diff options
author | Chris Wilson <chris@chris-wilson.co.uk> | 2019-08-23 14:26:46 +0100 |
---|---|---|
committer | Rodrigo Vivi <rodrigo.vivi@intel.com> | 2019-09-06 09:53:07 -0700 |
commit | ff36c5c4fd0b3783ed982ecf292a42d20c2f2725 (patch) | |
tree | 424e0a107e7269bb6a371eee042dacdf693cadf6 /drivers/gpu/drm/i915/gt | |
parent | 0ac072cced08390b9b31fe3c56c364c3ef2f6d6a (diff) |
drm/i915: Hold irq-off for the entire fake lock period
Sadly lockdep records when the irqs are re-enabled and then marks up the
fake lock as being irq-unsafe. Our hand is forced and so we must mark up
the entire fake lock critical section as irq-off.
Hopefully this is the last tweak required!
v2: Not quite, we need to mark the timeline spinlock as irqsafe. That
was a genuine bug being hidden by the earlier lockdep splat.
Fixes: d67739268cf0 ("drm/i915/gt: Mark up the nested engine-pm timeline lock as irqsafe")
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190823132700.25286-2-chris@chris-wilson.co.uk
(cherry picked from commit 6dcb85a0ad990455ae7c596e3fc966ad9c1ba9c5)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/gt')
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_engine_pm.c | 28 | ||||
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_reset.c | 9 | ||||
-rw-r--r-- | drivers/gpu/drm/i915/gt/intel_timeline.c | 10 |
3 files changed, 29 insertions, 18 deletions
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c index a372d4ea9370..65b5ca74b394 100644 --- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c +++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c @@ -39,27 +39,32 @@ static int __engine_unpark(struct intel_wakeref *wf) #if IS_ENABLED(CONFIG_LOCKDEP) -static inline void __timeline_mark_lock(struct intel_context *ce) +static inline unsigned long __timeline_mark_lock(struct intel_context *ce) { unsigned long flags; local_irq_save(flags); mutex_acquire(&ce->timeline->mutex.dep_map, 2, 0, _THIS_IP_); - local_irq_restore(flags); + + return flags; } -static inline void __timeline_mark_unlock(struct intel_context *ce) +static inline void __timeline_mark_unlock(struct intel_context *ce, + unsigned long flags) { mutex_release(&ce->timeline->mutex.dep_map, 0, _THIS_IP_); + local_irq_restore(flags); } #else -static inline void __timeline_mark_lock(struct intel_context *ce) +static inline unsigned long __timeline_mark_lock(struct intel_context *ce) { + return 0; } -static inline void __timeline_mark_unlock(struct intel_context *ce) +static inline void __timeline_mark_unlock(struct intel_context *ce, + unsigned long flags) { } @@ -68,6 +73,8 @@ static inline void __timeline_mark_unlock(struct intel_context *ce) static bool switch_to_kernel_context(struct intel_engine_cs *engine) { struct i915_request *rq; + unsigned long flags; + bool result = true; /* Already inside the kernel context, safe to power down. */ if (engine->wakeref_serial == engine->serial) @@ -89,12 +96,12 @@ static bool switch_to_kernel_context(struct intel_engine_cs *engine) * retiring the last request, thus all rings should be empty and * all timelines idle. */ - __timeline_mark_lock(engine->kernel_context); + flags = __timeline_mark_lock(engine->kernel_context); rq = __i915_request_create(engine->kernel_context, GFP_NOWAIT); if (IS_ERR(rq)) /* Context switch failed, hope for the best! Maybe reset? */ - return true; + goto out_unlock; intel_timeline_enter(rq->timeline); @@ -110,9 +117,10 @@ static bool switch_to_kernel_context(struct intel_engine_cs *engine) __intel_wakeref_defer_park(&engine->wakeref); __i915_request_queue(rq, NULL); - __timeline_mark_unlock(engine->kernel_context); - - return false; + result = false; +out_unlock: + __timeline_mark_unlock(engine->kernel_context, flags); + return result; } static int __engine_park(struct intel_wakeref *wf) diff --git a/drivers/gpu/drm/i915/gt/intel_reset.c b/drivers/gpu/drm/i915/gt/intel_reset.c index 077716442c90..b9d84d52e986 100644 --- a/drivers/gpu/drm/i915/gt/intel_reset.c +++ b/drivers/gpu/drm/i915/gt/intel_reset.c @@ -792,6 +792,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) { struct intel_gt_timelines *timelines = >->timelines; struct intel_timeline *tl; + unsigned long flags; if (!test_bit(I915_WEDGED, >->reset.flags)) return true; @@ -811,7 +812,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) * * No more can be submitted until we reset the wedged bit. */ - spin_lock(&timelines->lock); + spin_lock_irqsave(&timelines->lock, flags); list_for_each_entry(tl, &timelines->active_list, link) { struct i915_request *rq; @@ -819,7 +820,7 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) if (!rq) continue; - spin_unlock(&timelines->lock); + spin_unlock_irqrestore(&timelines->lock, flags); /* * All internal dependencies (i915_requests) will have @@ -832,10 +833,10 @@ static bool __intel_gt_unset_wedged(struct intel_gt *gt) i915_request_put(rq); /* Restart iteration after droping lock */ - spin_lock(&timelines->lock); + spin_lock_irqsave(&timelines->lock, flags); tl = list_entry(&timelines->active_list, typeof(*tl), link); } - spin_unlock(&timelines->lock); + spin_unlock_irqrestore(&timelines->lock, flags); intel_gt_sanitize(gt, false); diff --git a/drivers/gpu/drm/i915/gt/intel_timeline.c b/drivers/gpu/drm/i915/gt/intel_timeline.c index 02fbe11b671b..9cb01d9828f1 100644 --- a/drivers/gpu/drm/i915/gt/intel_timeline.c +++ b/drivers/gpu/drm/i915/gt/intel_timeline.c @@ -337,6 +337,7 @@ 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; lockdep_assert_held(&tl->mutex); @@ -345,14 +346,15 @@ void intel_timeline_enter(struct intel_timeline *tl) return; GEM_BUG_ON(!tl->active_count); /* overflow? */ - spin_lock(&timelines->lock); + spin_lock_irqsave(&timelines->lock, flags); list_add(&tl->link, &timelines->active_list); - spin_unlock(&timelines->lock); + spin_unlock_irqrestore(&timelines->lock, flags); } void intel_timeline_exit(struct intel_timeline *tl) { struct intel_gt_timelines *timelines = &tl->gt->timelines; + unsigned long flags; lockdep_assert_held(&tl->mutex); @@ -360,9 +362,9 @@ void intel_timeline_exit(struct intel_timeline *tl) if (--tl->active_count) return; - spin_lock(&timelines->lock); + spin_lock_irqsave(&timelines->lock, flags); list_del(&tl->link); - spin_unlock(&timelines->lock); + spin_unlock_irqrestore(&timelines->lock, flags); /* * Since this timeline is idle, all bariers upon which we were waiting |