summaryrefslogtreecommitdiff
path: root/drivers/gpu/drm/i915/gt/intel_gt_requests.c
blob: 1dfd01668c79c638aa525d9f6a224b904bf381f4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
// SPDX-License-Identifier: MIT
/*
 * Copyright © 2019 Intel Corporation
 */

#include <linux/workqueue.h>

#include "i915_drv.h" /* for_each_engine() */
#include "i915_request.h"
#include "intel_engine_heartbeat.h"
#include "intel_execlists_submission.h"
#include "intel_gt.h"
#include "intel_gt_pm.h"
#include "intel_gt_requests.h"
#include "intel_timeline.h"

static bool retire_requests(struct intel_timeline *tl)
{
	struct i915_request *rq, *rn;

	list_for_each_entry_safe(rq, rn, &tl->requests, link)
		if (!i915_request_retire(rq))
			return false;

	/* And check nothing new was submitted */
	return !i915_active_fence_isset(&tl->last_request);
}

static bool engine_active(const struct intel_engine_cs *engine)
{
	return !list_empty(&engine->kernel_context->timeline->requests);
}

static bool flush_submission(struct intel_gt *gt, long timeout)
{
	struct intel_engine_cs *engine;
	enum intel_engine_id id;
	bool active = false;

	if (!timeout)
		return false;

	if (!intel_gt_pm_is_awake(gt))
		return false;

	for_each_engine(engine, gt, id) {
		intel_engine_flush_submission(engine);

		/* Flush the background retirement and idle barriers */
		flush_work(&engine->retire_work);
		flush_delayed_work(&engine->wakeref.work);

		/* Is the idle barrier still outstanding? */
		active |= engine_active(engine);
	}

	return active;
}

static void engine_retire(struct work_struct *work)
{
	struct intel_engine_cs *engine =
		container_of(work, typeof(*engine), retire_work);
	struct intel_timeline *tl = xchg(&engine->retire, NULL);

	do {
		struct intel_timeline *next = xchg(&tl->retire, NULL);

		/*
		 * Our goal here is to retire _idle_ timelines as soon as
		 * possible (as they are idle, we do not expect userspace
		 * to be cleaning up anytime soon).
		 *
		 * If the timeline is currently locked, either it is being
		 * retired elsewhere or about to be!
		 */
		if (mutex_trylock(&tl->mutex)) {
			retire_requests(tl);
			mutex_unlock(&tl->mutex);
		}
		intel_timeline_put(tl);

		GEM_BUG_ON(!next);
		tl = ptr_mask_bits(next, 1);
	} while (tl);
}

static bool add_retire(struct intel_engine_cs *engine,
		       struct intel_timeline *tl)
{
#define STUB ((struct intel_timeline *)1)
	struct intel_timeline *first;

	/*
	 * We open-code a llist here to include the additional tag [BIT(0)]
	 * so that we know when the timeline is already on a
	 * retirement queue: either this engine or another.
	 */

	if (cmpxchg(&tl->retire, NULL, STUB)) /* already queued */
		return false;

	intel_timeline_get(tl);
	first = READ_ONCE(engine->retire);
	do
		tl->retire = ptr_pack_bits(first, 1, 1);
	while (!try_cmpxchg(&engine->retire, &first, tl));

	return !first;
}

void intel_engine_add_retire(struct intel_engine_cs *engine,
			     struct intel_timeline *tl)
{
	/* We don't deal well with the engine disappearing beneath us */
	GEM_BUG_ON(intel_engine_is_virtual(engine));

	if (add_retire(engine, tl))
		schedule_work(&engine->retire_work);
}

void intel_engine_init_retire(struct intel_engine_cs *engine)
{
	INIT_WORK(&engine->retire_work, engine_retire);
}

void intel_engine_fini_retire(struct intel_engine_cs *engine)
{
	flush_work(&engine->retire_work);
	GEM_BUG_ON(engine->retire);
}

long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout,
				      long *remaining_timeout)
{
	struct intel_gt_timelines *timelines = &gt->timelines;
	struct intel_timeline *tl, *tn;
	unsigned long active_count = 0;
	LIST_HEAD(free);

	flush_submission(gt, timeout); /* kick the ksoftirqd tasklets */
	spin_lock(&timelines->lock);
	list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
		if (!mutex_trylock(&tl->mutex)) {
			active_count++; /* report busy to caller, try again? */
			continue;
		}

		intel_timeline_get(tl);
		GEM_BUG_ON(!atomic_read(&tl->active_count));
		atomic_inc(&tl->active_count); /* pin the list element */
		spin_unlock(&timelines->lock);

		if (timeout > 0) {
			struct dma_fence *fence;

			fence = i915_active_fence_get(&tl->last_request);
			if (fence) {
				mutex_unlock(&tl->mutex);

				timeout = dma_fence_wait_timeout(fence,
								 true,
								 timeout);
				dma_fence_put(fence);

				/* Retirement is best effort */
				if (!mutex_trylock(&tl->mutex)) {
					active_count++;
					goto out_active;
				}
			}
		}

		if (!retire_requests(tl))
			active_count++;
		mutex_unlock(&tl->mutex);

out_active:	spin_lock(&timelines->lock);

		/* Resume list iteration after reacquiring spinlock */
		list_safe_reset_next(tl, tn, link);
		if (atomic_dec_and_test(&tl->active_count))
			list_del(&tl->link);

		/* Defer the final release to after the spinlock */
		if (refcount_dec_and_test(&tl->kref.refcount)) {
			GEM_BUG_ON(atomic_read(&tl->active_count));
			list_add(&tl->link, &free);
		}
	}
	spin_unlock(&timelines->lock);

	list_for_each_entry_safe(tl, tn, &free, link)
		__intel_timeline_free(&tl->kref);

	if (flush_submission(gt, timeout)) /* Wait, there's more! */
		active_count++;

	if (remaining_timeout)
		*remaining_timeout = timeout;

	return active_count ? timeout ?: -ETIME : 0;
}

static void retire_work_handler(struct work_struct *work)
{
	struct intel_gt *gt =
		container_of(work, typeof(*gt), requests.retire_work.work);

	schedule_delayed_work(&gt->requests.retire_work,
			      round_jiffies_up_relative(HZ));
	intel_gt_retire_requests(gt);
}

void intel_gt_init_requests(struct intel_gt *gt)
{
	INIT_DELAYED_WORK(&gt->requests.retire_work, retire_work_handler);
}

void intel_gt_park_requests(struct intel_gt *gt)
{
	cancel_delayed_work(&gt->requests.retire_work);
}

void intel_gt_unpark_requests(struct intel_gt *gt)
{
	schedule_delayed_work(&gt->requests.retire_work,
			      round_jiffies_up_relative(HZ));
}

void intel_gt_fini_requests(struct intel_gt *gt)
{
	/* Wait until the work is marked as finished before unloading! */
	cancel_delayed_work_sync(&gt->requests.retire_work);

	flush_work(&gt->watchdog.work);
}

void intel_gt_watchdog_work(struct work_struct *work)
{
	struct intel_gt *gt =
		container_of(work, typeof(*gt), watchdog.work);
	struct i915_request *rq, *rn;
	struct llist_node *first;

	first = llist_del_all(&gt->watchdog.list);
	if (!first)
		return;

	llist_for_each_entry_safe(rq, rn, first, watchdog.link) {
		if (!i915_request_completed(rq)) {
			struct dma_fence *f = &rq->fence;

			pr_notice("Fence expiration time out i915-%s:%s:%llx!\n",
				  f->ops->get_driver_name(f),
				  f->ops->get_timeline_name(f),
				  f->seqno);
			i915_request_cancel(rq, -EINTR);
		}
		i915_request_put(rq);
	}
}