selftest_context.c

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Copyright © 2019 Intel Corporation
  4 */
  5
  6#include <drm/drm_print.h>
  7
  8#include "i915_selftest.h"
  9#include "intel_engine_heartbeat.h"
 10#include "intel_engine_pm.h"
 11#include "intel_gt.h"
 12
 13#include "gem/selftests/mock_context.h"
 14#include "selftests/igt_flush_test.h"
 15#include "selftests/mock_drm.h"
 16
 17static int request_sync(struct i915_request *rq)
 18{
 19	struct intel_timeline *tl = i915_request_timeline(rq);
 20	long timeout;
 21	int err = 0;
 22
 23	intel_timeline_get(tl);
 24	i915_request_get(rq);
 25
 26	/* Opencode i915_request_add() so we can keep the timeline locked. */
 27	__i915_request_commit(rq);
 28	rq->sched.attr.priority = I915_PRIORITY_BARRIER;
 29	__i915_request_queue_bh(rq);
 30
 31	timeout = i915_request_wait(rq, 0, HZ / 10);
 32	if (timeout < 0)
 33		err = timeout;
 34	else
 35		i915_request_retire_upto(rq);
 36
 37	lockdep_unpin_lock(&tl->mutex, rq->cookie);
 38	mutex_unlock(&tl->mutex);
 39
 40	i915_request_put(rq);
 41	intel_timeline_put(tl);
 42
 43	return err;
 44}
 45
 46static int context_sync(struct intel_context *ce)
 47{
 48	struct intel_timeline *tl = ce->timeline;
 49	int err = 0;
 50
 51	mutex_lock(&tl->mutex);
 52	do {
 53		struct i915_request *rq;
 54		long timeout;
 55
 56		if (list_empty(&tl->requests))
 57			break;
 58
 59		rq = list_last_entry(&tl->requests, typeof(*rq), link);
 60		i915_request_get(rq);
 61
 62		timeout = i915_request_wait(rq, 0, HZ / 10);
 63		if (timeout < 0)
 64			err = timeout;
 65		else
 66			i915_request_retire_upto(rq);
 67
 68		i915_request_put(rq);
 69	} while (!err);
 70	mutex_unlock(&tl->mutex);
 71
 72	/* Wait for all barriers to complete (remote CPU) before we check */
 73	i915_active_unlock_wait(&ce->active);
 74	return err;
 75}
 76
 77static int __live_context_size(struct intel_engine_cs *engine)
 78{
 79	struct intel_context *ce;
 80	struct i915_request *rq;
 81	void *vaddr;
 82	int err;
 83
 84	ce = intel_context_create(engine);
 85	if (IS_ERR(ce))
 86		return PTR_ERR(ce);
 87
 88	err = intel_context_pin(ce);
 89	if (err)
 90		goto err;
 91
 92	vaddr = i915_gem_object_pin_map_unlocked(ce->state->obj,
 93						 intel_gt_coherent_map_type(engine->gt,
 94									    ce->state->obj,
 95									    false));
 96	if (IS_ERR(vaddr)) {
 97		err = PTR_ERR(vaddr);
 98		intel_context_unpin(ce);
 99		goto err;
100	}
101
102	/*
103	 * Note that execlists also applies a redzone which it checks on
104	 * context unpin when debugging. We are using the same location
105	 * and same poison value so that our checks overlap. Despite the
106	 * redundancy, we want to keep this little selftest so that we
107	 * get coverage of any and all submission backends, and we can
108	 * always extend this test to ensure we trick the HW into a
109	 * compromising position wrt to the various sections that need
110	 * to be written into the context state.
111	 *
112	 * TLDR; this overlaps with the execlists redzone.
113	 */
114	vaddr += engine->context_size - I915_GTT_PAGE_SIZE;
115	memset(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE);
116
117	rq = intel_context_create_request(ce);
118	intel_context_unpin(ce);
119	if (IS_ERR(rq)) {
120		err = PTR_ERR(rq);
121		goto err_unpin;
122	}
123
124	err = request_sync(rq);
125	if (err)
126		goto err_unpin;
127
128	/* Force the context switch */
129	rq = intel_engine_create_kernel_request(engine);
130	if (IS_ERR(rq)) {
131		err = PTR_ERR(rq);
132		goto err_unpin;
133	}
134	err = request_sync(rq);
135	if (err)
136		goto err_unpin;
137
138	if (memchr_inv(vaddr, POISON_INUSE, I915_GTT_PAGE_SIZE)) {
139		pr_err("%s context overwrote trailing red-zone!", engine->name);
140		err = -EINVAL;
141	}
142
143err_unpin:
144	i915_gem_object_unpin_map(ce->state->obj);
145err:
146	intel_context_put(ce);
147	return err;
148}
149
150static int live_context_size(void *arg)
151{
152	struct intel_gt *gt = arg;
153	struct intel_engine_cs *engine;
154	enum intel_engine_id id;
155	int err = 0;
156
157	/*
158	 * Check that our context sizes are correct by seeing if the
159	 * HW tries to write past the end of one.
160	 */
161
162	for_each_engine(engine, gt, id) {
163		struct file *saved;
164
165		if (!engine->context_size)
166			continue;
167
168		intel_engine_pm_get(engine);
169
170		/*
171		 * Hide the old default state -- we lie about the context size
172		 * and get confused when the default state is smaller than
173		 * expected. For our do nothing request, inheriting the
174		 * active state is sufficient, we are only checking that we
175		 * don't use more than we planned.
176		 */
177		saved = fetch_and_zero(&engine->default_state);
178
179		/* Overlaps with the execlists redzone */
180		engine->context_size += I915_GTT_PAGE_SIZE;
181
182		err = __live_context_size(engine);
183
184		engine->context_size -= I915_GTT_PAGE_SIZE;
185
186		engine->default_state = saved;
187
188		intel_engine_pm_put(engine);
189
190		if (err)
191			break;
192	}
193
194	return err;
195}
196
197static int __live_active_context(struct intel_engine_cs *engine)
198{
199	unsigned long saved_heartbeat;
200	struct intel_context *ce;
201	int pass;
202	int err;
203
204	/*
205	 * We keep active contexts alive until after a subsequent context
206	 * switch as the final write from the context-save will be after
207	 * we retire the final request. We track when we unpin the context,
208	 * under the presumption that the final pin is from the last request,
209	 * and instead of immediately unpinning the context, we add a task
210	 * to unpin the context from the next idle-barrier.
211	 *
212	 * This test makes sure that the context is kept alive until a
213	 * subsequent idle-barrier (emitted when the engine wakeref hits 0
214	 * with no more outstanding requests).
215	 *
216	 * In GuC submission mode we don't use idle barriers and we instead
217	 * get a message from the GuC to signal that it is safe to unpin the
218	 * context from memory.
219	 */
220	if (intel_engine_uses_guc(engine))
221		return 0;
222
223	if (intel_engine_pm_is_awake(engine)) {
224		pr_err("%s is awake before starting %s!\n",
225		       engine->name, __func__);
226		return -EINVAL;
227	}
228
229	ce = intel_context_create(engine);
230	if (IS_ERR(ce))
231		return PTR_ERR(ce);
232
233	saved_heartbeat = engine->props.heartbeat_interval_ms;
234	engine->props.heartbeat_interval_ms = 0;
235
236	for (pass = 0; pass <= 2; pass++) {
237		struct i915_request *rq;
238
239		intel_engine_pm_get(engine);
240
241		rq = intel_context_create_request(ce);
242		if (IS_ERR(rq)) {
243			err = PTR_ERR(rq);
244			goto out_engine;
245		}
246
247		err = request_sync(rq);
248		if (err)
249			goto out_engine;
250
251		/* Context will be kept active until after an idle-barrier. */
252		if (i915_active_is_idle(&ce->active)) {
253			pr_err("context is not active; expected idle-barrier (%s pass %d)\n",
254			       engine->name, pass);
255			err = -EINVAL;
256			goto out_engine;
257		}
258
259		if (!intel_engine_pm_is_awake(engine)) {
260			pr_err("%s is asleep before idle-barrier\n",
261			       engine->name);
262			err = -EINVAL;
263			goto out_engine;
264		}
265
266out_engine:
267		intel_engine_pm_put(engine);
268		if (err)
269			goto err;
270	}
271
272	/* Now make sure our idle-barriers are flushed */
273	err = intel_engine_flush_barriers(engine);
274	if (err)
275		goto err;
276
277	/* Wait for the barrier and in the process wait for engine to park */
278	err = context_sync(engine->kernel_context);
279	if (err)
280		goto err;
281
282	if (!i915_active_is_idle(&ce->active)) {
283		pr_err("context is still active!");
284		err = -EINVAL;
285	}
286
287	intel_engine_pm_flush(engine);
288
289	if (intel_engine_pm_is_awake(engine)) {
290		struct drm_printer p = drm_dbg_printer(&engine->i915->drm,
291						       DRM_UT_DRIVER, NULL);
292
293		intel_engine_dump(engine, &p,
294				  "%s is still awake:%d after idle-barriers\n",
295				  engine->name,
296				  atomic_read(&engine->wakeref.count));
297		GEM_TRACE_DUMP();
298
299		err = -EINVAL;
300		goto err;
301	}
302
303err:
304	engine->props.heartbeat_interval_ms = saved_heartbeat;
305	intel_context_put(ce);
306	return err;
307}
308
309static int live_active_context(void *arg)
310{
311	struct intel_gt *gt = arg;
312	struct intel_engine_cs *engine;
313	enum intel_engine_id id;
314	int err = 0;
315
316	for_each_engine(engine, gt, id) {
317		err = __live_active_context(engine);
318		if (err)
319			break;
320
321		err = igt_flush_test(gt->i915);
322		if (err)
323			break;
324	}
325
326	return err;
327}
328
329static int __remote_sync(struct intel_context *ce, struct intel_context *remote)
330{
331	struct i915_request *rq;
332	int err;
333
334	err = intel_context_pin(remote);
335	if (err)
336		return err;
337
338	rq = intel_context_create_request(ce);
339	if (IS_ERR(rq)) {
340		err = PTR_ERR(rq);
341		goto unpin;
342	}
343
344	err = intel_context_prepare_remote_request(remote, rq);
345	if (err) {
346		i915_request_add(rq);
347		goto unpin;
348	}
349
350	err = request_sync(rq);
351
352unpin:
353	intel_context_unpin(remote);
354	return err;
355}
356
357static int __live_remote_context(struct intel_engine_cs *engine)
358{
359	struct intel_context *local, *remote;
360	unsigned long saved_heartbeat;
361	int pass;
362	int err;
363
364	/*
365	 * Check that our idle barriers do not interfere with normal
366	 * activity tracking. In particular, check that operating
367	 * on the context image remotely (intel_context_prepare_remote_request),
368	 * which inserts foreign fences into intel_context.active, does not
369	 * clobber the idle-barrier.
370	 *
371	 * In GuC submission mode we don't use idle barriers.
372	 */
373	if (intel_engine_uses_guc(engine))
374		return 0;
375
376	if (intel_engine_pm_is_awake(engine)) {
377		pr_err("%s is awake before starting %s!\n",
378		       engine->name, __func__);
379		return -EINVAL;
380	}
381
382	remote = intel_context_create(engine);
383	if (IS_ERR(remote))
384		return PTR_ERR(remote);
385
386	local = intel_context_create(engine);
387	if (IS_ERR(local)) {
388		err = PTR_ERR(local);
389		goto err_remote;
390	}
391
392	saved_heartbeat = engine->props.heartbeat_interval_ms;
393	engine->props.heartbeat_interval_ms = 0;
394	intel_engine_pm_get(engine);
395
396	for (pass = 0; pass <= 2; pass++) {
397		err = __remote_sync(local, remote);
398		if (err)
399			break;
400
401		err = __remote_sync(engine->kernel_context, remote);
402		if (err)
403			break;
404
405		if (i915_active_is_idle(&remote->active)) {
406			pr_err("remote context is not active; expected idle-barrier (%s pass %d)\n",
407			       engine->name, pass);
408			err = -EINVAL;
409			break;
410		}
411	}
412
413	intel_engine_pm_put(engine);
414	engine->props.heartbeat_interval_ms = saved_heartbeat;
415
416	intel_context_put(local);
417err_remote:
418	intel_context_put(remote);
419	return err;
420}
421
422static int live_remote_context(void *arg)
423{
424	struct intel_gt *gt = arg;
425	struct intel_engine_cs *engine;
426	enum intel_engine_id id;
427	int err = 0;
428
429	for_each_engine(engine, gt, id) {
430		err = __live_remote_context(engine);
431		if (err)
432			break;
433
434		err = igt_flush_test(gt->i915);
435		if (err)
436			break;
437	}
438
439	return err;
440}
441
442int intel_context_live_selftests(struct drm_i915_private *i915)
443{
444	static const struct i915_subtest tests[] = {
445		SUBTEST(live_context_size),
446		SUBTEST(live_active_context),
447		SUBTEST(live_remote_context),
448	};
449	struct intel_gt *gt = to_gt(i915);
450
451	if (intel_gt_is_wedged(gt))
452		return 0;
453
454	return intel_gt_live_subtests(tests, gt);
455}