Commit 2d0fb251 authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915: Serialise with remote retirement 



Since retirement may be running in a worker on another CPU, it may be
skipped in the local intel_gt_wait_for_idle(). To ensure the state is
consistent for our sanity checks upon load, serialise with the remote
retirer by waiting on the timeline->mutex.

Outside of this use case, e.g. on suspend or module unload, we expect the
slack to be picked up by intel_gt_pm_wait_for_idle() and so prefer to
put the special case serialisation with retirement in its single user,
for now at least.

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: default avatarTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191121071044.97798-2-chris@chris-wilson.co.uk
parent 689122dc

drivers/gpu/drm/i915/i915_gem.c

+23 −3
Original line number Diff line number Diff line
@@ -45,6 +45,7 @@ 
#include "gem/i915_gem_context.h"

#include "gem/i915_gem_ioctls.h"

#include "gem/i915_gem_pm.h"

#include "gt/intel_context.h"

#include "gt/intel_engine_user.h"

#include "gt/intel_gt.h"

#include "gt/intel_gt_pm.h"
@@ -1041,6 +1042,18 @@ out: 
	return err;

}



static int __intel_context_flush_retire(struct intel_context *ce)

{

	struct intel_timeline *tl;



	tl = intel_context_timeline_lock(ce);

	if (IS_ERR(tl))

		return PTR_ERR(tl);



	intel_context_timeline_unlock(tl);

	return 0;

}



static int __intel_engines_record_defaults(struct intel_gt *gt)

{

	struct i915_request *requests[I915_NUM_ENGINES] = {};
@@ -1109,13 +1122,20 @@ err_rq: 
		if (!rq)

			continue;



		/* We want to be able to unbind the state from the GGTT */

		GEM_BUG_ON(intel_context_is_pinned(rq->hw_context));



		GEM_BUG_ON(!test_bit(CONTEXT_ALLOC_BIT,

				     &rq->hw_context->flags));

		state = rq->hw_context->state;

		if (!state)

			continue;



		/* Serialise with retirement on another CPU */

		err = __intel_context_flush_retire(rq->hw_context);

		if (err)

			goto out;



		/* We want to be able to unbind the state from the GGTT */

		GEM_BUG_ON(intel_context_is_pinned(rq->hw_context));



		/*

		 * As we will hold a reference to the logical state, it will

		 * not be torn down with the context, and importantly the

CRA Git | Maintained and supported by SUSTech CRA and CCSE