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 | struct drm_flip_task *drm_flip_work_allocate_task(void *data, gfp_t flags) |
38 | { |
39 | struct drm_flip_task *task; |
40 | |
41 | task = kzalloc(size: sizeof(*task), flags); |
42 | if (task) |
43 | task->data = data; |
44 | |
45 | 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 | void drm_flip_work_queue_task(struct drm_flip_work *work, |
58 | struct drm_flip_task *task) |
59 | { |
60 | unsigned long flags; |
61 | |
62 | spin_lock_irqsave(&work->lock, flags); |
63 | list_add_tail(new: &task->node, head: &work->queued); |
64 | spin_unlock_irqrestore(lock: &work->lock, flags); |
65 | } |
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 | void drm_flip_work_queue(struct drm_flip_work *work, void *val) |
77 | { |
78 | struct drm_flip_task *task; |
79 | |
80 | task = drm_flip_work_allocate_task(val, |
81 | drm_can_sleep() ? GFP_KERNEL : GFP_ATOMIC); |
82 | if (task) { |
83 | drm_flip_work_queue_task(work, task); |
84 | } else { |
85 | DRM_ERROR("%s could not allocate task!\n" , work->name); |
86 | work->func(work, val); |
87 | } |
88 | } |
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 | void drm_flip_work_commit(struct drm_flip_work *work, |
102 | struct workqueue_struct *wq) |
103 | { |
104 | unsigned long flags; |
105 | |
106 | spin_lock_irqsave(&work->lock, flags); |
107 | list_splice_tail(list: &work->queued, head: &work->commited); |
108 | INIT_LIST_HEAD(list: &work->queued); |
109 | spin_unlock_irqrestore(lock: &work->lock, flags); |
110 | queue_work(wq, work: &work->worker); |
111 | } |
112 | EXPORT_SYMBOL(drm_flip_work_commit); |
113 | |
114 | static void flip_worker(struct work_struct *w) |
115 | { |
116 | 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 | INIT_LIST_HEAD(list: &tasks); |
124 | spin_lock_irqsave(&work->lock, flags); |
125 | list_splice_tail(list: &work->commited, head: &tasks); |
126 | INIT_LIST_HEAD(list: &work->commited); |
127 | spin_unlock_irqrestore(lock: &work->lock, flags); |
128 | |
129 | if (list_empty(head: &tasks)) |
130 | break; |
131 | |
132 | list_for_each_entry_safe(task, tmp, &tasks, node) { |
133 | work->func(work, task->data); |
134 | kfree(objp: task); |
135 | } |
136 | } |
137 | } |
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 | void drm_flip_work_init(struct drm_flip_work *work, |
148 | const char *name, drm_flip_func_t func) |
149 | { |
150 | work->name = name; |
151 | INIT_LIST_HEAD(list: &work->queued); |
152 | INIT_LIST_HEAD(list: &work->commited); |
153 | spin_lock_init(&work->lock); |
154 | work->func = func; |
155 | |
156 | INIT_WORK(&work->worker, flip_worker); |
157 | } |
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 | void drm_flip_work_cleanup(struct drm_flip_work *work) |
167 | { |
168 | WARN_ON(!list_empty(&work->queued) || !list_empty(&work->commited)); |
169 | } |
170 | EXPORT_SYMBOL(drm_flip_work_cleanup); |
171 | |