From 88cec4973de1d096282565779bbd9d5c6412a293 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 20 Nov 2019 17:08:58 +0000 Subject: [PATCH] drm/i915/gt: Declare timeline.lock to be irq-free Now that we never allow the intel_wakeref callbacks to be invoked from interrupt context, we do not need the irqsafe spinlock for the timeline. Signed-off-by: Chris Wilson Reviewed-by: Tvrtko Ursulin Link: https://patchwork.freedesktop.org/patch/msgid/20191120170858.3965380-1-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/gt/intel_gt_requests.c | 9 ++++----- drivers/gpu/drm/i915/gt/intel_reset.c | 9 ++++----- drivers/gpu/drm/i915/gt/intel_timeline.c | 10 ++++------ 3 files changed, 12 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/i915/gt/intel_gt_requests.c b/drivers/gpu/drm/i915/gt/intel_gt_requests.c index 1a005da8c588..4dc3cbeb1b36 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_requests.c +++ b/drivers/gpu/drm/i915/gt/intel_gt_requests.c @@ -33,7 +33,6 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) { struct intel_gt_timelines *timelines = >->timelines; struct intel_timeline *tl, *tn; - unsigned long flags; bool interruptible; LIST_HEAD(free); @@ -43,7 +42,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) flush_submission(gt); /* kick the ksoftirqd tasklets */ - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); list_for_each_entry_safe(tl, tn, &timelines->active_list, link) { if (!mutex_trylock(&tl->mutex)) continue; @@ -51,7 +50,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) intel_timeline_get(tl); GEM_BUG_ON(!atomic_read(&tl->active_count)); atomic_inc(&tl->active_count); /* pin the list element */ - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); if (timeout > 0) { struct dma_fence *fence; @@ -67,7 +66,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) retire_requests(tl); - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); /* Resume iteration after dropping lock */ list_safe_reset_next(tl, tn, link); @@ -82,7 +81,7 @@ long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout) list_add(&tl->link, &free); } } - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); list_for_each_entry_safe(tl, tn, &free, link) __intel_timeline_free(&tl->kref); diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c index 0388f9375366..36189238e13c 100644 --- a/drivers/gpu/drm/i915/gt/intel_reset.c +++ b/drivers/gpu/drm/i915/gt/intel_reset.c @@ -831,7 +831,6 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) { struct intel_gt_timelines *timelines = >->timelines; struct intel_timeline *tl; - unsigned long flags; bool ok; if (!test_bit(I915_WEDGED, >->reset.flags)) @@ -853,7 +852,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) * * No more can be submitted until we reset the wedged bit. */ - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); list_for_each_entry(tl, &timelines->active_list, link) { struct dma_fence *fence; @@ -861,7 +860,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) if (!fence) continue; - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); /* * All internal dependencies (i915_requests) will have @@ -874,10 +873,10 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) dma_fence_put(fence); /* Restart iteration after droping lock */ - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); tl = list_entry(&timelines->active_list, typeof(*tl), link); } - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); /* We must reset pending GPU events before restoring our submission */ ok = !HAS_EXECLISTS(gt->i915); /* XXX better agnosticism desired */ diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c index b35f12729983..b190a5d9ab02 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.c +++ b/drivers/gpu/drm/i915/gt/intel_timeline.c @@ -332,7 +332,6 @@ int intel_timeline_pin(struct intel_timeline *tl) void intel_timeline_enter(struct intel_timeline *tl) { struct intel_gt_timelines *timelines = &tl->gt->timelines; - unsigned long flags; /* * Pretend we are serialised by the timeline->mutex. @@ -358,16 +357,15 @@ void intel_timeline_enter(struct intel_timeline *tl) if (atomic_add_unless(&tl->active_count, 1, 0)) return; - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); if (!atomic_fetch_inc(&tl->active_count)) list_add_tail(&tl->link, &timelines->active_list); - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); } void intel_timeline_exit(struct intel_timeline *tl) { struct intel_gt_timelines *timelines = &tl->gt->timelines; - unsigned long flags; /* See intel_timeline_enter() */ lockdep_assert_held(&tl->mutex); @@ -376,10 +374,10 @@ void intel_timeline_exit(struct intel_timeline *tl) if (atomic_add_unless(&tl->active_count, -1, 1)) return; - spin_lock_irqsave(&timelines->lock, flags); + spin_lock(&timelines->lock); if (atomic_dec_and_test(&tl->active_count)) list_del(&tl->link); - spin_unlock_irqrestore(&timelines->lock, flags); + spin_unlock(&timelines->lock); /* * Since this timeline is idle, all bariers upon which we were waiting -- 2.30.2