2 * SPDX-License-Identifier: MIT
4 * Copyright © 2019 Intel Corporation
7 #include <linux/workqueue.h>
9 #include "i915_drv.h" /* for_each_engine() */
10 #include "i915_request.h"
11 #include "intel_engine_heartbeat.h"
13 #include "intel_gt_pm.h"
14 #include "intel_gt_requests.h"
15 #include "intel_timeline.h"
17 static bool retire_requests(struct intel_timeline *tl)
19 struct i915_request *rq, *rn;
21 list_for_each_entry_safe(rq, rn, &tl->requests, link)
22 if (!i915_request_retire(rq))
25 /* And check nothing new was submitted */
26 return !i915_active_fence_isset(&tl->last_request);
29 static bool flush_submission(struct intel_gt *gt)
31 struct intel_engine_cs *engine;
32 enum intel_engine_id id;
35 if (!intel_gt_pm_is_awake(gt))
38 for_each_engine(engine, gt, id) {
39 intel_engine_flush_submission(engine);
40 active |= flush_work(&engine->retire_work);
41 active |= flush_work(&engine->wakeref.work);
47 static void engine_retire(struct work_struct *work)
49 struct intel_engine_cs *engine =
50 container_of(work, typeof(*engine), retire_work);
51 struct intel_timeline *tl = xchg(&engine->retire, NULL);
54 struct intel_timeline *next = xchg(&tl->retire, NULL);
57 * Our goal here is to retire _idle_ timelines as soon as
58 * possible (as they are idle, we do not expect userspace
59 * to be cleaning up anytime soon).
61 * If the timeline is currently locked, either it is being
62 * retired elsewhere or about to be!
64 if (mutex_trylock(&tl->mutex)) {
66 mutex_unlock(&tl->mutex);
68 intel_timeline_put(tl);
71 tl = ptr_mask_bits(next, 1);
75 static bool add_retire(struct intel_engine_cs *engine,
76 struct intel_timeline *tl)
78 #define STUB ((struct intel_timeline *)1)
79 struct intel_timeline *first;
82 * We open-code a llist here to include the additional tag [BIT(0)]
83 * so that we know when the timeline is already on a
84 * retirement queue: either this engine or another.
87 if (cmpxchg(&tl->retire, NULL, STUB)) /* already queued */
90 intel_timeline_get(tl);
91 first = READ_ONCE(engine->retire);
93 tl->retire = ptr_pack_bits(first, 1, 1);
94 while (!try_cmpxchg(&engine->retire, &first, tl));
99 void intel_engine_add_retire(struct intel_engine_cs *engine,
100 struct intel_timeline *tl)
102 if (add_retire(engine, tl))
103 schedule_work(&engine->retire_work);
106 void intel_engine_init_retire(struct intel_engine_cs *engine)
108 INIT_WORK(&engine->retire_work, engine_retire);
111 void intel_engine_fini_retire(struct intel_engine_cs *engine)
113 flush_work(&engine->retire_work);
114 GEM_BUG_ON(engine->retire);
117 long intel_gt_retire_requests_timeout(struct intel_gt *gt, long timeout)
119 struct intel_gt_timelines *timelines = >->timelines;
120 struct intel_timeline *tl, *tn;
121 unsigned long active_count = 0;
125 interruptible = true;
126 if (unlikely(timeout < 0))
127 timeout = -timeout, interruptible = false;
129 flush_submission(gt); /* kick the ksoftirqd tasklets */
130 spin_lock(&timelines->lock);
131 list_for_each_entry_safe(tl, tn, &timelines->active_list, link) {
132 if (!mutex_trylock(&tl->mutex)) {
133 active_count++; /* report busy to caller, try again? */
137 intel_timeline_get(tl);
138 GEM_BUG_ON(!atomic_read(&tl->active_count));
139 atomic_inc(&tl->active_count); /* pin the list element */
140 spin_unlock(&timelines->lock);
143 struct dma_fence *fence;
145 fence = i915_active_fence_get(&tl->last_request);
147 timeout = dma_fence_wait_timeout(fence,
150 dma_fence_put(fence);
154 if (!retire_requests(tl) || flush_submission(gt))
157 spin_lock(&timelines->lock);
159 /* Resume iteration after dropping lock */
160 list_safe_reset_next(tl, tn, link);
161 if (atomic_dec_and_test(&tl->active_count))
164 mutex_unlock(&tl->mutex);
166 /* Defer the final release to after the spinlock */
167 if (refcount_dec_and_test(&tl->kref.refcount)) {
168 GEM_BUG_ON(atomic_read(&tl->active_count));
169 list_add(&tl->link, &free);
172 spin_unlock(&timelines->lock);
174 list_for_each_entry_safe(tl, tn, &free, link)
175 __intel_timeline_free(&tl->kref);
177 return active_count ? timeout : 0;
180 int intel_gt_wait_for_idle(struct intel_gt *gt, long timeout)
182 /* If the device is asleep, we have no requests outstanding */
183 if (!intel_gt_pm_is_awake(gt))
186 while ((timeout = intel_gt_retire_requests_timeout(gt, timeout)) > 0) {
188 if (signal_pending(current))
195 static void retire_work_handler(struct work_struct *work)
197 struct intel_gt *gt =
198 container_of(work, typeof(*gt), requests.retire_work.work);
200 schedule_delayed_work(>->requests.retire_work,
201 round_jiffies_up_relative(HZ));
202 intel_gt_retire_requests(gt);
205 void intel_gt_init_requests(struct intel_gt *gt)
207 INIT_DELAYED_WORK(>->requests.retire_work, retire_work_handler);
210 void intel_gt_park_requests(struct intel_gt *gt)
212 cancel_delayed_work(>->requests.retire_work);
215 void intel_gt_unpark_requests(struct intel_gt *gt)
217 schedule_delayed_work(>->requests.retire_work,
218 round_jiffies_up_relative(HZ));
221 void intel_gt_fini_requests(struct intel_gt *gt)
223 /* Wait until the work is marked as finished before unloading! */
224 cancel_delayed_work_sync(>->requests.retire_work);