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 "amdgpu.h"
32 #include "amdgpu_trace.h"
33 #include "amdgpu_amdkfd.h"
34 
35 struct amdgpu_sync_entry {
36 	struct hlist_node	node;
37 	struct dma_fence	*fence;
38 };
39 
40 static struct kmem_cache *amdgpu_sync_slab;
41 
42 /**
43  * amdgpu_sync_create - zero init sync object
44  *
45  * @sync: sync object to initialize
46  *
47  * Just clear the sync object for now.
48  */
49 void amdgpu_sync_create(struct amdgpu_sync *sync)
50 {
51 	hash_init(sync->fences);
52 	sync->last_vm_update = NULL;
53 }
54 
55 /**
56  * amdgpu_sync_same_dev - test if fence belong to us
57  *
58  * @adev: amdgpu device to use for the test
59  * @f: fence to test
60  *
61  * Test if the fence was issued by us.
62  */
63 static bool amdgpu_sync_same_dev(struct amdgpu_device *adev,
64 				 struct dma_fence *f)
65 {
66 	struct drm_sched_fence *s_fence = to_drm_sched_fence(f);
67 
68 	if (s_fence) {
69 		struct amdgpu_ring *ring;
70 
71 		ring = container_of(s_fence->sched, struct amdgpu_ring, sched);
72 		return ring->adev == adev;
73 	}
74 
75 	return false;
76 }
77 
78 /**
79  * amdgpu_sync_get_owner - extract the owner of a fence
80  *
81  * @f: fence get the owner from
82  *
83  * Extract who originally created the fence.
84  */
85 static void *amdgpu_sync_get_owner(struct dma_fence *f)
86 {
87 	struct drm_sched_fence *s_fence;
88 	struct amdgpu_amdkfd_fence *kfd_fence;
89 
90 	if (!f)
91 		return AMDGPU_FENCE_OWNER_UNDEFINED;
92 
93 	s_fence = to_drm_sched_fence(f);
94 	if (s_fence)
95 		return s_fence->owner;
96 
97 	kfd_fence = to_amdgpu_amdkfd_fence(f);
98 	if (kfd_fence)
99 		return AMDGPU_FENCE_OWNER_KFD;
100 
101 	return AMDGPU_FENCE_OWNER_UNDEFINED;
102 }
103 
104 /**
105  * amdgpu_sync_keep_later - Keep the later fence
106  *
107  * @keep: existing fence to test
108  * @fence: new fence
109  *
110  * Either keep the existing fence or the new one, depending which one is later.
111  */
112 static void amdgpu_sync_keep_later(struct dma_fence **keep,
113 				   struct dma_fence *fence)
114 {
115 	if (*keep && dma_fence_is_later(*keep, fence))
116 		return;
117 
118 	dma_fence_put(*keep);
119 	*keep = dma_fence_get(fence);
120 }
121 
122 /**
123  * amdgpu_sync_add_later - add the fence to the hash
124  *
125  * @sync: sync object to add the fence to
126  * @f: fence to add
127  *
128  * Tries to add the fence to an existing hash entry. Returns true when an entry
129  * was found, false otherwise.
130  */
131 static bool amdgpu_sync_add_later(struct amdgpu_sync *sync, struct dma_fence *f)
132 {
133 	struct amdgpu_sync_entry *e;
134 
135 	hash_for_each_possible(sync->fences, e, node, f->context) {
136 		if (unlikely(e->fence->context != f->context))
137 			continue;
138 
139 		amdgpu_sync_keep_later(&e->fence, f);
140 		return true;
141 	}
142 	return false;
143 }
144 
145 /**
146  * amdgpu_sync_fence - remember to sync to this fence
147  *
148  * @sync: sync object to add fence to
149  * @f: fence to sync to
150  *
151  * Add the fence to the sync object.
152  */
153 int amdgpu_sync_fence(struct amdgpu_sync *sync, struct dma_fence *f)
154 {
155 	struct amdgpu_sync_entry *e;
156 
157 	if (!f)
158 		return 0;
159 
160 	if (amdgpu_sync_add_later(sync, f))
161 		return 0;
162 
163 	e = kmem_cache_alloc(amdgpu_sync_slab, GFP_KERNEL);
164 	if (!e)
165 		return -ENOMEM;
166 
167 	hash_add(sync->fences, &e->node, f->context);
168 	e->fence = dma_fence_get(f);
169 	return 0;
170 }
171 
172 /**
173  * amdgpu_sync_vm_fence - remember to sync to this VM fence
174  *
175  * @sync: sync object to add fence to
176  * @fence: the VM fence to add
177  *
178  * Add the fence to the sync object and remember it as VM update.
179  */
180 int amdgpu_sync_vm_fence(struct amdgpu_sync *sync, struct dma_fence *fence)
181 {
182 	if (!fence)
183 		return 0;
184 
185 	amdgpu_sync_keep_later(&sync->last_vm_update, fence);
186 	return amdgpu_sync_fence(sync, fence);
187 }
188 
189 /**
190  * amdgpu_sync_resv - sync to a reservation object
191  *
192  * @adev: amdgpu device
193  * @sync: sync object to add fences from reservation object to
194  * @resv: reservation object with embedded fence
195  * @mode: how owner affects which fences we sync to
196  * @owner: owner of the planned job submission
197  *
198  * Sync to the fence
199  */
200 int amdgpu_sync_resv(struct amdgpu_device *adev, struct amdgpu_sync *sync,
201 		     struct dma_resv *resv, enum amdgpu_sync_mode mode,
202 		     void *owner)
203 {
204 	struct dma_resv_list *flist;
205 	struct dma_fence *f;
206 	unsigned i;
207 	int r = 0;
208 
209 	if (resv == NULL)
210 		return -EINVAL;
211 
212 	/* always sync to the exclusive fence */
213 	f = dma_resv_get_excl(resv);
214 	r = amdgpu_sync_fence(sync, f);
215 
216 	flist = dma_resv_get_list(resv);
217 	if (!flist || r)
218 		return r;
219 
220 	for (i = 0; i < flist->shared_count; ++i) {
221 		void *fence_owner;
222 
223 		f = rcu_dereference_protected(flist->shared[i],
224 					      dma_resv_held(resv));
225 
226 		fence_owner = amdgpu_sync_get_owner(f);
227 
228 		/* Always sync to moves, no matter what */
229 		if (fence_owner == AMDGPU_FENCE_OWNER_UNDEFINED) {
230 			r = amdgpu_sync_fence(sync, f);
231 			if (r)
232 				break;
233 		}
234 
235 		/* We only want to trigger KFD eviction fences on
236 		 * evict or move jobs. Skip KFD fences otherwise.
237 		 */
238 		if (fence_owner == AMDGPU_FENCE_OWNER_KFD &&
239 		    owner != AMDGPU_FENCE_OWNER_UNDEFINED)
240 			continue;
241 
242 		/* Never sync to VM updates either. */
243 		if (fence_owner == AMDGPU_FENCE_OWNER_VM &&
244 		    owner != AMDGPU_FENCE_OWNER_UNDEFINED)
245 			continue;
246 
247 		/* Ignore fences depending on the sync mode */
248 		switch (mode) {
249 		case AMDGPU_SYNC_ALWAYS:
250 			break;
251 
252 		case AMDGPU_SYNC_NE_OWNER:
253 			if (amdgpu_sync_same_dev(adev, f) &&
254 			    fence_owner == owner)
255 				continue;
256 			break;
257 
258 		case AMDGPU_SYNC_EQ_OWNER:
259 			if (amdgpu_sync_same_dev(adev, f) &&
260 			    fence_owner != owner)
261 				continue;
262 			break;
263 
264 		case AMDGPU_SYNC_EXPLICIT:
265 			continue;
266 		}
267 
268 		WARN(debug_evictions && fence_owner == AMDGPU_FENCE_OWNER_KFD,
269 		     "Adding eviction fence to sync obj");
270 		r = amdgpu_sync_fence(sync, f);
271 		if (r)
272 			break;
273 	}
274 	return r;
275 }
276 
277 /**
278  * amdgpu_sync_peek_fence - get the next fence not signaled yet
279  *
280  * @sync: the sync object
281  * @ring: optional ring to use for test
282  *
283  * Returns the next fence not signaled yet without removing it from the sync
284  * object.
285  */
286 struct dma_fence *amdgpu_sync_peek_fence(struct amdgpu_sync *sync,
287 					 struct amdgpu_ring *ring)
288 {
289 	struct amdgpu_sync_entry *e;
290 	struct hlist_node *tmp;
291 	int i;
292 
293 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
294 		struct dma_fence *f = e->fence;
295 		struct drm_sched_fence *s_fence = to_drm_sched_fence(f);
296 
297 		if (dma_fence_is_signaled(f)) {
298 			hash_del(&e->node);
299 			dma_fence_put(f);
300 			kmem_cache_free(amdgpu_sync_slab, e);
301 			continue;
302 		}
303 		if (ring && s_fence) {
304 			/* For fences from the same ring it is sufficient
305 			 * when they are scheduled.
306 			 */
307 			if (s_fence->sched == &ring->sched) {
308 				if (dma_fence_is_signaled(&s_fence->scheduled))
309 					continue;
310 
311 				return &s_fence->scheduled;
312 			}
313 		}
314 
315 		return f;
316 	}
317 
318 	return NULL;
319 }
320 
321 /**
322  * amdgpu_sync_get_fence - get the next fence from the sync object
323  *
324  * @sync: sync object to use
325  *
326  * Get and removes the next fence from the sync object not signaled yet.
327  */
328 struct dma_fence *amdgpu_sync_get_fence(struct amdgpu_sync *sync)
329 {
330 	struct amdgpu_sync_entry *e;
331 	struct hlist_node *tmp;
332 	struct dma_fence *f;
333 	int i;
334 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
335 
336 		f = e->fence;
337 
338 		hash_del(&e->node);
339 		kmem_cache_free(amdgpu_sync_slab, e);
340 
341 		if (!dma_fence_is_signaled(f))
342 			return f;
343 
344 		dma_fence_put(f);
345 	}
346 	return NULL;
347 }
348 
349 /**
350  * amdgpu_sync_clone - clone a sync object
351  *
352  * @source: sync object to clone
353  * @clone: pointer to destination sync object
354  *
355  * Adds references to all unsignaled fences in @source to @clone. Also
356  * removes signaled fences from @source while at it.
357  */
358 int amdgpu_sync_clone(struct amdgpu_sync *source, struct amdgpu_sync *clone)
359 {
360 	struct amdgpu_sync_entry *e;
361 	struct hlist_node *tmp;
362 	struct dma_fence *f;
363 	int i, r;
364 
365 	hash_for_each_safe(source->fences, i, tmp, e, node) {
366 		f = e->fence;
367 		if (!dma_fence_is_signaled(f)) {
368 			r = amdgpu_sync_fence(clone, f);
369 			if (r)
370 				return r;
371 		} else {
372 			hash_del(&e->node);
373 			dma_fence_put(f);
374 			kmem_cache_free(amdgpu_sync_slab, e);
375 		}
376 	}
377 
378 	dma_fence_put(clone->last_vm_update);
379 	clone->last_vm_update = dma_fence_get(source->last_vm_update);
380 
381 	return 0;
382 }
383 
384 int amdgpu_sync_wait(struct amdgpu_sync *sync, bool intr)
385 {
386 	struct amdgpu_sync_entry *e;
387 	struct hlist_node *tmp;
388 	int i, r;
389 
390 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
391 		r = dma_fence_wait(e->fence, intr);
392 		if (r)
393 			return r;
394 
395 		hash_del(&e->node);
396 		dma_fence_put(e->fence);
397 		kmem_cache_free(amdgpu_sync_slab, e);
398 	}
399 
400 	return 0;
401 }
402 
403 /**
404  * amdgpu_sync_free - free the sync object
405  *
406  * @sync: sync object to use
407  *
408  * Free the sync object.
409  */
410 void amdgpu_sync_free(struct amdgpu_sync *sync)
411 {
412 	struct amdgpu_sync_entry *e;
413 	struct hlist_node *tmp;
414 	unsigned i;
415 
416 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
417 		hash_del(&e->node);
418 		dma_fence_put(e->fence);
419 		kmem_cache_free(amdgpu_sync_slab, e);
420 	}
421 
422 	dma_fence_put(sync->last_vm_update);
423 }
424 
425 /**
426  * amdgpu_sync_init - init sync object subsystem
427  *
428  * Allocate the slab allocator.
429  */
430 int amdgpu_sync_init(void)
431 {
432 	amdgpu_sync_slab = kmem_cache_create(
433 		"amdgpu_sync", sizeof(struct amdgpu_sync_entry), 0,
434 		SLAB_HWCACHE_ALIGN, NULL);
435 	if (!amdgpu_sync_slab)
436 		return -ENOMEM;
437 
438 	return 0;
439 }
440 
441 /**
442  * amdgpu_sync_fini - fini sync object subsystem
443  *
444  * Free the slab allocator.
445  */
446 void amdgpu_sync_fini(void)
447 {
448 	kmem_cache_destroy(amdgpu_sync_slab);
449 }
450