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_NONE, 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 int ret = dma_fence_signal(&fence->scheduled); 65 66 if (!ret) 67 DMA_FENCE_TRACE(&fence->scheduled, 68 "signaled from irq context\n"); 69 else 70 DMA_FENCE_TRACE(&fence->scheduled, 71 "was already signaled\n"); 72 } 73 74 void drm_sched_fence_finished(struct drm_sched_fence *fence) 75 { 76 int ret = dma_fence_signal(&fence->finished); 77 78 if (!ret) 79 DMA_FENCE_TRACE(&fence->finished, 80 "signaled from irq context\n"); 81 else 82 DMA_FENCE_TRACE(&fence->finished, 83 "was already signaled\n"); 84 } 85 86 static const char *drm_sched_fence_get_driver_name(struct dma_fence *fence) 87 { 88 return "drm_sched"; 89 } 90 91 static const char *drm_sched_fence_get_timeline_name(struct dma_fence *f) 92 { 93 struct drm_sched_fence *fence = to_drm_sched_fence(f); 94 return (const char *)fence->sched->name; 95 } 96 97 /** 98 * drm_sched_fence_free - free up the fence memory 99 * 100 * @rcu: RCU callback head 101 * 102 * Free up the fence memory after the RCU grace period. 103 */ 104 static void drm_sched_fence_free(struct rcu_head *rcu) 105 { 106 struct dma_fence *f = container_of(rcu, struct dma_fence, rcu); 107 struct drm_sched_fence *fence = to_drm_sched_fence(f); 108 109 #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 * drm_sched_fence_release_scheduled - callback that fence can be freed 118 * 119 * @f: fence 120 * 121 * This function is called when the reference count becomes zero. 122 * It just RCU schedules freeing up the fence. 123 */ 124 static void drm_sched_fence_release_scheduled(struct dma_fence *f) 125 { 126 struct drm_sched_fence *fence = to_drm_sched_fence(f); 127 128 dma_fence_put(fence->parent); 129 call_rcu(&fence->finished.rcu, drm_sched_fence_free); 130 } 131 132 /** 133 * drm_sched_fence_release_finished - drop extra reference 134 * 135 * @f: fence 136 * 137 * Drop the extra reference from the scheduled fence to the base fence. 138 */ 139 static void drm_sched_fence_release_finished(struct dma_fence *f) 140 { 141 struct drm_sched_fence *fence = to_drm_sched_fence(f); 142 143 dma_fence_put(&fence->scheduled); 144 } 145 146 static const struct dma_fence_ops drm_sched_fence_ops_scheduled = { 147 .get_driver_name = drm_sched_fence_get_driver_name, 148 .get_timeline_name = drm_sched_fence_get_timeline_name, 149 .release = drm_sched_fence_release_scheduled, 150 }; 151 152 static const struct dma_fence_ops drm_sched_fence_ops_finished = { 153 .get_driver_name = drm_sched_fence_get_driver_name, 154 .get_timeline_name = drm_sched_fence_get_timeline_name, 155 .release = drm_sched_fence_release_finished, 156 }; 157 158 struct drm_sched_fence *to_drm_sched_fence(struct dma_fence *f) 159 { 160 if (f->ops == &drm_sched_fence_ops_scheduled) 161 return container_of(f, struct drm_sched_fence, scheduled); 162 163 if (f->ops == &drm_sched_fence_ops_finished) 164 return container_of(f, struct drm_sched_fence, finished); 165 166 return NULL; 167 } 168 EXPORT_SYMBOL(to_drm_sched_fence); 169 170 struct drm_sched_fence *drm_sched_fence_create(struct drm_sched_entity *entity, 171 void *owner) 172 { 173 struct drm_sched_fence *fence = NULL; 174 unsigned seq; 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 fence->sched = entity->rq->sched; 186 mtx_init(&fence->lock, IPL_TTY); 187 188 seq = atomic_inc_return(&entity->fence_seq); 189 dma_fence_init(&fence->scheduled, &drm_sched_fence_ops_scheduled, 190 &fence->lock, entity->fence_context, seq); 191 dma_fence_init(&fence->finished, &drm_sched_fence_ops_finished, 192 &fence->lock, entity->fence_context + 1, seq); 193 194 return fence; 195 } 196 197 module_init(drm_sched_fence_slab_init); 198 module_exit(drm_sched_fence_slab_fini); 199 200 MODULE_DESCRIPTION("DRM GPU scheduler"); 201 MODULE_LICENSE("GPL and additional rights"); 202