Line data Source code
1 : /*
2 : * Copyright (C) 2013 Red Hat
3 : *
4 : * Permission is hereby granted, free of charge, to any person obtaining a
5 : * copy of this software and associated documentation files (the "Software"),
6 : * to deal in the Software without restriction, including without limitation
7 : * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 : * and/or sell copies of the Software, and to permit persons to whom the
9 : * Software is furnished to do so, subject to the following conditions:
10 : *
11 : * The above copyright notice and this permission notice (including the next
12 : * paragraph) shall be included in all copies or substantial portions of the
13 : * Software.
14 : *
15 : * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 : * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 : * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 : * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 : * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 : * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 : * SOFTWARE.
22 : */
23 :
24 : #include <linux/slab.h>
25 :
26 : #include <drm/drm_flip_work.h>
27 : #include <drm/drm_print.h>
28 : #include <drm/drm_util.h>
29 :
30 : /**
31 : * drm_flip_work_allocate_task - allocate a flip-work task
32 : * @data: data associated to the task
33 : * @flags: allocator flags
34 : *
35 : * Allocate a drm_flip_task object and attach private data to it.
36 : */
37 0 : struct drm_flip_task *drm_flip_work_allocate_task(void *data, gfp_t flags)
38 : {
39 : struct drm_flip_task *task;
40 :
41 0 : task = kzalloc(sizeof(*task), flags);
42 0 : if (task)
43 0 : task->data = data;
44 :
45 0 : return task;
46 : }
47 : EXPORT_SYMBOL(drm_flip_work_allocate_task);
48 :
49 : /**
50 : * drm_flip_work_queue_task - queue a specific task
51 : * @work: the flip-work
52 : * @task: the task to handle
53 : *
54 : * Queues task, that will later be run (passed back to drm_flip_func_t
55 : * func) on a work queue after drm_flip_work_commit() is called.
56 : */
57 0 : void drm_flip_work_queue_task(struct drm_flip_work *work,
58 : struct drm_flip_task *task)
59 : {
60 : unsigned long flags;
61 :
62 0 : spin_lock_irqsave(&work->lock, flags);
63 0 : list_add_tail(&task->node, &work->queued);
64 0 : spin_unlock_irqrestore(&work->lock, flags);
65 0 : }
66 : EXPORT_SYMBOL(drm_flip_work_queue_task);
67 :
68 : /**
69 : * drm_flip_work_queue - queue work
70 : * @work: the flip-work
71 : * @val: the value to queue
72 : *
73 : * Queues work, that will later be run (passed back to drm_flip_func_t
74 : * func) on a work queue after drm_flip_work_commit() is called.
75 : */
76 0 : void drm_flip_work_queue(struct drm_flip_work *work, void *val)
77 : {
78 : struct drm_flip_task *task;
79 :
80 0 : task = drm_flip_work_allocate_task(val,
81 0 : drm_can_sleep() ? GFP_KERNEL : GFP_ATOMIC);
82 0 : if (task) {
83 0 : drm_flip_work_queue_task(work, task);
84 : } else {
85 0 : DRM_ERROR("%s could not allocate task!\n", work->name);
86 0 : work->func(work, val);
87 : }
88 0 : }
89 : EXPORT_SYMBOL(drm_flip_work_queue);
90 :
91 : /**
92 : * drm_flip_work_commit - commit queued work
93 : * @work: the flip-work
94 : * @wq: the work-queue to run the queued work on
95 : *
96 : * Trigger work previously queued by drm_flip_work_queue() to run
97 : * on a workqueue. The typical usage would be to queue work (via
98 : * drm_flip_work_queue()) at any point (from vblank irq and/or
99 : * prior), and then from vblank irq commit the queued work.
100 : */
101 0 : void drm_flip_work_commit(struct drm_flip_work *work,
102 : struct workqueue_struct *wq)
103 : {
104 : unsigned long flags;
105 :
106 0 : spin_lock_irqsave(&work->lock, flags);
107 0 : list_splice_tail(&work->queued, &work->commited);
108 0 : INIT_LIST_HEAD(&work->queued);
109 0 : spin_unlock_irqrestore(&work->lock, flags);
110 0 : queue_work(wq, &work->worker);
111 0 : }
112 : EXPORT_SYMBOL(drm_flip_work_commit);
113 :
114 0 : static void flip_worker(struct work_struct *w)
115 : {
116 0 : struct drm_flip_work *work = container_of(w, struct drm_flip_work, worker);
117 : struct list_head tasks;
118 : unsigned long flags;
119 :
120 : while (1) {
121 : struct drm_flip_task *task, *tmp;
122 :
123 0 : INIT_LIST_HEAD(&tasks);
124 0 : spin_lock_irqsave(&work->lock, flags);
125 0 : list_splice_tail(&work->commited, &tasks);
126 0 : INIT_LIST_HEAD(&work->commited);
127 0 : spin_unlock_irqrestore(&work->lock, flags);
128 :
129 0 : if (list_empty(&tasks))
130 : break;
131 :
132 0 : list_for_each_entry_safe(task, tmp, &tasks, node) {
133 0 : work->func(work, task->data);
134 0 : kfree(task);
135 : }
136 : }
137 0 : }
138 :
139 : /**
140 : * drm_flip_work_init - initialize flip-work
141 : * @work: the flip-work to initialize
142 : * @name: debug name
143 : * @func: the callback work function
144 : *
145 : * Initializes/allocates resources for the flip-work
146 : */
147 0 : void drm_flip_work_init(struct drm_flip_work *work,
148 : const char *name, drm_flip_func_t func)
149 : {
150 0 : work->name = name;
151 0 : INIT_LIST_HEAD(&work->queued);
152 0 : INIT_LIST_HEAD(&work->commited);
153 0 : spin_lock_init(&work->lock);
154 0 : work->func = func;
155 :
156 0 : INIT_WORK(&work->worker, flip_worker);
157 0 : }
158 : EXPORT_SYMBOL(drm_flip_work_init);
159 :
160 : /**
161 : * drm_flip_work_cleanup - cleans up flip-work
162 : * @work: the flip-work to cleanup
163 : *
164 : * Destroy resources allocated for the flip-work
165 : */
166 0 : void drm_flip_work_cleanup(struct drm_flip_work *work)
167 : {
168 0 : WARN_ON(!list_empty(&work->queued) || !list_empty(&work->commited));
169 0 : }
170 : EXPORT_SYMBOL(drm_flip_work_cleanup);
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