From d99f7b079c2a49b2278fe80192fbca083db87d18 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 8 Oct 2019 11:56:55 +0100 Subject: [PATCH] drm/i915/gt: Flush submission tasklet before waiting/retiring A common bane of ours is arbitrary delays in ksoftirqd processing our submission tasklet. Give the submission tasklet a kick before we wait to avoid those delays eating into a tight timeout. Signed-off-by: Chris Wilson Reviewed-by: Stuart Summers Link: https://patchwork.freedesktop.org/patch/msgid/20191008105655.13256-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_engine.h | 3 +- drivers/gpu/drm/i915/gt/intel_engine_cs.c | 33 +++++++++++++-------- drivers/gpu/drm/i915/gt/intel_gt_requests.c | 12 ++++++++ 3 files changed, 34 insertions(+), 14 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_engine.h b/drivers/gpu/drm/i915/gt/intel_engine.h index c9e8c8ccbd47..d624752f2a92 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine.h +++ b/drivers/gpu/drm/i915/gt/intel_engine.h @@ -407,8 +407,9 @@ static inline void __intel_engine_reset(struct intel_engine_cs *engine, engine->serial++; /* contexts lost */ } -bool intel_engine_is_idle(struct intel_engine_cs *engine); bool intel_engines_are_idle(struct intel_gt *gt); +bool intel_engine_is_idle(struct intel_engine_cs *engine); +void intel_engine_flush_submission(struct intel_engine_cs *engine); void intel_engines_reset_default_submission(struct intel_gt *gt); diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c index 6220b7151bb9..7e2aa7a6bef0 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c @@ -1040,6 +1040,25 @@ static bool ring_is_idle(struct intel_engine_cs *engine) return idle; } +void intel_engine_flush_submission(struct intel_engine_cs *engine) +{ + struct tasklet_struct *t = &engine->execlists.tasklet; + + if (__tasklet_is_scheduled(t)) { + local_bh_disable(); + if (tasklet_trylock(t)) { + /* Must wait for any GPU reset in progress. */ + if (__tasklet_is_enabled(t)) + t->func(t->data); + tasklet_unlock(t); + } + local_bh_enable(); + } + + /* Otherwise flush the tasklet if it was running on another cpu */ + tasklet_unlock_wait(t); +} + /** * intel_engine_is_idle() - Report if the engine has finished process all work * @engine: the intel_engine_cs @@ -1058,21 +1077,9 @@ bool intel_engine_is_idle(struct intel_engine_cs *engine) /* Waiting to drain ELSP? */ if (execlists_active(&engine->execlists)) { - struct tasklet_struct *t = &engine->execlists.tasklet; - synchronize_hardirq(engine->i915->drm.pdev->irq); - local_bh_disable(); - if (tasklet_trylock(t)) { - /* Must wait for any GPU reset in progress. */ - if (__tasklet_is_enabled(t)) - t->func(t->data); - tasklet_unlock(t); - } - local_bh_enable(); - - /* Otherwise flush the tasklet if it was on another cpu */ - tasklet_unlock_wait(t); + intel_engine_flush_submission(engine); if (execlists_active(&engine->execlists)) return false; diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c index ca606b79fd5e..cbb4069b11e1 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -4,6 +4,7 @@ * Copyright © 2019 Intel Corporation */ +#include "i915_drv.h" /* for_each_engine() */ #include "i915_request.h" #include "intel_gt.h" #include "intel_gt_pm.h" @@ -19,6 +20,15 @@ static void retire_requests(struct intel_timeline *tl) break; } +static void flush_submission(struct intel_gt *gt) +{ + struct intel_engine_cs *engine; + enum intel_engine_id id; + + for_each_engine(engine, gt->i915, id) + intel_engine_flush_submission(engine); +} + long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) { struct intel_gt_timelines *timelines = >->timelines; @@ -32,6 +42,8 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) if (unlikely(timeout < 0)) timeout = -timeout, interruptible = false; + flush_submission(gt); /* kick the ksoftirqd tasklets */ + spin_lock_irqsave(&timelines->lock, flags); list_for_each_entry_safe(tl, tn, &timelines->active_list, link) { if (!mutex_trylock(&tl->mutex)) { -- 2.30.2