xref: /linux/drivers/gpu/drm/i915/gt/mock_engine.c (revision 288440de9e5fdb4a3ff73864850f080c1250fc81)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2016 Intel Corporation
4  */
5 
6 #include "gem/i915_gem_context.h"
7 #include "gt/intel_ring.h"
8 
9 #include "i915_drv.h"
10 #include "intel_context.h"
11 #include "intel_engine_pm.h"
12 
13 #include "mock_engine.h"
14 #include "selftests/mock_request.h"
15 
16 static int mock_timeline_pin(struct intel_timeline *tl)
17 {
18 	int err;
19 
20 	if (WARN_ON(!i915_gem_object_trylock(tl->hwsp_ggtt->obj, NULL)))
21 		return -EBUSY;
22 
23 	err = intel_timeline_pin_map(tl);
24 	i915_gem_object_unlock(tl->hwsp_ggtt->obj);
25 	if (err)
26 		return err;
27 
28 	atomic_inc(&tl->pin_count);
29 	return 0;
30 }
31 
32 static void mock_timeline_unpin(struct intel_timeline *tl)
33 {
34 	GEM_BUG_ON(!atomic_read(&tl->pin_count));
35 	atomic_dec(&tl->pin_count);
36 }
37 
38 static struct i915_vma *create_ring_vma(struct i915_ggtt *ggtt, int size)
39 {
40 	struct i915_address_space *vm = &ggtt->vm;
41 	struct drm_i915_private *i915 = vm->i915;
42 	struct drm_i915_gem_object *obj;
43 	struct i915_vma *vma;
44 
45 	obj = i915_gem_object_create_internal(i915, size);
46 	if (IS_ERR(obj))
47 		return ERR_CAST(obj);
48 
49 	vma = i915_vma_instance(obj, vm, NULL);
50 	if (IS_ERR(vma))
51 		goto err;
52 
53 	return vma;
54 
55 err:
56 	i915_gem_object_put(obj);
57 	return vma;
58 }
59 
60 static struct intel_ring *mock_ring(struct intel_engine_cs *engine)
61 {
62 	const unsigned long sz = PAGE_SIZE;
63 	struct intel_ring *ring;
64 
65 	ring = kzalloc(sizeof(*ring) + sz, GFP_KERNEL);
66 	if (!ring)
67 		return NULL;
68 
69 	kref_init(&ring->ref);
70 	ring->size = sz;
71 	ring->effective_size = sz;
72 	ring->vaddr = (void *)(ring + 1);
73 	atomic_set(&ring->pin_count, 1);
74 
75 	ring->vma = create_ring_vma(engine->gt->ggtt, PAGE_SIZE);
76 	if (IS_ERR(ring->vma)) {
77 		kfree(ring);
78 		return NULL;
79 	}
80 
81 	intel_ring_update_space(ring);
82 
83 	return ring;
84 }
85 
86 static void mock_ring_free(struct intel_ring *ring)
87 {
88 	i915_vma_put(ring->vma);
89 
90 	kfree(ring);
91 }
92 
93 static struct i915_request *first_request(struct mock_engine *engine)
94 {
95 	return list_first_entry_or_null(&engine->hw_queue,
96 					struct i915_request,
97 					mock.link);
98 }
99 
100 static void advance(struct i915_request *request)
101 {
102 	list_del_init(&request->mock.link);
103 	i915_request_mark_complete(request);
104 	GEM_BUG_ON(!i915_request_completed(request));
105 
106 	intel_engine_signal_breadcrumbs(request->engine);
107 }
108 
109 static void hw_delay_complete(struct timer_list *t)
110 {
111 	struct mock_engine *engine = from_timer(engine, t, hw_delay);
112 	struct i915_request *request;
113 	unsigned long flags;
114 
115 	spin_lock_irqsave(&engine->hw_lock, flags);
116 
117 	/* Timer fired, first request is complete */
118 	request = first_request(engine);
119 	if (request)
120 		advance(request);
121 
122 	/*
123 	 * Also immediately signal any subsequent 0-delay requests, but
124 	 * requeue the timer for the next delayed request.
125 	 */
126 	while ((request = first_request(engine))) {
127 		if (request->mock.delay) {
128 			mod_timer(&engine->hw_delay,
129 				  jiffies + request->mock.delay);
130 			break;
131 		}
132 
133 		advance(request);
134 	}
135 
136 	spin_unlock_irqrestore(&engine->hw_lock, flags);
137 }
138 
139 static void mock_context_unpin(struct intel_context *ce)
140 {
141 }
142 
143 static void mock_context_post_unpin(struct intel_context *ce)
144 {
145 	i915_vma_unpin(ce->ring->vma);
146 }
147 
148 static void mock_context_destroy(struct kref *ref)
149 {
150 	struct intel_context *ce = container_of(ref, typeof(*ce), ref);
151 
152 	GEM_BUG_ON(intel_context_is_pinned(ce));
153 
154 	if (test_bit(CONTEXT_ALLOC_BIT, &ce->flags)) {
155 		mock_ring_free(ce->ring);
156 		mock_timeline_unpin(ce->timeline);
157 	}
158 
159 	intel_context_fini(ce);
160 	intel_context_free(ce);
161 }
162 
163 static int mock_context_alloc(struct intel_context *ce)
164 {
165 	int err;
166 
167 	ce->ring = mock_ring(ce->engine);
168 	if (!ce->ring)
169 		return -ENOMEM;
170 
171 	ce->timeline = intel_timeline_create(ce->engine->gt);
172 	if (IS_ERR(ce->timeline)) {
173 		kfree(ce->engine);
174 		return PTR_ERR(ce->timeline);
175 	}
176 
177 	err = mock_timeline_pin(ce->timeline);
178 	if (err) {
179 		intel_timeline_put(ce->timeline);
180 		ce->timeline = NULL;
181 		return err;
182 	}
183 
184 	return 0;
185 }
186 
187 static int mock_context_pre_pin(struct intel_context *ce,
188 				struct i915_gem_ww_ctx *ww, void **unused)
189 {
190 	return i915_vma_pin_ww(ce->ring->vma, ww, 0, 0, PIN_GLOBAL | PIN_HIGH);
191 }
192 
193 static int mock_context_pin(struct intel_context *ce, void *unused)
194 {
195 	return 0;
196 }
197 
198 static void mock_context_reset(struct intel_context *ce)
199 {
200 }
201 
202 static const struct intel_context_ops mock_context_ops = {
203 	.alloc = mock_context_alloc,
204 
205 	.pre_pin = mock_context_pre_pin,
206 	.pin = mock_context_pin,
207 	.unpin = mock_context_unpin,
208 	.post_unpin = mock_context_post_unpin,
209 
210 	.enter = intel_context_enter_engine,
211 	.exit = intel_context_exit_engine,
212 
213 	.reset = mock_context_reset,
214 	.destroy = mock_context_destroy,
215 };
216 
217 static int mock_request_alloc(struct i915_request *request)
218 {
219 	INIT_LIST_HEAD(&request->mock.link);
220 	request->mock.delay = 0;
221 
222 	return 0;
223 }
224 
225 static int mock_emit_flush(struct i915_request *request,
226 			   unsigned int flags)
227 {
228 	return 0;
229 }
230 
231 static u32 *mock_emit_breadcrumb(struct i915_request *request, u32 *cs)
232 {
233 	return cs;
234 }
235 
236 static void mock_submit_request(struct i915_request *request)
237 {
238 	struct mock_engine *engine =
239 		container_of(request->engine, typeof(*engine), base);
240 	unsigned long flags;
241 
242 	i915_request_submit(request);
243 
244 	spin_lock_irqsave(&engine->hw_lock, flags);
245 	list_add_tail(&request->mock.link, &engine->hw_queue);
246 	if (list_is_first(&request->mock.link, &engine->hw_queue)) {
247 		if (request->mock.delay)
248 			mod_timer(&engine->hw_delay,
249 				  jiffies + request->mock.delay);
250 		else
251 			advance(request);
252 	}
253 	spin_unlock_irqrestore(&engine->hw_lock, flags);
254 }
255 
256 static void mock_add_to_engine(struct i915_request *rq)
257 {
258 	lockdep_assert_held(&rq->engine->sched_engine->lock);
259 	list_move_tail(&rq->sched.link, &rq->engine->sched_engine->requests);
260 }
261 
262 static void mock_remove_from_engine(struct i915_request *rq)
263 {
264 	struct intel_engine_cs *engine, *locked;
265 
266 	/*
267 	 * Virtual engines complicate acquiring the engine timeline lock,
268 	 * as their rq->engine pointer is not stable until under that
269 	 * engine lock. The simple ploy we use is to take the lock then
270 	 * check that the rq still belongs to the newly locked engine.
271 	 */
272 
273 	locked = READ_ONCE(rq->engine);
274 	spin_lock_irq(&locked->sched_engine->lock);
275 	while (unlikely(locked != (engine = READ_ONCE(rq->engine)))) {
276 		spin_unlock(&locked->sched_engine->lock);
277 		spin_lock(&engine->sched_engine->lock);
278 		locked = engine;
279 	}
280 	list_del_init(&rq->sched.link);
281 	spin_unlock_irq(&locked->sched_engine->lock);
282 }
283 
284 static void mock_reset_prepare(struct intel_engine_cs *engine)
285 {
286 }
287 
288 static void mock_reset_rewind(struct intel_engine_cs *engine, bool stalled)
289 {
290 	GEM_BUG_ON(stalled);
291 }
292 
293 static void mock_reset_cancel(struct intel_engine_cs *engine)
294 {
295 	struct mock_engine *mock =
296 		container_of(engine, typeof(*mock), base);
297 	struct i915_request *rq;
298 	unsigned long flags;
299 
300 	del_timer_sync(&mock->hw_delay);
301 
302 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
303 
304 	/* Mark all submitted requests as skipped. */
305 	list_for_each_entry(rq, &engine->sched_engine->requests, sched.link)
306 		i915_request_put(i915_request_mark_eio(rq));
307 	intel_engine_signal_breadcrumbs(engine);
308 
309 	/* Cancel and submit all pending requests. */
310 	list_for_each_entry(rq, &mock->hw_queue, mock.link) {
311 		if (i915_request_mark_eio(rq)) {
312 			__i915_request_submit(rq);
313 			i915_request_put(rq);
314 		}
315 	}
316 	INIT_LIST_HEAD(&mock->hw_queue);
317 
318 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
319 }
320 
321 static void mock_reset_finish(struct intel_engine_cs *engine)
322 {
323 }
324 
325 static void mock_engine_release(struct intel_engine_cs *engine)
326 {
327 	struct mock_engine *mock =
328 		container_of(engine, typeof(*mock), base);
329 
330 	GEM_BUG_ON(timer_pending(&mock->hw_delay));
331 
332 	i915_sched_engine_put(engine->sched_engine);
333 	intel_breadcrumbs_put(engine->breadcrumbs);
334 
335 	intel_context_unpin(engine->kernel_context);
336 	intel_context_put(engine->kernel_context);
337 
338 	intel_engine_fini_retire(engine);
339 }
340 
341 struct intel_engine_cs *mock_engine(struct drm_i915_private *i915,
342 				    const char *name,
343 				    int id)
344 {
345 	struct mock_engine *engine;
346 
347 	GEM_BUG_ON(id >= I915_NUM_ENGINES);
348 	GEM_BUG_ON(!to_gt(i915)->uncore);
349 
350 	engine = kzalloc(sizeof(*engine) + PAGE_SIZE, GFP_KERNEL);
351 	if (!engine)
352 		return NULL;
353 
354 	/* minimal engine setup for requests */
355 	engine->base.i915 = i915;
356 	engine->base.gt = to_gt(i915);
357 	engine->base.uncore = to_gt(i915)->uncore;
358 	snprintf(engine->base.name, sizeof(engine->base.name), "%s", name);
359 	engine->base.id = id;
360 	engine->base.mask = BIT(id);
361 	engine->base.legacy_idx = INVALID_ENGINE;
362 	engine->base.instance = id;
363 	engine->base.status_page.addr = (void *)(engine + 1);
364 
365 	engine->base.cops = &mock_context_ops;
366 	engine->base.request_alloc = mock_request_alloc;
367 	engine->base.emit_flush = mock_emit_flush;
368 	engine->base.emit_fini_breadcrumb = mock_emit_breadcrumb;
369 	engine->base.submit_request = mock_submit_request;
370 	engine->base.add_active_request = mock_add_to_engine;
371 	engine->base.remove_active_request = mock_remove_from_engine;
372 
373 	engine->base.reset.prepare = mock_reset_prepare;
374 	engine->base.reset.rewind = mock_reset_rewind;
375 	engine->base.reset.cancel = mock_reset_cancel;
376 	engine->base.reset.finish = mock_reset_finish;
377 
378 	engine->base.release = mock_engine_release;
379 
380 	to_gt(i915)->engine[id] = &engine->base;
381 	to_gt(i915)->engine_class[0][id] = &engine->base;
382 
383 	/* fake hw queue */
384 	spin_lock_init(&engine->hw_lock);
385 	timer_setup(&engine->hw_delay, hw_delay_complete, 0);
386 	INIT_LIST_HEAD(&engine->hw_queue);
387 
388 	intel_engine_add_user(&engine->base);
389 
390 	return &engine->base;
391 }
392 
393 int mock_engine_init(struct intel_engine_cs *engine)
394 {
395 	struct intel_context *ce;
396 
397 	INIT_LIST_HEAD(&engine->pinned_contexts_list);
398 
399 	engine->sched_engine = i915_sched_engine_create(ENGINE_MOCK);
400 	if (!engine->sched_engine)
401 		return -ENOMEM;
402 	engine->sched_engine->private_data = engine;
403 
404 	intel_engine_init_execlists(engine);
405 	intel_engine_init__pm(engine);
406 	intel_engine_init_retire(engine);
407 
408 	engine->breadcrumbs = intel_breadcrumbs_create(NULL);
409 	if (!engine->breadcrumbs)
410 		goto err_schedule;
411 
412 	ce = create_kernel_context(engine);
413 	if (IS_ERR(ce))
414 		goto err_breadcrumbs;
415 
416 	/* We insist the kernel context is using the status_page */
417 	engine->status_page.vma = ce->timeline->hwsp_ggtt;
418 
419 	engine->kernel_context = ce;
420 	return 0;
421 
422 err_breadcrumbs:
423 	intel_breadcrumbs_put(engine->breadcrumbs);
424 err_schedule:
425 	i915_sched_engine_put(engine->sched_engine);
426 	return -ENOMEM;
427 }
428 
429 void mock_engine_flush(struct intel_engine_cs *engine)
430 {
431 	struct mock_engine *mock =
432 		container_of(engine, typeof(*mock), base);
433 	struct i915_request *request, *rn;
434 
435 	del_timer_sync(&mock->hw_delay);
436 
437 	spin_lock_irq(&mock->hw_lock);
438 	list_for_each_entry_safe(request, rn, &mock->hw_queue, mock.link)
439 		advance(request);
440 	spin_unlock_irq(&mock->hw_lock);
441 }
442 
443 void mock_engine_reset(struct intel_engine_cs *engine)
444 {
445 }
446