diff options
Diffstat (limited to 'block/blk-iocost.c')
-rw-r--r-- | block/blk-iocost.c | 35 |
1 files changed, 28 insertions, 7 deletions
diff --git a/block/blk-iocost.c b/block/blk-iocost.c index d083f7704082..ef287c33d6d9 100644 --- a/block/blk-iocost.c +++ b/block/blk-iocost.c @@ -1377,7 +1377,7 @@ static void ioc_timer_fn(struct timer_list *timer) * 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 && + if (!waitqueue_active(&iocg->waitq) && !iocg->abs_vdebt && !iocg_is_idle(iocg)) continue; @@ -1546,19 +1546,39 @@ skip_surplus_transfers: if (rq_wait_pct > RQ_WAIT_BUSY_PCT || missed_ppm[READ] > ppm_rthr || missed_ppm[WRITE] > ppm_wthr) { + /* clearly missing QoS targets, slow down vrate */ ioc->busy_level = max(ioc->busy_level, 0); ioc->busy_level++; } else if (rq_wait_pct <= RQ_WAIT_BUSY_PCT * UNBUSY_THR_PCT / 100 && missed_ppm[READ] <= ppm_rthr * UNBUSY_THR_PCT / 100 && missed_ppm[WRITE] <= ppm_wthr * UNBUSY_THR_PCT / 100) { - /* take action iff there is contention */ - if (nr_shortages && !nr_lagging) { + /* QoS targets are being met with >25% margin */ + if (nr_shortages) { + /* + * We're throttling while the device has spare + * capacity. If vrate was being slowed down, stop. + */ ioc->busy_level = min(ioc->busy_level, 0); - /* redistribute surpluses first */ - if (!nr_surpluses) + + /* + * If there are IOs spanning multiple periods, wait + * them out before pushing the device harder. If + * there are surpluses, let redistribution work it + * out first. + */ + if (!nr_lagging && !nr_surpluses) ioc->busy_level--; + } else { + /* + * Nobody is being throttled and the users aren't + * issuing enough IOs to saturate the device. We + * simply don't know how close the device is to + * saturation. Coast. + */ + ioc->busy_level = 0; } } else { + /* inside the hysterisis margin, we're good */ ioc->busy_level = 0; } @@ -2054,14 +2074,15 @@ static void ioc_pd_free(struct blkg_policy_data *pd) { struct ioc_gq *iocg = pd_to_iocg(pd); struct ioc *ioc = iocg->ioc; + unsigned long flags; if (ioc) { - spin_lock(&ioc->lock); + spin_lock_irqsave(&ioc->lock, flags); if (!list_empty(&iocg->active_list)) { propagate_active_weight(iocg, 0, 0); list_del_init(&iocg->active_list); } - spin_unlock(&ioc->lock); + spin_unlock_irqrestore(&ioc->lock, flags); hrtimer_cancel(&iocg->waitq_timer); hrtimer_cancel(&iocg->delay_timer); |