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 <linux/dma-fence-chain.h>
32 
33 #include "amdgpu.h"
34 #include "amdgpu_trace.h"
35 #include "amdgpu_amdkfd.h"
36 
37 struct amdgpu_sync_entry {
38 	struct hlist_node	node;
39 	struct dma_fence	*fence;
40 };
41 
42 static struct kmem_cache *amdgpu_sync_slab;
43 
44 /**
45  * amdgpu_sync_create - zero init sync object
46  *
47  * @sync: sync object to initialize
48  *
49  * Just clear the sync object for now.
50  */
51 void amdgpu_sync_create(struct amdgpu_sync *sync)
52 {
53 	hash_init(sync->fences);
54 	sync->last_vm_update = NULL;
55 }
56 
57 /**
58  * amdgpu_sync_same_dev - test if fence belong to us
59  *
60  * @adev: amdgpu device to use for the test
61  * @f: fence to test
62  *
63  * Test if the fence was issued by us.
64  */
65 static bool amdgpu_sync_same_dev(struct amdgpu_device *adev,
66 				 struct dma_fence *f)
67 {
68 	struct drm_sched_fence *s_fence = to_drm_sched_fence(f);
69 
70 	if (s_fence) {
71 		struct amdgpu_ring *ring;
72 
73 		ring = container_of(s_fence->sched, struct amdgpu_ring, sched);
74 		return ring->adev == adev;
75 	}
76 
77 	return false;
78 }
79 
80 /**
81  * amdgpu_sync_get_owner - extract the owner of a fence
82  *
83  * @f: fence get the owner from
84  *
85  * Extract who originally created the fence.
86  */
87 static void *amdgpu_sync_get_owner(struct dma_fence *f)
88 {
89 	struct drm_sched_fence *s_fence;
90 	struct amdgpu_amdkfd_fence *kfd_fence;
91 
92 	if (!f)
93 		return AMDGPU_FENCE_OWNER_UNDEFINED;
94 
95 	s_fence = to_drm_sched_fence(f);
96 	if (s_fence)
97 		return s_fence->owner;
98 
99 	kfd_fence = to_amdgpu_amdkfd_fence(f);
100 	if (kfd_fence)
101 		return AMDGPU_FENCE_OWNER_KFD;
102 
103 	return AMDGPU_FENCE_OWNER_UNDEFINED;
104 }
105 
106 /**
107  * amdgpu_sync_keep_later - Keep the later fence
108  *
109  * @keep: existing fence to test
110  * @fence: new fence
111  *
112  * Either keep the existing fence or the new one, depending which one is later.
113  */
114 static void amdgpu_sync_keep_later(struct dma_fence **keep,
115 				   struct dma_fence *fence)
116 {
117 	if (*keep && dma_fence_is_later(*keep, fence))
118 		return;
119 
120 	dma_fence_put(*keep);
121 	*keep = dma_fence_get(fence);
122 }
123 
124 /**
125  * amdgpu_sync_add_later - add the fence to the hash
126  *
127  * @sync: sync object to add the fence to
128  * @f: fence to add
129  *
130  * Tries to add the fence to an existing hash entry. Returns true when an entry
131  * was found, false otherwise.
132  */
133 static bool amdgpu_sync_add_later(struct amdgpu_sync *sync, struct dma_fence *f)
134 {
135 	struct amdgpu_sync_entry *e;
136 
137 	hash_for_each_possible(sync->fences, e, node, f->context) {
138 		if (unlikely(e->fence->context != f->context))
139 			continue;
140 
141 		amdgpu_sync_keep_later(&e->fence, f);
142 		return true;
143 	}
144 	return false;
145 }
146 
147 /**
148  * amdgpu_sync_fence - remember to sync to this fence
149  *
150  * @sync: sync object to add fence to
151  * @f: fence to sync to
152  *
153  * Add the fence to the sync object.
154  */
155 int amdgpu_sync_fence(struct amdgpu_sync *sync, struct dma_fence *f)
156 {
157 	struct amdgpu_sync_entry *e;
158 
159 	if (!f)
160 		return 0;
161 
162 	if (amdgpu_sync_add_later(sync, f))
163 		return 0;
164 
165 	e = kmem_cache_alloc(amdgpu_sync_slab, GFP_KERNEL);
166 	if (!e)
167 		return -ENOMEM;
168 
169 	hash_add(sync->fences, &e->node, f->context);
170 	e->fence = dma_fence_get(f);
171 	return 0;
172 }
173 
174 /**
175  * amdgpu_sync_vm_fence - remember to sync to this VM fence
176  *
177  * @sync: sync object to add fence to
178  * @fence: the VM fence to add
179  *
180  * Add the fence to the sync object and remember it as VM update.
181  */
182 int amdgpu_sync_vm_fence(struct amdgpu_sync *sync, struct dma_fence *fence)
183 {
184 	if (!fence)
185 		return 0;
186 
187 	amdgpu_sync_keep_later(&sync->last_vm_update, fence);
188 	return amdgpu_sync_fence(sync, fence);
189 }
190 
191 /* Determine based on the owner and mode if we should sync to a fence or not */
192 static bool amdgpu_sync_test_fence(struct amdgpu_device *adev,
193 				   enum amdgpu_sync_mode mode,
194 				   void *owner, struct dma_fence *f)
195 {
196 	void *fence_owner = amdgpu_sync_get_owner(f);
197 
198 	/* Always sync to moves, no matter what */
199 	if (fence_owner == AMDGPU_FENCE_OWNER_UNDEFINED)
200 		return true;
201 
202 	/* We only want to trigger KFD eviction fences on
203 	 * evict or move jobs. Skip KFD fences otherwise.
204 	 */
205 	if (fence_owner == AMDGPU_FENCE_OWNER_KFD &&
206 	    owner != AMDGPU_FENCE_OWNER_UNDEFINED)
207 		return false;
208 
209 	/* Never sync to VM updates either. */
210 	if (fence_owner == AMDGPU_FENCE_OWNER_VM &&
211 	    owner != AMDGPU_FENCE_OWNER_UNDEFINED)
212 		return false;
213 
214 	/* Ignore fences depending on the sync mode */
215 	switch (mode) {
216 	case AMDGPU_SYNC_ALWAYS:
217 		return true;
218 
219 	case AMDGPU_SYNC_NE_OWNER:
220 		if (amdgpu_sync_same_dev(adev, f) &&
221 		    fence_owner == owner)
222 			return false;
223 		break;
224 
225 	case AMDGPU_SYNC_EQ_OWNER:
226 		if (amdgpu_sync_same_dev(adev, f) &&
227 		    fence_owner != owner)
228 			return false;
229 		break;
230 
231 	case AMDGPU_SYNC_EXPLICIT:
232 		return false;
233 	}
234 
235 	WARN(debug_evictions && fence_owner == AMDGPU_FENCE_OWNER_KFD,
236 	     "Adding eviction fence to sync obj");
237 	return true;
238 }
239 
240 /**
241  * amdgpu_sync_resv - sync to a reservation object
242  *
243  * @adev: amdgpu device
244  * @sync: sync object to add fences from reservation object to
245  * @resv: reservation object with embedded fence
246  * @mode: how owner affects which fences we sync to
247  * @owner: owner of the planned job submission
248  *
249  * Sync to the fence
250  */
251 int amdgpu_sync_resv(struct amdgpu_device *adev, struct amdgpu_sync *sync,
252 		     struct dma_resv *resv, enum amdgpu_sync_mode mode,
253 		     void *owner)
254 {
255 	struct dma_resv_iter cursor;
256 	struct dma_fence *f;
257 	int r;
258 
259 	if (resv == NULL)
260 		return -EINVAL;
261 
262 	dma_resv_for_each_fence(&cursor, resv, true, f) {
263 		dma_fence_chain_for_each(f, f) {
264 			struct dma_fence *tmp = dma_fence_chain_contained(f);
265 
266 			if (amdgpu_sync_test_fence(adev, mode, owner, tmp)) {
267 				r = amdgpu_sync_fence(sync, f);
268 				dma_fence_put(f);
269 				if (r)
270 					return r;
271 				break;
272 			}
273 		}
274 	}
275 	return 0;
276 }
277 
278 /**
279  * amdgpu_sync_peek_fence - get the next fence not signaled yet
280  *
281  * @sync: the sync object
282  * @ring: optional ring to use for test
283  *
284  * Returns the next fence not signaled yet without removing it from the sync
285  * object.
286  */
287 struct dma_fence *amdgpu_sync_peek_fence(struct amdgpu_sync *sync,
288 					 struct amdgpu_ring *ring)
289 {
290 	struct amdgpu_sync_entry *e;
291 	struct hlist_node *tmp;
292 	int i;
293 
294 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
295 		struct dma_fence *f = e->fence;
296 		struct drm_sched_fence *s_fence = to_drm_sched_fence(f);
297 
298 		if (dma_fence_is_signaled(f)) {
299 			hash_del(&e->node);
300 			dma_fence_put(f);
301 			kmem_cache_free(amdgpu_sync_slab, e);
302 			continue;
303 		}
304 		if (ring && s_fence) {
305 			/* For fences from the same ring it is sufficient
306 			 * when they are scheduled.
307 			 */
308 			if (s_fence->sched == &ring->sched) {
309 				if (dma_fence_is_signaled(&s_fence->scheduled))
310 					continue;
311 
312 				return &s_fence->scheduled;
313 			}
314 		}
315 
316 		return f;
317 	}
318 
319 	return NULL;
320 }
321 
322 /**
323  * amdgpu_sync_get_fence - get the next fence from the sync object
324  *
325  * @sync: sync object to use
326  *
327  * Get and removes the next fence from the sync object not signaled yet.
328  */
329 struct dma_fence *amdgpu_sync_get_fence(struct amdgpu_sync *sync)
330 {
331 	struct amdgpu_sync_entry *e;
332 	struct hlist_node *tmp;
333 	struct dma_fence *f;
334 	int i;
335 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
336 
337 		f = e->fence;
338 
339 		hash_del(&e->node);
340 		kmem_cache_free(amdgpu_sync_slab, e);
341 
342 		if (!dma_fence_is_signaled(f))
343 			return f;
344 
345 		dma_fence_put(f);
346 	}
347 	return NULL;
348 }
349 
350 /**
351  * amdgpu_sync_clone - clone a sync object
352  *
353  * @source: sync object to clone
354  * @clone: pointer to destination sync object
355  *
356  * Adds references to all unsignaled fences in @source to @clone. Also
357  * removes signaled fences from @source while at it.
358  */
359 int amdgpu_sync_clone(struct amdgpu_sync *source, struct amdgpu_sync *clone)
360 {
361 	struct amdgpu_sync_entry *e;
362 	struct hlist_node *tmp;
363 	struct dma_fence *f;
364 	int i, r;
365 
366 	hash_for_each_safe(source->fences, i, tmp, e, node) {
367 		f = e->fence;
368 		if (!dma_fence_is_signaled(f)) {
369 			r = amdgpu_sync_fence(clone, f);
370 			if (r)
371 				return r;
372 		} else {
373 			hash_del(&e->node);
374 			dma_fence_put(f);
375 			kmem_cache_free(amdgpu_sync_slab, e);
376 		}
377 	}
378 
379 	dma_fence_put(clone->last_vm_update);
380 	clone->last_vm_update = dma_fence_get(source->last_vm_update);
381 
382 	return 0;
383 }
384 
385 int amdgpu_sync_wait(struct amdgpu_sync *sync, bool intr)
386 {
387 	struct amdgpu_sync_entry *e;
388 	struct hlist_node *tmp;
389 	int i, r;
390 
391 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
392 		r = dma_fence_wait(e->fence, intr);
393 		if (r)
394 			return r;
395 
396 		hash_del(&e->node);
397 		dma_fence_put(e->fence);
398 		kmem_cache_free(amdgpu_sync_slab, e);
399 	}
400 
401 	return 0;
402 }
403 
404 /**
405  * amdgpu_sync_free - free the sync object
406  *
407  * @sync: sync object to use
408  *
409  * Free the sync object.
410  */
411 void amdgpu_sync_free(struct amdgpu_sync *sync)
412 {
413 	struct amdgpu_sync_entry *e;
414 	struct hlist_node *tmp;
415 	unsigned i;
416 
417 	hash_for_each_safe(sync->fences, i, tmp, e, node) {
418 		hash_del(&e->node);
419 		dma_fence_put(e->fence);
420 		kmem_cache_free(amdgpu_sync_slab, e);
421 	}
422 
423 	dma_fence_put(sync->last_vm_update);
424 }
425 
426 /**
427  * amdgpu_sync_init - init sync object subsystem
428  *
429  * Allocate the slab allocator.
430  */
431 int amdgpu_sync_init(void)
432 {
433 	amdgpu_sync_slab = kmem_cache_create(
434 		"amdgpu_sync", sizeof(struct amdgpu_sync_entry), 0,
435 		SLAB_HWCACHE_ALIGN, NULL);
436 	if (!amdgpu_sync_slab)
437 		return -ENOMEM;
438 
439 	return 0;
440 }
441 
442 /**
443  * amdgpu_sync_fini - fini sync object subsystem
444  *
445  * Free the slab allocator.
446  */
447 void amdgpu_sync_fini(void)
448 {
449 	kmem_cache_destroy(amdgpu_sync_slab);
450 }
451