2 * Copyright © 2015 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
25 #include <linux/kthread.h>
26 #include <trace/events/dma_fence.h>
27 #include <uapi/linux/sched/types.h>
30 #include "i915_trace.h"
31 #include "intel_gt_pm.h"
32 #include "intel_gt_requests.h"
34 static void irq_enable(struct intel_engine_cs *engine)
36 if (!engine->irq_enable)
39 /* Caller disables interrupts */
40 spin_lock(&engine->gt->irq_lock);
41 engine->irq_enable(engine);
42 spin_unlock(&engine->gt->irq_lock);
45 static void irq_disable(struct intel_engine_cs *engine)
47 if (!engine->irq_disable)
50 /* Caller disables interrupts */
51 spin_lock(&engine->gt->irq_lock);
52 engine->irq_disable(engine);
53 spin_unlock(&engine->gt->irq_lock);
56 static void __intel_breadcrumbs_disarm_irq(struct intel_breadcrumbs *b)
58 struct intel_engine_cs *engine =
59 container_of(b, struct intel_engine_cs, breadcrumbs);
61 lockdep_assert_held(&b->irq_lock);
63 GEM_BUG_ON(!b->irq_enabled);
64 if (!--b->irq_enabled)
68 intel_gt_pm_put_async(engine->gt);
71 void intel_engine_disarm_breadcrumbs(struct intel_engine_cs *engine)
73 struct intel_breadcrumbs *b = &engine->breadcrumbs;
79 spin_lock_irqsave(&b->irq_lock, flags);
81 __intel_breadcrumbs_disarm_irq(b);
82 spin_unlock_irqrestore(&b->irq_lock, flags);
85 static inline bool __request_completed(const struct i915_request *rq)
87 return i915_seqno_passed(__hwsp_seqno(rq), rq->fence.seqno);
90 __maybe_unused static bool
91 check_signal_order(struct intel_context *ce, struct i915_request *rq)
93 if (!list_is_last(&rq->signal_link, &ce->signals) &&
94 i915_seqno_passed(rq->fence.seqno,
95 list_next_entry(rq, signal_link)->fence.seqno))
98 if (!list_is_first(&rq->signal_link, &ce->signals) &&
99 i915_seqno_passed(list_prev_entry(rq, signal_link)->fence.seqno,
107 __dma_fence_signal(struct dma_fence *fence)
109 return !test_and_set_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags);
113 __dma_fence_signal__timestamp(struct dma_fence *fence, ktime_t timestamp)
115 fence->timestamp = timestamp;
116 set_bit(DMA_FENCE_FLAG_TIMESTAMP_BIT, &fence->flags);
117 trace_dma_fence_signaled(fence);
121 __dma_fence_signal__notify(struct dma_fence *fence,
122 const struct list_head *list)
124 struct dma_fence_cb *cur, *tmp;
126 lockdep_assert_held(fence->lock);
128 list_for_each_entry_safe(cur, tmp, list, node) {
129 INIT_LIST_HEAD(&cur->node);
130 cur->func(fence, cur);
134 static void add_retire(struct intel_breadcrumbs *b, struct intel_timeline *tl)
136 struct intel_engine_cs *engine =
137 container_of(b, struct intel_engine_cs, breadcrumbs);
139 intel_engine_add_retire(engine, tl);
142 static void signal_irq_work(struct irq_work *work)
144 struct intel_breadcrumbs *b = container_of(work, typeof(*b), irq_work);
145 const ktime_t timestamp = ktime_get();
146 struct intel_context *ce, *cn;
147 struct list_head *pos, *next;
150 spin_lock(&b->irq_lock);
152 if (b->irq_armed && list_empty(&b->signalers))
153 __intel_breadcrumbs_disarm_irq(b);
155 list_for_each_entry_safe(ce, cn, &b->signalers, signal_link) {
156 GEM_BUG_ON(list_empty(&ce->signals));
158 list_for_each_safe(pos, next, &ce->signals) {
159 struct i915_request *rq =
160 list_entry(pos, typeof(*rq), signal_link);
162 GEM_BUG_ON(!check_signal_order(ce, rq));
164 if (!__request_completed(rq))
167 GEM_BUG_ON(!test_bit(I915_FENCE_FLAG_SIGNAL,
169 clear_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
171 if (!__dma_fence_signal(&rq->fence))
175 * Queue for execution after dropping the signaling
176 * spinlock as the callback chain may end up adding
177 * more signalers to the same context or engine.
179 i915_request_get(rq);
180 list_add_tail(&rq->signal_link, &signal);
184 * We process the list deletion in bulk, only using a list_add
185 * (not list_move) above but keeping the status of
186 * rq->signal_link known with the I915_FENCE_FLAG_SIGNAL bit.
188 if (!list_is_first(pos, &ce->signals)) {
189 /* Advance the list to the first incomplete request */
190 __list_del_many(&ce->signals, pos);
191 if (&ce->signals == pos) { /* now empty */
192 list_del_init(&ce->signal_link);
193 add_retire(b, ce->timeline);
198 spin_unlock(&b->irq_lock);
200 list_for_each_safe(pos, next, &signal) {
201 struct i915_request *rq =
202 list_entry(pos, typeof(*rq), signal_link);
203 struct list_head cb_list;
205 spin_lock(&rq->lock);
206 list_replace(&rq->fence.cb_list, &cb_list);
207 __dma_fence_signal__timestamp(&rq->fence, timestamp);
208 __dma_fence_signal__notify(&rq->fence, &cb_list);
209 spin_unlock(&rq->lock);
211 i915_request_put(rq);
215 static bool __intel_breadcrumbs_arm_irq(struct intel_breadcrumbs *b)
217 struct intel_engine_cs *engine =
218 container_of(b, struct intel_engine_cs, breadcrumbs);
220 lockdep_assert_held(&b->irq_lock);
224 if (!intel_gt_pm_get_if_awake(engine->gt))
228 * The breadcrumb irq will be disarmed on the interrupt after the
229 * waiters are signaled. This gives us a single interrupt window in
230 * which we can add a new waiter and avoid the cost of re-enabling
236 * Since we are waiting on a request, the GPU should be busy
237 * and should have its own rpm reference. This is tracked
238 * by i915->gt.awake, we can forgo holding our own wakref
239 * for the interrupt as before i915->gt.awake is released (when
240 * the driver is idle) we disarm the breadcrumbs.
243 if (!b->irq_enabled++)
249 void intel_engine_init_breadcrumbs(struct intel_engine_cs *engine)
251 struct intel_breadcrumbs *b = &engine->breadcrumbs;
253 spin_lock_init(&b->irq_lock);
254 INIT_LIST_HEAD(&b->signalers);
256 init_irq_work(&b->irq_work, signal_irq_work);
259 void intel_engine_reset_breadcrumbs(struct intel_engine_cs *engine)
261 struct intel_breadcrumbs *b = &engine->breadcrumbs;
264 spin_lock_irqsave(&b->irq_lock, flags);
271 spin_unlock_irqrestore(&b->irq_lock, flags);
274 void intel_engine_fini_breadcrumbs(struct intel_engine_cs *engine)
278 bool i915_request_enable_breadcrumb(struct i915_request *rq)
280 lockdep_assert_held(&rq->lock);
282 if (test_bit(I915_FENCE_FLAG_ACTIVE, &rq->fence.flags)) {
283 struct intel_breadcrumbs *b = &rq->engine->breadcrumbs;
284 struct intel_context *ce = rq->context;
285 struct list_head *pos;
287 spin_lock(&b->irq_lock);
288 GEM_BUG_ON(test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags));
290 if (!__intel_breadcrumbs_arm_irq(b))
294 * We keep the seqno in retirement order, so we can break
295 * inside intel_engine_signal_breadcrumbs as soon as we've
296 * passed the last completed request (or seen a request that
297 * hasn't event started). We could walk the timeline->requests,
298 * but keeping a separate signalers_list has the advantage of
299 * hopefully being much smaller than the full list and so
300 * provides faster iteration and detection when there are no
301 * more interrupts required for this context.
303 * We typically expect to add new signalers in order, so we
304 * start looking for our insertion point from the tail of
307 list_for_each_prev(pos, &ce->signals) {
308 struct i915_request *it =
309 list_entry(pos, typeof(*it), signal_link);
311 if (i915_seqno_passed(rq->fence.seqno, it->fence.seqno))
314 list_add(&rq->signal_link, pos);
315 if (pos == &ce->signals) /* catch transitions from empty list */
316 list_move_tail(&ce->signal_link, &b->signalers);
317 GEM_BUG_ON(!check_signal_order(ce, rq));
319 set_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
321 spin_unlock(&b->irq_lock);
324 return !__request_completed(rq);
327 void i915_request_cancel_breadcrumb(struct i915_request *rq)
329 struct intel_breadcrumbs *b = &rq->engine->breadcrumbs;
331 lockdep_assert_held(&rq->lock);
334 * We must wait for b->irq_lock so that we know the interrupt handler
335 * has released its reference to the intel_context and has completed
336 * the DMA_FENCE_FLAG_SIGNALED_BIT/I915_FENCE_FLAG_SIGNAL dance (if
339 spin_lock(&b->irq_lock);
340 if (test_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags)) {
341 struct intel_context *ce = rq->context;
343 list_del(&rq->signal_link);
344 if (list_empty(&ce->signals))
345 list_del_init(&ce->signal_link);
347 clear_bit(I915_FENCE_FLAG_SIGNAL, &rq->fence.flags);
349 spin_unlock(&b->irq_lock);
352 void intel_engine_print_breadcrumbs(struct intel_engine_cs *engine,
353 struct drm_printer *p)
355 struct intel_breadcrumbs *b = &engine->breadcrumbs;
356 struct intel_context *ce;
357 struct i915_request *rq;
359 if (list_empty(&b->signalers))
362 drm_printf(p, "Signals:\n");
364 spin_lock_irq(&b->irq_lock);
365 list_for_each_entry(ce, &b->signalers, signal_link) {
366 list_for_each_entry(rq, &ce->signals, signal_link) {
367 drm_printf(p, "\t[%llx:%llx%s] @ %dms\n",
368 rq->fence.context, rq->fence.seqno,
369 i915_request_completed(rq) ? "!" :
370 i915_request_started(rq) ? "*" :
372 jiffies_to_msecs(jiffies - rq->emitted_jiffies));
375 spin_unlock_irq(&b->irq_lock);