18  * While the engine is active, we send a periodic pulse along the engine
20  * is stuck, and we fail to preempt it, we declare the engine hung and
24 static bool next_heartbeat(struct intel_engine_cs *engine)  in next_heartbeat()  argument
28 	delay = READ_ONCE(engine->props.heartbeat_interval_ms);  in next_heartbeat()
35 	mod_delayed_work(system_highpri_wq, &engine->heartbeat.work, delay);  in next_heartbeat()
40 static void idle_pulse(struct intel_engine_cs *engine, struct i915_request *rq)  in idle_pulse()  argument
42 	engine->wakeref_serial = READ_ONCE(engine->serial) + 1;  in idle_pulse()
47 			   struct intel_engine_cs *engine)  in show_heartbeat()  argument
51 	intel_engine_dump(engine, &p,  in show_heartbeat()
53 			  engine->name,  in show_heartbeat()
64 	struct intel_engine_cs *engine =  in heartbeat()  local
65 		container_of(wrk, typeof(*engine), heartbeat.work.work);  in heartbeat()
66 	struct intel_context *ce = engine->kernel_context;  in heartbeat()
71 	intel_engine_flush_submission(engine);  in heartbeat()
73 	rq = engine->heartbeat.systole;  in heartbeat()
76 		engine->heartbeat.systole = NULL;  in heartbeat()
79 	if (!intel_engine_pm_get_if_awake(engine))  in heartbeat()
82 	if (intel_gt_is_wedged(engine->gt))  in heartbeat()
85 	if (engine->heartbeat.systole) {  in heartbeat()
97 		} else if (engine->schedule &&  in heartbeat()
112 			engine->schedule(rq, &attr);  in heartbeat()
116 				show_heartbeat(rq, engine);  in heartbeat()
118 			intel_gt_handle_error(engine->gt, engine->mask,  in heartbeat()
121 					      engine->name);  in heartbeat()
126 	serial = READ_ONCE(engine->serial);  in heartbeat()
127 	if (engine->wakeref_serial == serial)  in heartbeat()
131 		/* Unable to lock the kernel timeline, is the engine stuck? */  in heartbeat()
132 		if (xchg(&engine->heartbeat.blocked, serial) == serial)  in heartbeat()
133 			intel_gt_handle_error(engine->gt, engine->mask,  in heartbeat()
136 					      engine->name);  in heartbeat()
146 	idle_pulse(engine, rq);  in heartbeat()
147 	if (engine->i915->params.enable_hangcheck)  in heartbeat()
148 		engine->heartbeat.systole = i915_request_get(rq);  in heartbeat()
156 	if (!next_heartbeat(engine))  in heartbeat()
157 		i915_request_put(fetch_and_zero(&engine->heartbeat.systole));  in heartbeat()
158 	intel_engine_pm_put(engine);  in heartbeat()
161 void intel_engine_unpark_heartbeat(struct intel_engine_cs *engine)  in intel_engine_unpark_heartbeat()  argument
166 	next_heartbeat(engine);  in intel_engine_unpark_heartbeat()
169 void intel_engine_park_heartbeat(struct intel_engine_cs *engine)  in intel_engine_park_heartbeat()  argument
171 	if (cancel_delayed_work(&engine->heartbeat.work))  in intel_engine_park_heartbeat()
172 		i915_request_put(fetch_and_zero(&engine->heartbeat.systole));  in intel_engine_park_heartbeat()
175 void intel_engine_init_heartbeat(struct intel_engine_cs *engine)  in intel_engine_init_heartbeat()  argument
177 	INIT_DELAYED_WORK(&engine->heartbeat.work, heartbeat);  in intel_engine_init_heartbeat()
180 static int __intel_engine_pulse(struct intel_engine_cs *engine)  in __intel_engine_pulse()  argument
183 	struct intel_context *ce = engine->kernel_context;  in __intel_engine_pulse()
187 	GEM_BUG_ON(!intel_engine_has_preemption(engine));  in __intel_engine_pulse()
188 	GEM_BUG_ON(!intel_engine_pm_is_awake(engine));  in __intel_engine_pulse()
197 	idle_pulse(engine, rq);  in __intel_engine_pulse()
206 static unsigned long set_heartbeat(struct intel_engine_cs *engine,  in set_heartbeat()  argument
211 	old = xchg(&engine->props.heartbeat_interval_ms, delay);  in set_heartbeat()
213 		intel_engine_unpark_heartbeat(engine);  in set_heartbeat()
215 		intel_engine_park_heartbeat(engine);  in set_heartbeat()
220 int intel_engine_set_heartbeat(struct intel_engine_cs *engine,  in intel_engine_set_heartbeat()  argument
223 	struct intel_context *ce = engine->kernel_context;  in intel_engine_set_heartbeat()
226 	if (!delay && !intel_engine_has_preempt_reset(engine))  in intel_engine_set_heartbeat()
229 	intel_engine_pm_get(engine);  in intel_engine_set_heartbeat()
235 	if (delay != engine->props.heartbeat_interval_ms) {  in intel_engine_set_heartbeat()
236 		unsigned long saved = set_heartbeat(engine, delay);  in intel_engine_set_heartbeat()
239 		if (intel_engine_has_preemption(engine)) {  in intel_engine_set_heartbeat()
240 			err = __intel_engine_pulse(engine);  in intel_engine_set_heartbeat()
242 				set_heartbeat(engine, saved);  in intel_engine_set_heartbeat()
249 	intel_engine_pm_put(engine);  in intel_engine_set_heartbeat()
253 int intel_engine_pulse(struct intel_engine_cs *engine)  in intel_engine_pulse()  argument
255 	struct intel_context *ce = engine->kernel_context;  in intel_engine_pulse()
258 	if (!intel_engine_has_preemption(engine))  in intel_engine_pulse()
261 	if (!intel_engine_pm_get_if_awake(engine))  in intel_engine_pulse()
266 		err = __intel_engine_pulse(engine);  in intel_engine_pulse()
270 	intel_engine_pm_put(engine);  in intel_engine_pulse()
274 int intel_engine_flush_barriers(struct intel_engine_cs *engine)  in intel_engine_flush_barriers()  argument
279 	if (llist_empty(&engine->barrier_tasks))  in intel_engine_flush_barriers()
282 	if (!intel_engine_pm_get_if_awake(engine))  in intel_engine_flush_barriers()
285 	rq = i915_request_create(engine->kernel_context);  in intel_engine_flush_barriers()
291 	idle_pulse(engine, rq);  in intel_engine_flush_barriers()
295 	intel_engine_pm_put(engine);  in intel_engine_flush_barriers()