drivers/gpu/drm/amd/amdgpu/amdgpu_sync.c

   1 /*
   2  * Copyright 2014 Advanced Micro Devices, Inc.
   3  * All Rights Reserved.
   4  *
   5  * Permission is hereby granted, free of charge, to any person obtaining a
   6  * copy of this software and associated documentation files (the
   7  * "Software"), to deal in the Software without restriction, including
   8  * without limitation the rights to use, copy, modify, merge, publish,
   9  * distribute, sub license, and/or sell copies of the Software, and to
  10  * permit persons to whom the Software is furnished to do so, subject to
  11  * the following conditions:
  12  *
  13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  15  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
  16  * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
  17  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
  18  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
  19  * USE OR OTHER DEALINGS IN THE SOFTWARE.
  20  *
  21  * The above copyright notice and this permission notice (including the
  22  * next paragraph) shall be included in all copies or substantial portions
  23  * of the Software.
  24  *
  25  */
  26 /*
  27  * Authors:
  28  *    Christian König <christian.koenig@amd.com>
  29  */
  30
  31 #include <drm/drmP.h>
  32 #include "amdgpu.h"
  33 #include "amdgpu_trace.h"
  34
  35 struct amdgpu_sync_entry {
  36         struct hlist_node       node;
  37         struct fence            *fence;
  38 };
  39
  40 /**
  41  * amdgpu_sync_create - zero init sync object
  42  *
  43  * @sync: sync object to initialize
  44  *
  45  * Just clear the sync object for now.
  46  */
  47 void amdgpu_sync_create(struct amdgpu_sync *sync)
  48 {
  49         unsigned i;
  50
  51         for (i = 0; i < AMDGPU_NUM_SYNCS; ++i)
  52                 sync->semaphores[i] = NULL;
  53
  54         for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
  55                 sync->sync_to[i] = NULL;
  56
  57         hash_init(sync->fences);
  58         sync->last_vm_update = NULL;
  59 }
  60
  61 static bool amdgpu_sync_same_dev(struct amdgpu_device *adev, struct fence *f)
  62 {
  63         struct amdgpu_fence *a_fence = to_amdgpu_fence(f);
  64         struct amd_sched_fence *s_fence = to_amd_sched_fence(f);
  65
  66         if (a_fence)
  67                 return a_fence->ring->adev == adev;
  68
  69         if (s_fence) {
  70                 struct amdgpu_ring *ring;
  71
  72                 ring = container_of(s_fence->sched, struct amdgpu_ring, sched);
  73                 return ring->adev == adev;
  74         }
  75
  76         return false;
  77 }
  78
  79 static bool amdgpu_sync_test_owner(struct fence *f, void *owner)
  80 {
  81         struct amdgpu_fence *a_fence = to_amdgpu_fence(f);
  82         struct amd_sched_fence *s_fence = to_amd_sched_fence(f);
  83         if (s_fence)
  84                 return s_fence->owner == owner;
  85         if (a_fence)
  86                 return a_fence->owner == owner;
  87         return false;
  88 }
  89
  90 /**
  91  * amdgpu_sync_fence - remember to sync to this fence
  92  *
  93  * @sync: sync object to add fence to
  94  * @fence: fence to sync to
  95  *
  96  */
  97 int amdgpu_sync_fence(struct amdgpu_device *adev, struct amdgpu_sync *sync,
  98                       struct fence *f)
  99 {
 100         struct amdgpu_sync_entry *e;
 101         struct amdgpu_fence *fence;
 102         struct amdgpu_fence *other;
 103         struct fence *tmp, *later;
 104
 105         if (!f)
 106                 return 0;
 107
 108         if (amdgpu_sync_same_dev(adev, f) &&
 109             amdgpu_sync_test_owner(f, AMDGPU_FENCE_OWNER_VM)) {
 110                 if (sync->last_vm_update) {
 111                         tmp = sync->last_vm_update;
 112                         BUG_ON(f->context != tmp->context);
 113                         later = (f->seqno - tmp->seqno <= INT_MAX) ? f : tmp;
 114                         sync->last_vm_update = fence_get(later);
 115                         fence_put(tmp);
 116                 } else
 117                         sync->last_vm_update = fence_get(f);
 118         }
 119
 120         fence = to_amdgpu_fence(f);
 121         if (!fence || fence->ring->adev != adev) {
 122                 hash_for_each_possible(sync->fences, e, node, f->context) {
 123                         struct fence *new;
 124                         if (unlikely(e->fence->context != f->context))
 125                                 continue;
 126                         new = fence_get(fence_later(e->fence, f));
 127                         if (new) {
 128                                 fence_put(e->fence);
 129                                 e->fence = new;
 130                         }
 131                         return 0;
 132                 }
 133
 134                 e = kmalloc(sizeof(struct amdgpu_sync_entry), GFP_KERNEL);
 135                 if (!e)
 136                         return -ENOMEM;
 137
 138                 hash_add(sync->fences, &e->node, f->context);
 139                 e->fence = fence_get(f);
 140                 return 0;
 141         }
 142
 143         other = sync->sync_to[fence->ring->idx];
 144         sync->sync_to[fence->ring->idx] = amdgpu_fence_ref(
 145                 amdgpu_fence_later(fence, other));
 146         amdgpu_fence_unref(&other);
 147
 148         return 0;
 149 }
 150
 151 static void *amdgpu_sync_get_owner(struct fence *f)
 152 {
 153         struct amdgpu_fence *a_fence = to_amdgpu_fence(f);
 154         struct amd_sched_fence *s_fence = to_amd_sched_fence(f);
 155
 156         if (s_fence)
 157                 return s_fence->owner;
 158         else if (a_fence)
 159                 return a_fence->owner;
 160         return AMDGPU_FENCE_OWNER_UNDEFINED;
 161 }
 162
 163 /**
 164  * amdgpu_sync_resv - use the semaphores to sync to a reservation object
 165  *
 166  * @sync: sync object to add fences from reservation object to
 167  * @resv: reservation object with embedded fence
 168  * @shared: true if we should only sync to the exclusive fence
 169  *
 170  * Sync to the fence using the semaphore objects
 171  */
 172 int amdgpu_sync_resv(struct amdgpu_device *adev,
 173                      struct amdgpu_sync *sync,
 174                      struct reservation_object *resv,
 175                      void *owner)
 176 {
 177         struct reservation_object_list *flist;
 178         struct fence *f;
 179         void *fence_owner;
 180         unsigned i;
 181         int r = 0;
 182
 183         if (resv == NULL)
 184                 return -EINVAL;
 185
 186         /* always sync to the exclusive fence */
 187         f = reservation_object_get_excl(resv);
 188         r = amdgpu_sync_fence(adev, sync, f);
 189
 190         flist = reservation_object_get_list(resv);
 191         if (!flist || r)
 192                 return r;
 193
 194         for (i = 0; i < flist->shared_count; ++i) {
 195                 f = rcu_dereference_protected(flist->shared[i],
 196                                               reservation_object_held(resv));
 197                 if (amdgpu_sync_same_dev(adev, f)) {
 198                         /* VM updates are only interesting
 199                          * for other VM updates and moves.
 200                          */
 201                         fence_owner = amdgpu_sync_get_owner(f);
 202                         if ((owner != AMDGPU_FENCE_OWNER_MOVE) &&
 203                             (fence_owner != AMDGPU_FENCE_OWNER_MOVE) &&
 204                             ((owner == AMDGPU_FENCE_OWNER_VM) !=
 205                              (fence_owner == AMDGPU_FENCE_OWNER_VM)))
 206                                 continue;
 207
 208                         /* Ignore fence from the same owner as
 209                          * long as it isn't undefined.
 210                          */
 211                         if (owner != AMDGPU_FENCE_OWNER_UNDEFINED &&
 212                             fence_owner == owner)
 213                                 continue;
 214                 }
 215
 216                 r = amdgpu_sync_fence(adev, sync, f);
 217                 if (r)
 218                         break;
 219         }
 220         return r;
 221 }
 222
 223 struct fence *amdgpu_sync_get_fence(struct amdgpu_sync *sync)
 224 {
 225         struct amdgpu_sync_entry *e;
 226         struct hlist_node *tmp;
 227         struct fence *f;
 228         int i;
 229
 230         hash_for_each_safe(sync->fences, i, tmp, e, node) {
 231
 232                 f = e->fence;
 233
 234                 hash_del(&e->node);
 235                 kfree(e);
 236
 237                 if (!fence_is_signaled(f))
 238                         return f;
 239
 240                 fence_put(f);
 241         }
 242         return NULL;
 243 }
 244
 245 int amdgpu_sync_wait(struct amdgpu_sync *sync)
 246 {
 247         struct amdgpu_sync_entry *e;
 248         struct hlist_node *tmp;
 249         int i, r;
 250
 251         hash_for_each_safe(sync->fences, i, tmp, e, node) {
 252                 r = fence_wait(e->fence, false);
 253                 if (r)
 254                         return r;
 255
 256                 hash_del(&e->node);
 257                 fence_put(e->fence);
 258                 kfree(e);
 259         }
 260
 261         if (amdgpu_enable_semaphores)
 262                 return 0;
 263
 264         for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 265                 struct amdgpu_fence *fence = sync->sync_to[i];
 266                 if (!fence)
 267                         continue;
 268
 269                 r = fence_wait(&fence->base, false);
 270                 if (r)
 271                         return r;
 272         }
 273
 274         return 0;
 275 }
 276
 277 /**
 278  * amdgpu_sync_rings - sync ring to all registered fences
 279  *
 280  * @sync: sync object to use
 281  * @ring: ring that needs sync
 282  *
 283  * Ensure that all registered fences are signaled before letting
 284  * the ring continue. The caller must hold the ring lock.
 285  */
 286 int amdgpu_sync_rings(struct amdgpu_sync *sync,
 287                       struct amdgpu_ring *ring)
 288 {
 289         struct amdgpu_device *adev = ring->adev;
 290         unsigned count = 0;
 291         int i, r;
 292
 293         for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 294                 struct amdgpu_fence *fence = sync->sync_to[i];
 295                 struct amdgpu_semaphore *semaphore;
 296                 struct amdgpu_ring *other = adev->rings[i];
 297
 298                 /* check if we really need to sync */
 299                 if (!amdgpu_fence_need_sync(fence, ring))
 300                         continue;
 301
 302                 /* prevent GPU deadlocks */
 303                 if (!other->ready) {
 304                         dev_err(adev->dev, "Syncing to a disabled ring!");
 305                         return -EINVAL;
 306                 }
 307
 308                 if (amdgpu_enable_scheduler || !amdgpu_enable_semaphores ||
 309                     (count >= AMDGPU_NUM_SYNCS)) {
 310                         /* not enough room, wait manually */
 311                         r = fence_wait(&fence->base, false);
 312                         if (r)
 313                                 return r;
 314                         continue;
 315                 }
 316                 r = amdgpu_semaphore_create(adev, &semaphore);
 317                 if (r)
 318                         return r;
 319
 320                 sync->semaphores[count++] = semaphore;
 321
 322                 /* allocate enough space for sync command */
 323                 r = amdgpu_ring_alloc(other, 16);
 324                 if (r)
 325                         return r;
 326
 327                 /* emit the signal semaphore */
 328                 if (!amdgpu_semaphore_emit_signal(other, semaphore)) {
 329                         /* signaling wasn't successful wait manually */
 330                         amdgpu_ring_undo(other);
 331                         r = fence_wait(&fence->base, false);
 332                         if (r)
 333                                 return r;
 334                         continue;
 335                 }
 336
 337                 /* we assume caller has already allocated space on waiters ring */
 338                 if (!amdgpu_semaphore_emit_wait(ring, semaphore)) {
 339                         /* waiting wasn't successful wait manually */
 340                         amdgpu_ring_undo(other);
 341                         r = fence_wait(&fence->base, false);
 342                         if (r)
 343                                 return r;
 344                         continue;
 345                 }
 346
 347                 amdgpu_ring_commit(other);
 348                 amdgpu_fence_note_sync(fence, ring);
 349         }
 350
 351         return 0;
 352 }
 353
 354 /**
 355  * amdgpu_sync_free - free the sync object
 356  *
 357  * @adev: amdgpu_device pointer
 358  * @sync: sync object to use
 359  * @fence: fence to use for the free
 360  *
 361  * Free the sync object by freeing all semaphores in it.
 362  */
 363 void amdgpu_sync_free(struct amdgpu_device *adev,
 364                       struct amdgpu_sync *sync,
 365                       struct fence *fence)
 366 {
 367         struct amdgpu_sync_entry *e;
 368         struct hlist_node *tmp;
 369         unsigned i;
 370
 371         hash_for_each_safe(sync->fences, i, tmp, e, node) {
 372                 hash_del(&e->node);
 373                 fence_put(e->fence);
 374                 kfree(e);
 375         }
 376
 377         for (i = 0; i < AMDGPU_NUM_SYNCS; ++i)
 378                 amdgpu_semaphore_free(adev, &sync->semaphores[i], fence);
 379
 380         for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
 381                 amdgpu_fence_unref(&sync->sync_to[i]);
 382
 383         fence_put(sync->last_vm_update);
 384 }