpires(&iocg->delay_timer));
- if (hrtimer_is_queued(&iocg->delay_timer) &&
- abs(oexpires - expires) <= margin_ns / 4)
- return true;
-
- hrtimer_start_range_ns(&iocg->delay_timer, ns_to_ktime(expires),
- margin_ns / 4, HRTIMER_MODE_ABS);
- return true;
-}
-
-static enum hrtimer_restart iocg_delay_timer_fn(struct hrtimer *timer)
-{
- struct ioc_gq *iocg = container_of(timer, struct ioc_gq, delay_timer);
- struct ioc_now now;
- unsigned long flags;
-
- spin_lock_irqsave(&iocg->waitq.lock, flags);
- ioc_now(iocg->ioc, &now);
- iocg_kick_delay(iocg, &now);
- spin_unlock_irqrestore(&iocg->waitq.lock, flags);
-
- return HRTIMER_NORESTART;
-}
-
static void ioc_lat_stat(struct ioc *ioc, u32 *missed_ppm_ar, u32 *rq_wait_pct_p)
{
u32 nr_met[2] = { };
--
2.26.2