Commit 1424ba81 authored by Matthew Brost's avatar Matthew Brost Committed by John Harrison
Browse files

drm/i915/guc: Proper xarray usage for contexts_lookup 



Lock the xarray and take ref to the context if needed.

v2:
 (Checkpatch)
  - Add new line after declaration
 (Daniel Vetter)
  - Correct put / get accounting in xa_for_loops
v3:
 (Checkpatch)
  - Extra new line

Reviewed-by: default avatarDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Signed-off-by: default avatarJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210909164744.31249-19-matthew.brost@intel.com
parent 0f797650

drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c

+87 −15
Original line number Diff line number Diff line
@@ -608,8 +608,18 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc) 
	unsigned long index, flags;

	bool pending_disable, pending_enable, deregister, destroyed, banned;



	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		spin_lock_irqsave(&ce->guc_state.lock, flags);

		/*

		 * Corner case where the ref count on the object is zero but and

		 * deregister G2H was lost. In this case we don't touch the ref

		 * count and finish the destroy of the context.

		 */

		bool do_put = kref_get_unless_zero(&ce->ref);



		xa_unlock(&guc->context_lookup);



		spin_lock(&ce->guc_state.lock);



		/*

		 * Once we are at this point submission_disabled() is guaranteed
@@ -625,7 +635,9 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc) 
		banned = context_banned(ce);

		init_sched_state(ce);



		spin_unlock_irqrestore(&ce->guc_state.lock, flags);

		spin_unlock(&ce->guc_state.lock);



		GEM_BUG_ON(!do_put && !destroyed);



		if (pending_enable || destroyed || deregister) {

			decr_outstanding_submission_g2h(guc);
@@ -648,13 +660,19 @@ static void scrub_guc_desc_for_outstanding_g2h(struct intel_guc *guc) 
			}

			intel_context_sched_disable_unpin(ce);

			decr_outstanding_submission_g2h(guc);

			spin_lock_irqsave(&ce->guc_state.lock, flags);



			spin_lock(&ce->guc_state.lock);

			guc_blocked_fence_complete(ce);

			spin_unlock_irqrestore(&ce->guc_state.lock, flags);

			spin_unlock(&ce->guc_state.lock);



			intel_context_put(ce);

		}



		if (do_put)

			intel_context_put(ce);

		xa_lock(&guc->context_lookup);

	}

	xa_unlock_irqrestore(&guc->context_lookup, flags);

}



static inline bool
@@ -890,16 +908,29 @@ void intel_guc_submission_reset(struct intel_guc *guc, bool stalled) 
{

	struct intel_context *ce;

	unsigned long index;

	unsigned long flags;



	if (unlikely(!guc_submission_initialized(guc))) {

		/* Reset called during driver load? GuC not yet initialised! */

		return;

	}



	xa_for_each(&guc->context_lookup, index, ce)

	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		if (!kref_get_unless_zero(&ce->ref))

			continue;



		xa_unlock(&guc->context_lookup);



		if (intel_context_is_pinned(ce))

			__guc_reset_context(ce, stalled);



		intel_context_put(ce);



		xa_lock(&guc->context_lookup);

	}

	xa_unlock_irqrestore(&guc->context_lookup, flags);



	/* GuC is blown away, drop all references to contexts */

	xa_destroy(&guc->context_lookup);

}
@@ -974,11 +1005,24 @@ void intel_guc_submission_cancel_requests(struct intel_guc *guc) 
{

	struct intel_context *ce;

	unsigned long index;

	unsigned long flags;



	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		if (!kref_get_unless_zero(&ce->ref))

			continue;



		xa_unlock(&guc->context_lookup);



	xa_for_each(&guc->context_lookup, index, ce)

		if (intel_context_is_pinned(ce))

			guc_cancel_context_requests(ce);



		intel_context_put(ce);



		xa_lock(&guc->context_lookup);

	}

	xa_unlock_irqrestore(&guc->context_lookup, flags);



	guc_cancel_sched_engine_requests(guc->sched_engine);



	/* GuC is blown away, drop all references to contexts */
@@ -2866,21 +2910,28 @@ void intel_guc_find_hung_context(struct intel_engine_cs *engine) 
	struct intel_context *ce;

	struct i915_request *rq;

	unsigned long index;

	unsigned long flags;



	/* Reset called during driver load? GuC not yet initialised! */

	if (unlikely(!guc_submission_initialized(guc)))

		return;



	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		if (!intel_context_is_pinned(ce))

		if (!kref_get_unless_zero(&ce->ref))

			continue;



		xa_unlock(&guc->context_lookup);



		if (!intel_context_is_pinned(ce))

			goto next;



		if (intel_engine_is_virtual(ce->engine)) {

			if (!(ce->engine->mask & engine->mask))

				continue;

				goto next;

		} else {

			if (ce->engine != engine)

				continue;

				goto next;

		}



		list_for_each_entry(rq, &ce->guc_active.requests, sched.link) {
@@ -2890,9 +2941,16 @@ void intel_guc_find_hung_context(struct intel_engine_cs *engine) 
			intel_engine_set_hung_context(engine, ce);



			/* Can only cope with one hang at a time... */

			return;

			intel_context_put(ce);

			xa_lock(&guc->context_lookup);

			goto done;

		}

next:

		intel_context_put(ce);

		xa_lock(&guc->context_lookup);

	}

done:

	xa_unlock_irqrestore(&guc->context_lookup, flags);

}



void intel_guc_dump_active_requests(struct intel_engine_cs *engine,
@@ -2908,23 +2966,34 @@ void intel_guc_dump_active_requests(struct intel_engine_cs *engine, 
	if (unlikely(!guc_submission_initialized(guc)))

		return;



	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		if (!intel_context_is_pinned(ce))

		if (!kref_get_unless_zero(&ce->ref))

			continue;



		xa_unlock(&guc->context_lookup);



		if (!intel_context_is_pinned(ce))

			goto next;



		if (intel_engine_is_virtual(ce->engine)) {

			if (!(ce->engine->mask & engine->mask))

				continue;

				goto next;

		} else {

			if (ce->engine != engine)

				continue;

				goto next;

		}



		spin_lock_irqsave(&ce->guc_active.lock, flags);

		spin_lock(&ce->guc_active.lock);

		intel_engine_dump_active_requests(&ce->guc_active.requests,

						  hung_rq, m);

		spin_unlock_irqrestore(&ce->guc_active.lock, flags);

		spin_unlock(&ce->guc_active.lock);



next:

		intel_context_put(ce);

		xa_lock(&guc->context_lookup);

	}

	xa_unlock_irqrestore(&guc->context_lookup, flags);

}



void intel_guc_submission_print_info(struct intel_guc *guc,
@@ -2978,7 +3047,9 @@ void intel_guc_submission_print_context_info(struct intel_guc *guc, 
{

	struct intel_context *ce;

	unsigned long index;

	unsigned long flags;



	xa_lock_irqsave(&guc->context_lookup, flags);

	xa_for_each(&guc->context_lookup, index, ce) {

		drm_printf(p, "GuC lrc descriptor %u:\n", ce->guc_id);

		drm_printf(p, "\tHW Context Desc: 0x%08x\n", ce->lrc.lrca);
@@ -2997,6 +3068,7 @@ void intel_guc_submission_print_context_info(struct intel_guc *guc, 


		guc_log_context_priority(p, ce);

	}

	xa_unlock_irqrestore(&guc->context_lookup, flags);

}



static struct intel_context *