From 2474787a75b4f358e81f367653c73edecd67aa2d Mon Sep 17 00:00:00 2001 From: Baolin Wang Date: Thu, 26 Nov 2020 16:16:14 +0800 Subject: blk-iocost: Factor out the active iocgs' state check into a separate function Factor out the iocgs' state check into a separate function to simplify the ioc_timer_fn(). No functional change. Signed-off-by: Baolin Wang Acked-by: Tejun Heo Signed-off-by: Jens Axboe --- block/blk-iocost.c | 94 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 54 insertions(+), 40 deletions(-) (limited to 'block') diff --git a/block/blk-iocost.c b/block/blk-iocost.c index 09f22f9a6ba4..7dd1424d5833 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -2069,40 +2069,21 @@ static void ioc_forgive_debts(struct ioc *ioc, u64 usage_us_sum, int nr_debtors, } } -static void ioc_timer_fn(struct timer_list *timer) +/* + * Check the active iocgs' state to avoid oversleeping and deactive + * idle iocgs. + * + * Since waiters determine the sleep durations based on the vrate + * they saw at the time of sleep, if vrate has increased, some + * waiters could be sleeping for too long. Wake up tardy waiters + * which should have woken up in the last period and expire idle + * iocgs. + */ +static int ioc_check_iocgs(struct ioc *ioc, struct ioc_now *now) { - struct ioc *ioc = container_of(timer, struct ioc, timer); + int nr_debtors = 0; struct ioc_gq *iocg, *tiocg; - struct ioc_now now; - LIST_HEAD(surpluses); - int nr_debtors = 0, nr_shortages = 0, nr_lagging = 0; - u64 usage_us_sum = 0; - u32 ppm_rthr = MILLION - ioc->params.qos[QOS_RPPM]; - u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM]; - u32 missed_ppm[2], rq_wait_pct; - u64 period_vtime; - int prev_busy_level; - - /* how were the latencies during the period? */ - ioc_lat_stat(ioc, missed_ppm, &rq_wait_pct); - /* take care of active iocgs */ - spin_lock_irq(&ioc->lock); - - ioc_now(ioc, &now); - - period_vtime = now.vnow - ioc->period_at_vtime; - if (WARN_ON_ONCE(!period_vtime)) { - spin_unlock_irq(&ioc->lock); - return; - } - - /* - * Waiters determine the sleep durations based on the vrate they - * saw at the time of sleep. If vrate has increased, some waiters - * could be sleeping for too long. Wake up tardy waiters which - * should have woken up in the last period and expire idle iocgs. - */ list_for_each_entry_safe(iocg, tiocg, &ioc->active_iocgs, active_list) { if (!waitqueue_active(&iocg->waitq) && !iocg->abs_vdebt && !iocg->delay && !iocg_is_idle(iocg)) @@ -2112,24 +2093,24 @@ static void ioc_timer_fn(struct timer_list *timer) /* flush wait and indebt stat deltas */ if (iocg->wait_since) { - iocg->local_stat.wait_us += now.now - iocg->wait_since; - iocg->wait_since = now.now; + iocg->local_stat.wait_us += now->now - iocg->wait_since; + iocg->wait_since = now->now; } if (iocg->indebt_since) { iocg->local_stat.indebt_us += - now.now - iocg->indebt_since; - iocg->indebt_since = now.now; + now->now - iocg->indebt_since; + iocg->indebt_since = now->now; } if (iocg->indelay_since) { iocg->local_stat.indelay_us += - now.now - iocg->indelay_since; - iocg->indelay_since = now.now; + now->now - iocg->indelay_since; + iocg->indelay_since = now->now; } if (waitqueue_active(&iocg->waitq) || iocg->abs_vdebt || iocg->delay) { /* might be oversleeping vtime / hweight changes, kick */ - iocg_kick_waitq(iocg, true, &now); + iocg_kick_waitq(iocg, true, now); if (iocg->abs_vdebt || iocg->delay) nr_debtors++; } else if (iocg_is_idle(iocg)) { @@ -2143,7 +2124,7 @@ static void ioc_timer_fn(struct timer_list *timer) * error and throw away. On reactivation, it'll start * with the target budget. */ - excess = now.vnow - vtime - ioc->margins.target; + excess = now->vnow - vtime - ioc->margins.target; if (excess > 0) { u32 old_hwi; @@ -2152,13 +2133,46 @@ static void ioc_timer_fn(struct timer_list *timer) WEIGHT_ONE); } - __propagate_weights(iocg, 0, 0, false, &now); + __propagate_weights(iocg, 0, 0, false, now); list_del_init(&iocg->active_list); } spin_unlock(&iocg->waitq.lock); } + commit_weights(ioc); + return nr_debtors; +} + +static void ioc_timer_fn(struct timer_list *timer) +{ + struct ioc *ioc = container_of(timer, struct ioc, timer); + struct ioc_gq *iocg, *tiocg; + struct ioc_now now; + LIST_HEAD(surpluses); + int nr_debtors, nr_shortages = 0, nr_lagging = 0; + u64 usage_us_sum = 0; + u32 ppm_rthr = MILLION - ioc->params.qos[QOS_RPPM]; + u32 ppm_wthr = MILLION - ioc->params.qos[QOS_WPPM]; + u32 missed_ppm[2], rq_wait_pct; + u64 period_vtime; + int prev_busy_level; + + /* how were the latencies during the period? */ + ioc_lat_stat(ioc, missed_ppm, &rq_wait_pct); + + /* take care of active iocgs */ + spin_lock_irq(&ioc->lock); + + ioc_now(ioc, &now); + + period_vtime = now.vnow - ioc->period_at_vtime; + if (WARN_ON_ONCE(!period_vtime)) { + spin_unlock_irq(&ioc->lock); + return; + } + + nr_debtors = ioc_check_iocgs(ioc, &now); /* * Wait and indebt stat are flushed above and the donation calculation -- cgit v1.2.3