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 /**
  36  * amdgpu_sync_create - zero init sync object
  37  *
  38  * @sync: sync object to initialize
  39  *
  40  * Just clear the sync object for now.
  41  */
  42 void amdgpu_sync_create(struct amdgpu_sync *sync)
  43 {
  44         unsigned i;
  45
  46         for (i = 0; i < AMDGPU_NUM_SYNCS; ++i)
  47                 sync->semaphores[i] = NULL;
  48
  49         for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
  50                 sync->sync_to[i] = NULL;
  51
  52         sync->last_vm_update = NULL;
  53 }
  54
  55 /**
  56  * amdgpu_sync_fence - remember to sync to this fence
  57  *
  58  * @sync: sync object to add fence to
  59  * @fence: fence to sync to
  60  *
  61  */
  62 int amdgpu_sync_fence(struct amdgpu_device *adev, struct amdgpu_sync *sync,
  63                       struct fence *f)
  64 {
  65         struct amdgpu_fence *fence;
  66         struct amdgpu_fence *other;
  67
  68         if (!f)
  69                 return 0;
  70
  71         fence = to_amdgpu_fence(f);
  72         if (!fence || fence->ring->adev != adev)
  73                 return fence_wait(f, true);
  74
  75         other = sync->sync_to[fence->ring->idx];
  76         sync->sync_to[fence->ring->idx] = amdgpu_fence_ref(
  77                 amdgpu_fence_later(fence, other));
  78         amdgpu_fence_unref(&other);
  79
  80         if (fence->owner == AMDGPU_FENCE_OWNER_VM) {
  81                 other = sync->last_vm_update;
  82                 sync->last_vm_update = amdgpu_fence_ref(
  83                         amdgpu_fence_later(fence, other));
  84                 amdgpu_fence_unref(&other);
  85         }
  86
  87         return 0;
  88 }
  89
  90 /**
  91  * amdgpu_sync_resv - use the semaphores to sync to a reservation object
  92  *
  93  * @sync: sync object to add fences from reservation object to
  94  * @resv: reservation object with embedded fence
  95  * @shared: true if we should only sync to the exclusive fence
  96  *
  97  * Sync to the fence using the semaphore objects
  98  */
  99 int amdgpu_sync_resv(struct amdgpu_device *adev,
 100                      struct amdgpu_sync *sync,
 101                      struct reservation_object *resv,
 102                      void *owner)
 103 {
 104         struct reservation_object_list *flist;
 105         struct fence *f;
 106         struct amdgpu_fence *fence;
 107         unsigned i;
 108         int r = 0;
 109
 110         if (resv == NULL)
 111                 return -EINVAL;
 112
 113         /* always sync to the exclusive fence */
 114         f = reservation_object_get_excl(resv);
 115         r = amdgpu_sync_fence(adev, sync, f);
 116
 117         flist = reservation_object_get_list(resv);
 118         if (!flist || r)
 119                 return r;
 120
 121         for (i = 0; i < flist->shared_count; ++i) {
 122                 f = rcu_dereference_protected(flist->shared[i],
 123                                               reservation_object_held(resv));
 124                 fence = f ? to_amdgpu_fence(f) : NULL;
 125                 if (fence && fence->ring->adev == adev) {
 126                         /* VM updates are only interesting
 127                          * for other VM updates and moves.
 128                          */
 129                         if ((owner != AMDGPU_FENCE_OWNER_MOVE) &&
 130                             (fence->owner != AMDGPU_FENCE_OWNER_MOVE) &&
 131                             ((owner == AMDGPU_FENCE_OWNER_VM) !=
 132                              (fence->owner == AMDGPU_FENCE_OWNER_VM)))
 133                                 continue;
 134
 135                         /* Ignore fence from the same owner as
 136                          * long as it isn't undefined.
 137                          */
 138                         if (owner != AMDGPU_FENCE_OWNER_UNDEFINED &&
 139                             fence->owner == owner)
 140                                 continue;
 141                 }
 142
 143                 r = amdgpu_sync_fence(adev, sync, f);
 144                 if (r)
 145                         break;
 146         }
 147         return r;
 148 }
 149
 150 /**
 151  * amdgpu_sync_rings - sync ring to all registered fences
 152  *
 153  * @sync: sync object to use
 154  * @ring: ring that needs sync
 155  *
 156  * Ensure that all registered fences are signaled before letting
 157  * the ring continue. The caller must hold the ring lock.
 158  */
 159 int amdgpu_sync_rings(struct amdgpu_sync *sync,
 160                       struct amdgpu_ring *ring)
 161 {
 162         struct amdgpu_device *adev = ring->adev;
 163         unsigned count = 0;
 164         int i, r;
 165
 166         for (i = 0; i < AMDGPU_MAX_RINGS; ++i) {
 167                 struct amdgpu_fence *fence = sync->sync_to[i];
 168                 struct amdgpu_semaphore *semaphore;
 169                 struct amdgpu_ring *other = adev->rings[i];
 170
 171                 /* check if we really need to sync */
 172                 if (!amdgpu_fence_need_sync(fence, ring))
 173                         continue;
 174
 175                 /* prevent GPU deadlocks */
 176                 if (!other->ready) {
 177                         dev_err(adev->dev, "Syncing to a disabled ring!");
 178                         return -EINVAL;
 179                 }
 180
 181                 if (amdgpu_enable_scheduler || (count >= AMDGPU_NUM_SYNCS)) {
 182                         /* not enough room, wait manually */
 183                         r = amdgpu_fence_wait(fence, false);
 184                         if (r)
 185                                 return r;
 186                         continue;
 187                 }
 188                 r = amdgpu_semaphore_create(adev, &semaphore);
 189                 if (r)
 190                         return r;
 191
 192                 sync->semaphores[count++] = semaphore;
 193
 194                 /* allocate enough space for sync command */
 195                 r = amdgpu_ring_alloc(other, 16);
 196                 if (r)
 197                         return r;
 198
 199                 /* emit the signal semaphore */
 200                 if (!amdgpu_semaphore_emit_signal(other, semaphore)) {
 201                         /* signaling wasn't successful wait manually */
 202                         amdgpu_ring_undo(other);
 203                         r = amdgpu_fence_wait(fence, false);
 204                         if (r)
 205                                 return r;
 206                         continue;
 207                 }
 208
 209                 /* we assume caller has already allocated space on waiters ring */
 210                 if (!amdgpu_semaphore_emit_wait(ring, semaphore)) {
 211                         /* waiting wasn't successful wait manually */
 212                         amdgpu_ring_undo(other);
 213                         r = amdgpu_fence_wait(fence, false);
 214                         if (r)
 215                                 return r;
 216                         continue;
 217                 }
 218
 219                 amdgpu_ring_commit(other);
 220                 amdgpu_fence_note_sync(fence, ring);
 221         }
 222
 223         return 0;
 224 }
 225
 226 /**
 227  * amdgpu_sync_free - free the sync object
 228  *
 229  * @adev: amdgpu_device pointer
 230  * @sync: sync object to use
 231  * @fence: fence to use for the free
 232  *
 233  * Free the sync object by freeing all semaphores in it.
 234  */
 235 void amdgpu_sync_free(struct amdgpu_device *adev,
 236                       struct amdgpu_sync *sync,
 237                       struct amdgpu_fence *fence)
 238 {
 239         unsigned i;
 240
 241         for (i = 0; i < AMDGPU_NUM_SYNCS; ++i)
 242                 amdgpu_semaphore_free(adev, &sync->semaphores[i], fence);
 243
 244         for (i = 0; i < AMDGPU_MAX_RINGS; ++i)
 245                 amdgpu_fence_unref(&sync->sync_to[i]);
 246
 247         amdgpu_fence_unref(&sync->last_vm_update);
 248 }