On 04/04/2023 17:00, Andi Shyti wrote:
Hi Tvrtko,
diff --git a/drivers/gpu/drm/i915/gt/intel_context.h b/drivers/gpu/drm/i915/gt/intel_context.h
index 0a8d553da3f439..48f888c3da083b 100644
--- a/drivers/gpu/drm/i915/gt/intel_context.h
+++ b/drivers/gpu/drm/i915/gt/intel_context.h
@@ -14,6 +14,7 @@
#include "i915_drv.h"
#include "intel_context_types.h"
#include "intel_engine_types.h"
+#include "intel_gt_pm.h"
#include "intel_ring_types.h"
#include "intel_timeline_types.h"
#include "i915_trace.h"
@@ -207,8 +208,11 @@ void intel_context_exit_engine(struct intel_context *ce);
static inline void intel_context_enter(struct intel_context *ce)
{
lockdep_assert_held(&ce->timeline->mutex);
- if (!ce->active_count++)
- ce->ops->enter(ce);
+ if (ce->active_count++)
+ return;
+
+ ce->ops->enter(ce);
+ intel_gt_pm_get(ce->vm->gt);
}
static inline void intel_context_mark_active(struct intel_context *ce)
@@ -222,8 +226,11 @@ static inline void intel_context_exit(struct intel_context *ce)
{
lockdep_assert_held(&ce->timeline->mutex);
GEM_BUG_ON(!ce->active_count);
- if (!--ce->active_count)
- ce->ops->exit(ce);
+ if (--ce->active_count)
+ return;
+
+ intel_gt_pm_put_async(ce->vm->gt);
+ ce->ops->exit(ce);
shouldn't these two be swapped?
maybe I wasn't clear here... shouldn't it be
I missed this one.
ce->ops->exit(ce);
intel_gt_pm_put_async(ce->vm->gt);
Don't we need to hold the pm until exiting?
I think it doesn't matter. The problematic edge case this is fixing is
when ce->engine->gt is different from ce->vm->gt but at this point if it
is safe to release one it must be safe to release the other too.
Regards,
Tvrtko
}
static inline struct intel_context *intel_context_get(struct intel_context *ce)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_pm.c b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
index e971b153fda976..ee531a5c142c77 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_pm.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_pm.c
@@ -114,6 +114,15 @@ __queue_and_release_pm(struct i915_request *rq,
ENGINE_TRACE(engine, "parking\n");
+ /*
+ * Open coded one half of intel_context_enter, which we have to omit
+ * here (see the large comment below) and because the other part must
+ * not be called due constructing directly with __i915_request_create
+ * which increments active count via intel_context_mark_active.
+ */
+ GEM_BUG_ON(rq->context->active_count != 1);
+ __intel_gt_pm_get(engine->gt);
where is it's brother "put"?
It's in request retire via intel_context_exit. Ie. request construction is
special here, while retirement is standard.
Thank you!
Andi
