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/module.h> 26 #include <linux/sched.h> 27 #include <linux/slab.h> 28 #include <linux/wait.h> 29 30 #include <drm/gpu_scheduler.h> 31 32 #include <sys/pool.h> 33 34 static struct pool sched_fence_slab; 35 36 int __init drm_sched_fence_slab_init(void) 37 { 38 #ifdef __linux__ 39 sched_fence_slab = kmem_cache_create( 40 "drm_sched_fence", sizeof(struct drm_sched_fence), 0, 41 SLAB_HWCACHE_ALIGN, NULL); 42 if (!sched_fence_slab) 43 return -ENOMEM; 44 #else 45 pool_init(&sched_fence_slab, sizeof(struct drm_sched_fence), 46 CACHELINESIZE, IPL_TTY, 0, "drm_sched_fence", NULL); 47 #endif 48 49 return 0; 50 } 51 52 void __exit drm_sched_fence_slab_fini(void) 53 { 54 rcu_barrier(); 55 #ifdef __linux__ 56 kmem_cache_destroy(sched_fence_slab); 57 #else 58 pool_destroy(&sched_fence_slab); 59 #endif 60 } 61 62 void drm_sched_fence_scheduled(struct drm_sched_fence *fence) 63 { 64 dma_fence_signal(&fence->scheduled); 65 } 66 67 void drm_sched_fence_finished(struct drm_sched_fence *fence) 68 { 69 dma_fence_signal(&fence->finished); 70 } 71 72 static const char *drm_sched_fence_get_driver_name(struct dma_fence *fence) 73 { 74 return "drm_sched"; 75 } 76 77 static const char *drm_sched_fence_get_timeline_name(struct dma_fence *f) 78 { 79 struct drm_sched_fence *fence = to_drm_sched_fence(f); 80 return (const char *)fence->sched->name; 81 } 82 83 static void drm_sched_fence_free_rcu(struct rcu_head *rcu) 84 { 85 struct dma_fence *f = container_of(rcu, struct dma_fence, rcu); 86 struct drm_sched_fence *fence = to_drm_sched_fence(f); 87 88 if (!WARN_ON_ONCE(!fence)) { 89 #ifdef __linux__ 90 kmem_cache_free(sched_fence_slab, fence); 91 #else 92 pool_put(&sched_fence_slab, fence); 93 #endif 94 } 95 } 96 97 /** 98 * drm_sched_fence_free - free up an uninitialized fence 99 * 100 * @fence: fence to free 101 * 102 * Free up the fence memory. Should only be used if drm_sched_fence_init() 103 * has not been called yet. 104 */ 105 void drm_sched_fence_free(struct drm_sched_fence *fence) 106 { 107 /* This function should not be called if the fence has been initialized. */ 108 if (!WARN_ON_ONCE(fence->sched)) { 109 #ifdef __linux__ 110 kmem_cache_free(sched_fence_slab, fence); 111 #else 112 pool_put(&sched_fence_slab, fence); 113 #endif 114 } 115 } 116 117 /** 118 * drm_sched_fence_release_scheduled - callback that fence can be freed 119 * 120 * @f: fence 121 * 122 * This function is called when the reference count becomes zero. 123 * It just RCU schedules freeing up the fence. 124 */ 125 static void drm_sched_fence_release_scheduled(struct dma_fence *f) 126 { 127 struct drm_sched_fence *fence = to_drm_sched_fence(f); 128 129 dma_fence_put(fence->parent); 130 call_rcu(&fence->finished.rcu, drm_sched_fence_free_rcu); 131 } 132 133 /** 134 * drm_sched_fence_release_finished - drop extra reference 135 * 136 * @f: fence 137 * 138 * Drop the extra reference from the scheduled fence to the base fence. 139 */ 140 static void drm_sched_fence_release_finished(struct dma_fence *f) 141 { 142 struct drm_sched_fence *fence = to_drm_sched_fence(f); 143 144 dma_fence_put(&fence->scheduled); 145 } 146 147 static const struct dma_fence_ops drm_sched_fence_ops_scheduled = { 148 .get_driver_name = drm_sched_fence_get_driver_name, 149 .get_timeline_name = drm_sched_fence_get_timeline_name, 150 .release = drm_sched_fence_release_scheduled, 151 }; 152 153 static const struct dma_fence_ops drm_sched_fence_ops_finished = { 154 .get_driver_name = drm_sched_fence_get_driver_name, 155 .get_timeline_name = drm_sched_fence_get_timeline_name, 156 .release = drm_sched_fence_release_finished, 157 }; 158 159 struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f) 160 { 161 if (f->ops == &drm_sched_fence_ops_scheduled) 162 return container_of(f, struct drm_sched_fence, scheduled); 163 164 if (f->ops == &drm_sched_fence_ops_finished) 165 return container_of(f, struct drm_sched_fence, finished); 166 167 return NULL; 168 } 169 EXPORT_SYMBOL(to_drm_sched_fence); 170 171 struct drm_sched_fence *drm_sched_fence_alloc(struct drm_sched_entity *entity, 172 void *owner) 173 { 174 struct drm_sched_fence *fence = NULL; 175 176 #ifdef __linux__ 177 fence = kmem_cache_zalloc(sched_fence_slab, GFP_KERNEL); 178 #else 179 fence = pool_get(&sched_fence_slab, PR_WAITOK | PR_ZERO); 180 #endif 181 if (fence == NULL) 182 return NULL; 183 184 fence->owner = owner; 185 mtx_init(&fence->lock, IPL_TTY); 186 187 return fence; 188 } 189 190 void drm_sched_fence_init(struct drm_sched_fence *fence, 191 struct drm_sched_entity *entity) 192 { 193 unsigned seq; 194 195 fence->sched = entity->rq->sched; 196 seq = atomic_inc_return(&entity->fence_seq); 197 dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled, 198 &fence->lock, entity->fence_context, seq); 199 dma_fence_init(&fence->finished, &drm_sched_fence_ops_finished, 200 &fence->lock, entity->fence_context + 1, seq); 201 } 202 203 module_init(drm_sched_fence_slab_init); 204 module_exit(drm_sched_fence_slab_fini); 205 206 MODULE_DESCRIPTION("DRM GPU scheduler"); 207 MODULE_LICENSE("GPL and additional rights"); 208