[linux-2.6-block.git] / drivers / gpu / drm / i915 / i915_scheduler_types.h

/*
 * SPDX-License-Identifier: MIT
 *
 * Copyright © 2018 Intel Corporation
 */

#ifndef _I915_SCHEDULER_TYPES_H_
#define _I915_SCHEDULER_TYPES_H_

#include <linux/list.h>

#include "gt/intel_engine_types.h"
#include "i915_priolist_types.h"

struct drm_i915_private;
struct i915_request;
struct intel_engine_cs;

struct i915_sched_attr {
	/**
	 * @priority: execution and service priority
	 *
	 * All clients are equal, but some are more equal than others!
	 *
	 * Requests from a context with a greater (more positive) value of
	 * @priority will be executed before those with a lower @priority
	 * value, forming a simple QoS.
	 *
	 * The &drm_i915_private.kernel_context is assigned the lowest priority.
	 */
	int priority;
};

/*
 * "People assume that time is a strict progression of cause to effect, but
 * actually, from a nonlinear, non-subjective viewpoint, it's more like a big
 * ball of wibbly-wobbly, timey-wimey ... stuff." -The Doctor, 2015
 *
 * Requests exist in a complex web of interdependencies. Each request
 * has to wait for some other request to complete before it is ready to be run
 * (e.g. we have to wait until the pixels have been rendering into a texture
 * before we can copy from it). We track the readiness of a request in terms
 * of fences, but we also need to keep the dependency tree for the lifetime
 * of the request (beyond the life of an individual fence). We use the tree
 * at various points to reorder the requests whilst keeping the requests
 * in order with respect to their various dependencies.
 *
 * There is no active component to the "scheduler". As we know the dependency
 * DAG of each request, we are able to insert it into a sorted queue when it
 * is ready, and are able to reorder its portion of the graph to accommodate
 * dynamic priority changes.
 */
struct i915_sched_node {
	struct list_head signalers_list; /* those before us, we depend upon */
	struct list_head waiters_list; /* those after us, they depend upon us */
	struct list_head link;
	struct i915_sched_attr attr;
	unsigned int flags;
#define I915_SCHED_HAS_SEMAPHORE_CHAIN	BIT(0)
	intel_engine_mask_t semaphores;
};

struct i915_dependency {
	struct i915_sched_node *signaler;
	struct list_head signal_link;
	struct list_head wait_link;
	struct list_head dfs_link;
	unsigned long flags;
#define I915_DEPENDENCY_ALLOC		BIT(0)
#define I915_DEPENDENCY_EXTERNAL	BIT(1)
};

#endif /* _I915_SCHEDULER_TYPES_H_ */
Commit	Line	Data
3a891a62 CW	1	/*
	2	* SPDX-License-Identifier: MIT
	3	*
	4	* Copyright © 2018 Intel Corporation
	5	*/
	6
	7	#ifndef _I915_SCHEDULER_TYPES_H_
	8	#define _I915_SCHEDULER_TYPES_H_
	9
	10	#include <linux/list.h>
3a891a62	11
112ed2d3	12	#include "gt/intel_engine_types.h"
8b74594a	13	#include "i915_priolist_types.h"
3a891a62 CW	14
	15	struct drm_i915_private;
	16	struct i915_request;
	17	struct intel_engine_cs;
	18
3a891a62 CW	19	struct i915_sched_attr {
	20	/**
	21	* @priority: execution and service priority
	22	*
	23	* All clients are equal, but some are more equal than others!
	24	*
	25	* Requests from a context with a greater (more positive) value of
	26	* @priority will be executed before those with a lower @priority
	27	* value, forming a simple QoS.
	28	*
	29	* The &drm_i915_private.kernel_context is assigned the lowest priority.
	30	*/
	31	int priority;
	32	};
	33
	34	/*
	35	* "People assume that time is a strict progression of cause to effect, but
	36	* actually, from a nonlinear, non-subjective viewpoint, it's more like a big
	37	* ball of wibbly-wobbly, timey-wimey ... stuff." -The Doctor, 2015
	38	*
	39	* Requests exist in a complex web of interdependencies. Each request
	40	* has to wait for some other request to complete before it is ready to be run
	41	* (e.g. we have to wait until the pixels have been rendering into a texture
	42	* before we can copy from it). We track the readiness of a request in terms
	43	* of fences, but we also need to keep the dependency tree for the lifetime
	44	* of the request (beyond the life of an individual fence). We use the tree
	45	* at various points to reorder the requests whilst keeping the requests
	46	* in order with respect to their various dependencies.
	47	*
	48	* There is no active component to the "scheduler". As we know the dependency
	49	* DAG of each request, we are able to insert it into a sorted queue when it
	50	* is ready, and are able to reorder its portion of the graph to accommodate
	51	* dynamic priority changes.
	52	*/
	53	struct i915_sched_node {
	54	struct list_head signalers_list; /* those before us, we depend upon */
	55	struct list_head waiters_list; /* those after us, they depend upon us */
	56	struct list_head link;
	57	struct i915_sched_attr attr;
	58	unsigned int flags;
7881e605 CW	59	#define I915_SCHED_HAS_SEMAPHORE_CHAIN BIT(0)
7881e605 CW	60	intel_engine_mask_t semaphores;
3a891a62 CW	61	};
	62
	63	struct i915_dependency {
	64	struct i915_sched_node *signaler;
	65	struct list_head signal_link;
	66	struct list_head wait_link;
	67	struct list_head dfs_link;
	68	unsigned long flags;
6e7eb7a8 CW	69	#define I915_DEPENDENCY_ALLOC BIT(0)
6e7eb7a8 CW	70	#define I915_DEPENDENCY_EXTERNAL BIT(1)
3a891a62 CW	71	};
3a891a62 CW	72
3a891a62	73	#endif /* _I915_SCHEDULER_TYPES_H_ */