1 // SPDX-License-Identifier: GPL-2.0
3  * trace task wakeup timings
5  * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
10  *  Copyright (C) 2004-2006 Ingo Molnar
28 static unsigned			wakeup_prio = -1;
44 # define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH)
54  * Prologue for the wakeup function tracers.
57  *            is disabled and data->disabled is incremented.
59  *            is not disabled and data->disabled is
85 	*data = per_cpu_ptr(tr->array_buffer.data, cpu);  in func_prolog_preempt_disable()
86 	disabled = atomic_inc_return(&(*data)->disabled);  in func_prolog_preempt_disable()
93 	atomic_dec(&(*data)->disabled);  in func_prolog_preempt_disable()
110 	tr->max_latency = 0;  in wakeup_display_graph()
134 	if (ftrace_graph_notrace_addr(trace->func))  in wakeup_graph_entry()
140 	calltime = fgraph_reserve_data(gops->idx, sizeof(*calltime));  in wakeup_graph_entry()
147 	atomic_dec(&data->disabled);  in wakeup_graph_entry()
171 	calltime = fgraph_retrieve_data(gops->idx, &size);  in wakeup_graph_return()
176 	atomic_dec(&data->disabled);  in wakeup_graph_return()
189 	if (is_graph(iter->tr))  in wakeup_trace_open()
192 		iter->private = NULL;  in wakeup_trace_open()
197 	if (iter->private)  in wakeup_trace_close()
214 	if (is_graph(iter->tr))  in wakeup_print_line()
230  * wakeup uses its own tracer function to keep the overhead down:
248 	atomic_dec(&data->disabled);  in wakeup_tracer_call()
257 	if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION)))  in register_wakeup_function()
263 		ret = register_ftrace_function(tr->ops);  in register_wakeup_function()
279 		unregister_ftrace_function(tr->ops);  in unregister_wakeup_function()
335 	struct tracer *tracer = tr->current_trace;  in wakeup_flag_changed()
370  * Should this new latency be reported/recorded?
378 		if (delta <= tr->max_latency)  in report_latency()
399 	struct trace_buffer *buffer = tr->array_buffer.buffer;  in tracing_sched_switch_trace()
408 	entry->prev_pid			= prev->pid;  in tracing_sched_switch_trace()
409 	entry->prev_prio		= prev->prio;  in tracing_sched_switch_trace()
410 	entry->prev_state		= task_state_index(prev);  in tracing_sched_switch_trace()
411 	entry->next_pid			= next->pid;  in tracing_sched_switch_trace()
412 	entry->next_prio		= next->prio;  in tracing_sched_switch_trace()
413 	entry->next_state		= task_state_index(next);  in tracing_sched_switch_trace()
414 	entry->next_cpu	= task_cpu(next);  in tracing_sched_switch_trace()
427 	struct trace_buffer *buffer = tr->array_buffer.buffer;  in tracing_sched_wakeup_trace()
434 	entry->prev_pid			= curr->pid;  in tracing_sched_wakeup_trace()
435 	entry->prev_prio		= curr->prio;  in tracing_sched_wakeup_trace()
436 	entry->prev_state		= task_state_index(curr);  in tracing_sched_wakeup_trace()
437 	entry->next_pid			= wakee->pid;  in tracing_sched_wakeup_trace()
438 	entry->next_prio		= wakee->prio;  in tracing_sched_wakeup_trace()
439 	entry->next_state		= task_state_index(wakee);  in tracing_sched_wakeup_trace()
440 	entry->next_cpu			= task_cpu(wakee);  in tracing_sched_wakeup_trace()
476 	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);  in probe_wakeup_sched_switch()
490 	data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);  in probe_wakeup_sched_switch()
496 	T0 = data->preempt_timestamp;  in probe_wakeup_sched_switch()
498 	delta = T1-T0;  in probe_wakeup_sched_switch()
504 		wakeup_trace->max_latency = delta;  in probe_wakeup_sched_switch()
513 	atomic_dec(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);  in probe_wakeup_sched_switch()
518 	wakeup_cpu = -1;  in __wakeup_reset()
519 	wakeup_prio = -1;  in __wakeup_reset()
532 	tracing_reset_online_cpus(&tr->array_buffer);  in wakeup_reset()
557 	 *  - wakeup tracer handles all tasks in the system, independently  in probe_wakeup()
559 	 *  - wakeup_rt tracer handles tasks belonging to sched_dl and  in probe_wakeup()
561 	 *  - wakeup_dl handles tasks belonging to sched_dl class only.  in probe_wakeup()
565 	    (!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio)))  in probe_wakeup()
568 	disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);  in probe_wakeup()
579 	    (!dl_task(p) && p->prio >= wakeup_prio))  in probe_wakeup()
587 	wakeup_prio = p->prio;  in probe_wakeup()
590 	 * Once you start tracing a -deadline task, don't bother tracing  in probe_wakeup()
600 	data = per_cpu_ptr(wakeup_trace->array_buffer.data, wakeup_cpu);  in probe_wakeup()
601 	data->preempt_timestamp = ftrace_now(cpu);  in probe_wakeup()
615 	atomic_dec(&per_cpu_ptr(wakeup_trace->array_buffer.data, cpu)->disabled);  in probe_wakeup()
624 		pr_info("wakeup trace: Couldn't activate tracepoint"  in start_wakeup_tracer()
631 		pr_info("wakeup trace: Couldn't activate tracepoint"  in start_wakeup_tracer()
645 		pr_info("wakeup trace: Couldn't activate tracepoint"  in start_wakeup_tracer()
662 		printk(KERN_ERR "failed to start wakeup tracer\n");  in start_wakeup_tracer()
687 	save_flags = tr->trace_flags;  in __wakeup_tracer_init()
689 	/* non overwrite screws up the latency tracers */  in __wakeup_tracer_init()
693 	tr->max_latency = 0;  in __wakeup_tracer_init()
705 		return -EBUSY;  in wakeup_tracer_init()
715 		return -EBUSY;  in wakeup_rt_tracer_init()
725 		return -EBUSY;  in wakeup_dl_tracer_init()
760 	.name		= "wakeup",