tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * Copyright 2015 Advanced Micro Devices, Inc.
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 shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 *
22 *
23 */
24#include <linux/kthread.h>
25#include <linux/wait.h>
26#include <linux/sched.h>
27#include <drm/drmP.h>
28#include "gpu_scheduler.h"
29
30static struct kmem_cache *sched_fence_slab;
31
32int amd_sched_fence_slab_init(void)
33{
34 sched_fence_slab = kmem_cache_create(
35 "amd_sched_fence", sizeof(struct amd_sched_fence), 0,
36 SLAB_HWCACHE_ALIGN, NULL);
37 if (!sched_fence_slab)
38 return -ENOMEM;
39
40 return 0;
41}
42
43void amd_sched_fence_slab_fini(void)
44{
45 rcu_barrier();
46 kmem_cache_destroy(sched_fence_slab);
47}
48
49struct amd_sched_fence *amd_sched_fence_create(struct amd_sched_entity *entity,
50 void *owner)
51{
52 struct amd_sched_fence *fence = NULL;
53 unsigned seq;
54
55 fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL);
56 if (fence == NULL)
57 return NULL;
58
59 fence->owner = owner;
60 fence->sched = entity->sched;
61 spin_lock_init(&fence->lock);
62
63 seq = atomic_inc_return(&entity->fence_seq);
64 dma_fence_init(&fence->scheduled, &amd_sched_fence_ops_scheduled,
65 &fence->lock, entity->fence_context, seq);
66 dma_fence_init(&fence->finished, &amd_sched_fence_ops_finished,
67 &fence->lock, entity->fence_context + 1, seq);
68
69 return fence;
70}
71
72void amd_sched_fence_scheduled(struct amd_sched_fence *fence)
73{
74 int ret = dma_fence_signal(&fence->scheduled);
75
76 if (!ret)
77 DMA_FENCE_TRACE(&fence->scheduled,
78 "signaled from irq context\n");
79 else
80 DMA_FENCE_TRACE(&fence->scheduled,
81 "was already signaled\n");
82}
83
84void amd_sched_fence_finished(struct amd_sched_fence *fence)
85{
86 int ret = dma_fence_signal(&fence->finished);
87
88 if (!ret)
89 DMA_FENCE_TRACE(&fence->finished,
90 "signaled from irq context\n");
91 else
92 DMA_FENCE_TRACE(&fence->finished,
93 "was already signaled\n");
94}
95
96static const char *amd_sched_fence_get_driver_name(struct dma_fence *fence)
97{
98 return "amd_sched";
99}
100
101static const char *amd_sched_fence_get_timeline_name(struct dma_fence *f)
102{
103 struct amd_sched_fence *fence = to_amd_sched_fence(f);
104 return (const char *)fence->sched->name;
105}
106
107static bool amd_sched_fence_enable_signaling(struct dma_fence *f)
108{
109 return true;
110}
111
112/**
113 * amd_sched_fence_free - free up the fence memory
114 *
115 * @rcu: RCU callback head
116 *
117 * Free up the fence memory after the RCU grace period.
118 */
119static void amd_sched_fence_free(struct rcu_head *rcu)
120{
121 struct dma_fence *f = container_of(rcu, struct dma_fence, rcu);
122 struct amd_sched_fence *fence = to_amd_sched_fence(f);
123
124 dma_fence_put(fence->parent);
125 kmem_cache_free(sched_fence_slab, fence);
126}
127
128/**
129 * amd_sched_fence_release_scheduled - callback that fence can be freed
130 *
131 * @fence: fence
132 *
133 * This function is called when the reference count becomes zero.
134 * It just RCU schedules freeing up the fence.
135 */
136static void amd_sched_fence_release_scheduled(struct dma_fence *f)
137{
138 struct amd_sched_fence *fence = to_amd_sched_fence(f);
139
140 call_rcu(&fence->finished.rcu, amd_sched_fence_free);
141}
142
143/**
144 * amd_sched_fence_release_finished - drop extra reference
145 *
146 * @f: fence
147 *
148 * Drop the extra reference from the scheduled fence to the base fence.
149 */
150static void amd_sched_fence_release_finished(struct dma_fence *f)
151{
152 struct amd_sched_fence *fence = to_amd_sched_fence(f);
153
154 dma_fence_put(&fence->scheduled);
155}
156
157const struct dma_fence_ops amd_sched_fence_ops_scheduled = {
158 .get_driver_name = amd_sched_fence_get_driver_name,
159 .get_timeline_name = amd_sched_fence_get_timeline_name,
160 .enable_signaling = amd_sched_fence_enable_signaling,
161 .signaled = NULL,
162 .wait = dma_fence_default_wait,
163 .release = amd_sched_fence_release_scheduled,
164};
165
166const struct dma_fence_ops amd_sched_fence_ops_finished = {
167 .get_driver_name = amd_sched_fence_get_driver_name,
168 .get_timeline_name = amd_sched_fence_get_timeline_name,
169 .enable_signaling = amd_sched_fence_enable_signaling,
170 .signaled = NULL,
171 .wait = dma_fence_default_wait,
172 .release = amd_sched_fence_release_finished,
173};