1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright © 2019 Intel Corporation
4  */
5 
6 #include "i915_selftest.h"
7 #include "intel_engine_heartbeat.h"
8 #include "intel_engine_pm.h"
9 #include "intel_gt.h"
10 
11 #include "gem/selftests/mock_context.h"
12 #include "selftests/igt_flush_test.h"
13 #include "selftests/mock_drm.h"
14 
15 static int request_sync(struct i915_request *rq)
16 {
17 	struct intel_timeline *tl = i915_request_timeline(rq);
18 	long timeout;
19 	int err = 0;
20 
21 	intel_timeline_get(tl);
22 	i915_request_get(rq);
23 
24 	/* Opencode i915_request_add() so we can keep the timeline locked. */
25 	__i915_request_commit(rq);
26 	rq->sched.attr.priority = I915_PRIORITY_BARRIER;
27 	__i915_request_queue_bh(rq);
28 
29 	timeout = i915_request_wait(rq, 0, HZ / 10);
30 	if (timeout < 0)
31 		err = timeout;
32 	else
33 		i915_request_retire_upto(rq);
34 
35 	lockdep_unpin_lock(&tl->mutex, rq->cookie);
36 	mutex_unlock(&tl->mutex);
37 
38 	i915_request_put(rq);
39 	intel_timeline_put(tl);
40 
41 	return err;
42 }
43 
44 static int context_sync(struct intel_context *ce)
45 {
46 	struct intel_timeline *tl = ce->timeline;
47 	int err = 0;
48 
49 	mutex_lock(&tl->mutex);
50 	do {
51 		struct i915_request *rq;
52 		long timeout;
53 
54 		if (list_empty(&tl->requests))
55 			break;
56 
57 		rq = list_last_entry(&tl->requests, typeof(*rq), link);
58 		i915_request_get(rq);
59 
60 		timeout = i915_request_wait(rq, 0, HZ / 10);
61 		if (timeout < 0)
62 			err = timeout;
63 		else
64 			i915_request_retire_upto(rq);
65 
66 		i915_request_put(rq);
67 	} while (!err);
68 	mutex_unlock(&tl->mutex);
69 
70 	/* Wait for all barriers to complete (remote CPU) before we check */
71 	i915_active_unlock_wait(&ce->active);
72 	return err;
73 }
74 
75 static int __live_context_size(struct intel_engine_cs *engine)
76 {
77 	struct intel_context *ce;
78 	struct i915_request *rq;
79 	void *vaddr;
80 	int err;
81 
82 	ce = intel_context_create(engine);
83 	if (IS_ERR(ce))
84 		return PTR_ERR(ce);
85 
86 	err = intel_context_pin(ce);
87 	if (err)
88 		goto err;
89 
90 	vaddr = i915_gem_object_pin_map_unlocked(ce->state->obj,
91 						 i915_coherent_map_type(engine->i915,
92 									ce->state->obj, false));
93 	if (IS_ERR(vaddr)) {
94 		err = PTR_ERR(vaddr);
95 		intel_context_unpin(ce);
96 		goto err;
97 	}
98 
99 	/*
100 	 * Note that execlists also applies a redzone which it checks on
101 	 * context unpin when debugging. We are using the same location
102 	 * and same poison value so that our checks overlap. Despite the
103 	 * redundancy, we want to keep this little selftest so that we
104 	 * get coverage of any and all submission backends, and we can
105 	 * always extend this test to ensure we trick the HW into a
106 	 * compromising position wrt to the various sections that need
107 	 * to be written into the context state.
108 	 *
109 	 * TLDR; this overlaps with the execlists redzone.
110 	 */
111 	vaddr += engine->context_size - I915_GTT_PAGE_SIZE;
112 	memset(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE);
113 
114 	rq = intel_context_create_request(ce);
115 	intel_context_unpin(ce);
116 	if (IS_ERR(rq)) {
117 		err = PTR_ERR(rq);
118 		goto err_unpin;
119 	}
120 
121 	err = request_sync(rq);
122 	if (err)
123 		goto err_unpin;
124 
125 	/* Force the context switch */
126 	rq = intel_engine_create_kernel_request(engine);
127 	if (IS_ERR(rq)) {
128 		err = PTR_ERR(rq);
129 		goto err_unpin;
130 	}
131 	err = request_sync(rq);
132 	if (err)
133 		goto err_unpin;
134 
135 	if (memchr_inv(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE)) {
136 		pr_err("%s context overwrote trailing red-zone!", engine->name);
137 		err = -EINVAL;
138 	}
139 
140 err_unpin:
141 	i915_gem_object_unpin_map(ce->state->obj);
142 err:
143 	intel_context_put(ce);
144 	return err;
145 }
146 
147 static int live_context_size(void *arg)
148 {
149 	struct intel_gt *gt = arg;
150 	struct intel_engine_cs *engine;
151 	enum intel_engine_id id;
152 	int err = 0;
153 
154 	/*
155 	 * Check that our context sizes are correct by seeing if the
156 	 * HW tries to write past the end of one.
157 	 */
158 
159 	for_each_engine(engine, gt, id) {
160 		struct file *saved;
161 
162 		if (!engine->context_size)
163 			continue;
164 
165 		intel_engine_pm_get(engine);
166 
167 		/*
168 		 * Hide the old default state -- we lie about the context size
169 		 * and get confused when the default state is smaller than
170 		 * expected. For our do nothing request, inheriting the
171 		 * active state is sufficient, we are only checking that we
172 		 * don't use more than we planned.
173 		 */
174 		saved = fetch_and_zero(&engine->default_state);
175 
176 		/* Overlaps with the execlists redzone */
177 		engine->context_size += I915_GTT_PAGE_SIZE;
178 
179 		err = __live_context_size(engine);
180 
181 		engine->context_size -= I915_GTT_PAGE_SIZE;
182 
183 		engine->default_state = saved;
184 
185 		intel_engine_pm_put(engine);
186 
187 		if (err)
188 			break;
189 	}
190 
191 	return err;
192 }
193 
194 static int __live_active_context(struct intel_engine_cs *engine)
195 {
196 	unsigned long saved_heartbeat;
197 	struct intel_context *ce;
198 	int pass;
199 	int err;
200 
201 	/*
202 	 * We keep active contexts alive until after a subsequent context
203 	 * switch as the final write from the context-save will be after
204 	 * we retire the final request. We track when we unpin the context,
205 	 * under the presumption that the final pin is from the last request,
206 	 * and instead of immediately unpinning the context, we add a task
207 	 * to unpin the context from the next idle-barrier.
208 	 *
209 	 * This test makes sure that the context is kept alive until a
210 	 * subsequent idle-barrier (emitted when the engine wakeref hits 0
211 	 * with no more outstanding requests).
212 	 *
213 	 * In GuC submission mode we don't use idle barriers and we instead
214 	 * get a message from the GuC to signal that it is safe to unpin the
215 	 * context from memory.
216 	 */
217 	if (intel_engine_uses_guc(engine))
218 		return 0;
219 
220 	if (intel_engine_pm_is_awake(engine)) {
221 		pr_err("%s is awake before starting %s!\n",
222 		       engine->name, __func__);
223 		return -EINVAL;
224 	}
225 
226 	ce = intel_context_create(engine);
227 	if (IS_ERR(ce))
228 		return PTR_ERR(ce);
229 
230 	saved_heartbeat = engine->props.heartbeat_interval_ms;
231 	engine->props.heartbeat_interval_ms = 0;
232 
233 	for (pass = 0; pass <= 2; pass++) {
234 		struct i915_request *rq;
235 
236 		intel_engine_pm_get(engine);
237 
238 		rq = intel_context_create_request(ce);
239 		if (IS_ERR(rq)) {
240 			err = PTR_ERR(rq);
241 			goto out_engine;
242 		}
243 
244 		err = request_sync(rq);
245 		if (err)
246 			goto out_engine;
247 
248 		/* Context will be kept active until after an idle-barrier. */
249 		if (i915_active_is_idle(&ce->active)) {
250 			pr_err("context is not active; expected idle-barrier (%s pass %d)\n",
251 			       engine->name, pass);
252 			err = -EINVAL;
253 			goto out_engine;
254 		}
255 
256 		if (!intel_engine_pm_is_awake(engine)) {
257 			pr_err("%s is asleep before idle-barrier\n",
258 			       engine->name);
259 			err = -EINVAL;
260 			goto out_engine;
261 		}
262 
263 out_engine:
264 		intel_engine_pm_put(engine);
265 		if (err)
266 			goto err;
267 	}
268 
269 	/* Now make sure our idle-barriers are flushed */
270 	err = intel_engine_flush_barriers(engine);
271 	if (err)
272 		goto err;
273 
274 	/* Wait for the barrier and in the process wait for engine to park */
275 	err = context_sync(engine->kernel_context);
276 	if (err)
277 		goto err;
278 
279 	if (!i915_active_is_idle(&ce->active)) {
280 		pr_err("context is still active!");
281 		err = -EINVAL;
282 	}
283 
284 	intel_engine_pm_flush(engine);
285 
286 	if (intel_engine_pm_is_awake(engine)) {
287 		struct drm_printer p = drm_debug_printer(__func__);
288 
289 		intel_engine_dump(engine, &p,
290 				  "%s is still awake:%d after idle-barriers\n",
291 				  engine->name,
292 				  atomic_read(&engine->wakeref.count));
293 		GEM_TRACE_DUMP();
294 
295 		err = -EINVAL;
296 		goto err;
297 	}
298 
299 err:
300 	engine->props.heartbeat_interval_ms = saved_heartbeat;
301 	intel_context_put(ce);
302 	return err;
303 }
304 
305 static int live_active_context(void *arg)
306 {
307 	struct intel_gt *gt = arg;
308 	struct intel_engine_cs *engine;
309 	enum intel_engine_id id;
310 	int err = 0;
311 
312 	for_each_engine(engine, gt, id) {
313 		err = __live_active_context(engine);
314 		if (err)
315 			break;
316 
317 		err = igt_flush_test(gt->i915);
318 		if (err)
319 			break;
320 	}
321 
322 	return err;
323 }
324 
325 static int __remote_sync(struct intel_context *ce, struct intel_context *remote)
326 {
327 	struct i915_request *rq;
328 	int err;
329 
330 	err = intel_context_pin(remote);
331 	if (err)
332 		return err;
333 
334 	rq = intel_context_create_request(ce);
335 	if (IS_ERR(rq)) {
336 		err = PTR_ERR(rq);
337 		goto unpin;
338 	}
339 
340 	err = intel_context_prepare_remote_request(remote, rq);
341 	if (err) {
342 		i915_request_add(rq);
343 		goto unpin;
344 	}
345 
346 	err = request_sync(rq);
347 
348 unpin:
349 	intel_context_unpin(remote);
350 	return err;
351 }
352 
353 static int __live_remote_context(struct intel_engine_cs *engine)
354 {
355 	struct intel_context *local, *remote;
356 	unsigned long saved_heartbeat;
357 	int pass;
358 	int err;
359 
360 	/*
361 	 * Check that our idle barriers do not interfere with normal
362 	 * activity tracking. In particular, check that operating
363 	 * on the context image remotely (intel_context_prepare_remote_request),
364 	 * which inserts foreign fences into intel_context.active, does not
365 	 * clobber the idle-barrier.
366 	 *
367 	 * In GuC submission mode we don't use idle barriers.
368 	 */
369 	if (intel_engine_uses_guc(engine))
370 		return 0;
371 
372 	if (intel_engine_pm_is_awake(engine)) {
373 		pr_err("%s is awake before starting %s!\n",
374 		       engine->name, __func__);
375 		return -EINVAL;
376 	}
377 
378 	remote = intel_context_create(engine);
379 	if (IS_ERR(remote))
380 		return PTR_ERR(remote);
381 
382 	local = intel_context_create(engine);
383 	if (IS_ERR(local)) {
384 		err = PTR_ERR(local);
385 		goto err_remote;
386 	}
387 
388 	saved_heartbeat = engine->props.heartbeat_interval_ms;
389 	engine->props.heartbeat_interval_ms = 0;
390 	intel_engine_pm_get(engine);
391 
392 	for (pass = 0; pass <= 2; pass++) {
393 		err = __remote_sync(local, remote);
394 		if (err)
395 			break;
396 
397 		err = __remote_sync(engine->kernel_context, remote);
398 		if (err)
399 			break;
400 
401 		if (i915_active_is_idle(&remote->active)) {
402 			pr_err("remote context is not active; expected idle-barrier (%s pass %d)\n",
403 			       engine->name, pass);
404 			err = -EINVAL;
405 			break;
406 		}
407 	}
408 
409 	intel_engine_pm_put(engine);
410 	engine->props.heartbeat_interval_ms = saved_heartbeat;
411 
412 	intel_context_put(local);
413 err_remote:
414 	intel_context_put(remote);
415 	return err;
416 }
417 
418 static int live_remote_context(void *arg)
419 {
420 	struct intel_gt *gt = arg;
421 	struct intel_engine_cs *engine;
422 	enum intel_engine_id id;
423 	int err = 0;
424 
425 	for_each_engine(engine, gt, id) {
426 		err = __live_remote_context(engine);
427 		if (err)
428 			break;
429 
430 		err = igt_flush_test(gt->i915);
431 		if (err)
432 			break;
433 	}
434 
435 	return err;
436 }
437 
438 int intel_context_live_selftests(struct drm_i915_private *i915)
439 {
440 	static const struct i915_subtest tests[] = {
441 		SUBTEST(live_context_size),
442 		SUBTEST(live_active_context),
443 		SUBTEST(live_remote_context),
444 	};
445 	struct intel_gt *gt = to_gt(i915);
446 
447 	if (intel_gt_is_wedged(gt))
448 		return 0;
449 
450 	return intel_gt_live_subtests(tests, gt);
451 }
452