summaryrefslogtreecommitdiffstats
path: root/drivers/gpu/drm/drm_flip_work.c
blob: 43d9b950ef9fd03bb0f7eb267a0c46a01e6688c7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
/*
 * Copyright (C) 2013 Red Hat
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "drmP.h"
#include "drm_flip_work.h"

/**
 * drm_flip_work_allocate_task - allocate a flip-work task
 * @data: data associated to the task
 * @flags: allocator flags
 *
 * Allocate a drm_flip_task object and attach private data to it.
 */
struct drm_flip_task *drm_flip_work_allocate_task(void *data, gfp_t flags)
{
	struct drm_flip_task *task;

	task = kzalloc(sizeof(*task), flags);
	if (task)
		task->data = data;

	return task;
}
EXPORT_SYMBOL(drm_flip_work_allocate_task);

/**
 * drm_flip_work_queue_task - queue a specific task
 * @work: the flip-work
 * @task: the task to handle
 *
 * Queues task, that will later be run (passed back to drm_flip_func_t
 * func) on a work queue after drm_flip_work_commit() is called.
 */
void drm_flip_work_queue_task(struct drm_flip_work *work,
			      struct drm_flip_task *task)
{
	unsigned long flags;

	spin_lock_irqsave(&work->lock, flags);
	list_add_tail(&task->node, &work->queued);
	spin_unlock_irqrestore(&work->lock, flags);
}
EXPORT_SYMBOL(drm_flip_work_queue_task);

/**
 * drm_flip_work_queue - queue work
 * @work: the flip-work
 * @val: the value to queue
 *
 * Queues work, that will later be run (passed back to drm_flip_func_t
 * func) on a work queue after drm_flip_work_commit() is called.
 */
void drm_flip_work_queue(struct drm_flip_work *work, void *val)
{
	struct drm_flip_task *task;

	task = drm_flip_work_allocate_task(val,
				drm_can_sleep() ? GFP_KERNEL : GFP_ATOMIC);
	if (task) {
		drm_flip_work_queue_task(work, task);
	} else {
		DRM_ERROR("%s could not allocate task!\n", work->name);
		work->func(work, val);
	}
}
EXPORT_SYMBOL(drm_flip_work_queue);

/**
 * drm_flip_work_commit - commit queued work
 * @work: the flip-work
 * @wq: the work-queue to run the queued work on
 *
 * Trigger work previously queued by drm_flip_work_queue() to run
 * on a workqueue.  The typical usage would be to queue work (via
 * drm_flip_work_queue()) at any point (from vblank irq and/or
 * prior), and then from vblank irq commit the queued work.
 */
void drm_flip_work_commit(struct drm_flip_work *work,
		struct workqueue_struct *wq)
{
	unsigned long flags;

	spin_lock_irqsave(&work->lock, flags);
	list_splice_tail(&work->queued, &work->commited);
	INIT_LIST_HEAD(&work->queued);
	spin_unlock_irqrestore(&work->lock, flags);
	queue_work(wq, &work->worker);
}
EXPORT_SYMBOL(drm_flip_work_commit);

static void flip_worker(struct work_struct *w)
{
	struct drm_flip_work *work = container_of(w, struct drm_flip_work, worker);
	struct list_head tasks;
	unsigned long flags;

	while (1) {
		struct drm_flip_task *task, *tmp;

		INIT_LIST_HEAD(&tasks);
		spin_lock_irqsave(&work->lock, flags);
		list_splice_tail(&work->commited, &tasks);
		INIT_LIST_HEAD(&work->commited);
		spin_unlock_irqrestore(&work->lock, flags);

		if (list_empty(&tasks))
			break;

		list_for_each_entry_safe(task, tmp, &tasks, node) {
			work->func(work, task->data);
			kfree(task);
		}
	}
}

/**
 * drm_flip_work_init - initialize flip-work
 * @work: the flip-work to initialize
 * @name: debug name
 * @func: the callback work function
 *
 * Initializes/allocates resources for the flip-work
 */
void drm_flip_work_init(struct drm_flip_work *work,
		const char *name, drm_flip_func_t func)
{
	work->name = name;
	INIT_LIST_HEAD(&work->queued);
	INIT_LIST_HEAD(&work->commited);
	spin_lock_init(&work->lock);
	work->func = func;

	INIT_WORK(&work->worker, flip_worker);
}
EXPORT_SYMBOL(drm_flip_work_init);

/**
 * drm_flip_work_cleanup - cleans up flip-work
 * @work: the flip-work to cleanup
 *
 * Destroy resources allocated for the flip-work
 */
void drm_flip_work_cleanup(struct drm_flip_work *work)
{
	WARN_ON(!list_empty(&work->queued) || !list_empty(&work->commited));
}
EXPORT_SYMBOL(drm_flip_work_cleanup);