Commit 62eaf0ae authored by Matthew Brost's avatar Matthew Brost Committed by John Harrison
Browse files

drm/i915/guc: Support request cancellation 



This adds GuC backend support for i915_request_cancel(), which in turn
makes CONFIG_DRM_I915_REQUEST_TIMEOUT work.

This implementation makes use of fence while there are likely simplier
options. A fence was chosen because of another feature coming soon
which requires a user to block on a context until scheduling is
disabled. In that case we return the fence to the user and the user can
wait on that fence.

v2:
 (Daniele)
  - A comment about locking the blocked incr / decr
  - A comments about the use of the fence
  - Update commit message explaining why fence
  - Delete redundant check blocked count in unblock function
  - Ring buffer implementation
  - Comment about blocked in submission path
  - Shorter rpm path
v3:
 (Checkpatch)
  - Fix typos in commit message
 (Daniel)
  - Rework to simplier locking structure in guc_context_block / unblock

Signed-off-by: default avatarMatthew Brost <matthew.brost@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: default avatarDaniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: default avatarJohn Harrison <John.C.Harrison@Intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210727002348.97202-26-matthew.brost@intel.com
parent ae8ac10d

drivers/gpu/drm/i915/gt/intel_context.c

+13 −0
Original line number Diff line number Diff line
@@ -366,6 +366,12 @@ static int __intel_context_active(struct i915_active *active) 
	return 0;

}



static int sw_fence_dummy_notify(struct i915_sw_fence *sf,

				 enum i915_sw_fence_notify state)

{

	return NOTIFY_DONE;

}



void

intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine)

{
@@ -399,6 +405,13 @@ intel_context_init(struct intel_context *ce, struct intel_engine_cs *engine) 
	ce->guc_id = GUC_INVALID_LRC_ID;

	INIT_LIST_HEAD(&ce->guc_id_link);



	/*

	 * Initialize fence to be complete as this is expected to be complete

	 * unless there is a pending schedule disable outstanding.

	 */

	i915_sw_fence_init(&ce->guc_blocked, sw_fence_dummy_notify);

	i915_sw_fence_commit(&ce->guc_blocked);



	i915_active_init(&ce->active,

			 __intel_context_active, __intel_context_retire, 0);

}

drivers/gpu/drm/i915/gt/intel_context.h

+7 −0
Original line number Diff line number Diff line
@@ -70,6 +70,13 @@ intel_context_is_pinned(struct intel_context *ce) 
	return atomic_read(&ce->pin_count);

}



static inline void intel_context_cancel_request(struct intel_context *ce,

						struct i915_request *rq)

{

	GEM_BUG_ON(!ce->ops->cancel_request);

	return ce->ops->cancel_request(ce, rq);

}



/**

 * intel_context_unlock_pinned - Releases the earlier locking of 'pinned' status

 * @ce - the context

drivers/gpu/drm/i915/gt/intel_context_types.h

+8 −1
Original line number Diff line number Diff line
@@ -13,6 +13,7 @@ 
#include <linux/types.h>



#include "i915_active_types.h"

#include "i915_sw_fence.h"

#include "i915_utils.h"

#include "intel_engine_types.h"

#include "intel_sseu.h"
@@ -42,6 +43,9 @@ struct intel_context_ops { 
	void (*unpin)(struct intel_context *ce);

	void (*post_unpin)(struct intel_context *ce);



	void (*cancel_request)(struct intel_context *ce,

			       struct i915_request *rq);



	void (*enter)(struct intel_context *ce);

	void (*exit)(struct intel_context *ce);
@@ -156,7 +160,7 @@ struct intel_context { 
		 * sched_state: scheduling state of this context using GuC

		 * submission

		 */

		u8 sched_state;

		u16 sched_state;

		/*

		 * fences: maintains of list of requests that have a submit

		 * fence related to GuC submission
@@ -184,6 +188,9 @@ struct intel_context { 
	 * GuC ID link - in list when unpinned but guc_id still valid in GuC

	 */

	struct list_head guc_id_link;



	/* GuC context blocked fence */

	struct i915_sw_fence guc_blocked;

};



#endif /* __INTEL_CONTEXT_TYPES__ */

drivers/gpu/drm/i915/gt/intel_execlists_submission.c

+18 −0
Original line number Diff line number Diff line
@@ -114,6 +114,7 @@ 
#include "gen8_engine_cs.h"

#include "intel_breadcrumbs.h"

#include "intel_context.h"

#include "intel_engine_heartbeat.h"

#include "intel_engine_pm.h"

#include "intel_engine_stats.h"

#include "intel_execlists_submission.h"
@@ -2587,11 +2588,26 @@ static int execlists_context_alloc(struct intel_context *ce) 
	return lrc_alloc(ce, ce->engine);

}



static void execlists_context_cancel_request(struct intel_context *ce,

					     struct i915_request *rq)

{

	struct intel_engine_cs *engine = NULL;



	i915_request_active_engine(rq, &engine);



	if (engine && intel_engine_pulse(engine))

		intel_gt_handle_error(engine->gt, engine->mask, 0,

				      "request cancellation by %s",

				      current->comm);

}



static const struct intel_context_ops execlists_context_ops = {

	.flags = COPS_HAS_INFLIGHT,



	.alloc = execlists_context_alloc,



	.cancel_request = execlists_context_cancel_request,



	.pre_pin = execlists_context_pre_pin,

	.pin = execlists_context_pin,

	.unpin = lrc_unpin,
@@ -3608,6 +3624,8 @@ static const struct intel_context_ops virtual_context_ops = { 


	.alloc = virtual_context_alloc,



	.cancel_request = execlists_context_cancel_request,



	.pre_pin = virtual_context_pre_pin,

	.pin = virtual_context_pin,

	.unpin = lrc_unpin,

drivers/gpu/drm/i915/gt/intel_ring_submission.c

+16 −0
Original line number Diff line number Diff line
@@ -16,6 +16,7 @@ 
#include "intel_reset.h"

#include "intel_ring.h"

#include "shmem_utils.h"

#include "intel_engine_heartbeat.h"



/* Rough estimate of the typical request size, performing a flush,

 * set-context and then emitting the batch.
@@ -604,9 +605,24 @@ static void ring_context_ban(struct intel_context *ce, 
		}

}



static void ring_context_cancel_request(struct intel_context *ce,

					struct i915_request *rq)

{

	struct intel_engine_cs *engine = NULL;



	i915_request_active_engine(rq, &engine);



	if (engine && intel_engine_pulse(engine))

		intel_gt_handle_error(engine->gt, engine->mask, 0,

				      "request cancellation by %s",

				      current->comm);

}



static const struct intel_context_ops ring_context_ops = {

	.alloc = ring_context_alloc,



	.cancel_request = ring_context_cancel_request,



	.ban = ring_context_ban,



	.pre_pin = ring_context_pre_pin,