forked from Minki/linux
8a103df440
Signed-off-by: Ingo Molnar <mingo@kernel.org>
829 lines
20 KiB
C
829 lines
20 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* trace task wakeup timings
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*
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* Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
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* Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
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*
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* Based on code from the latency_tracer, that is:
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*
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* Copyright (C) 2004-2006 Ingo Molnar
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* Copyright (C) 2004 Nadia Yvette Chambers
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*/
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#include <linux/module.h>
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#include <linux/kallsyms.h>
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#include <linux/uaccess.h>
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#include <linux/ftrace.h>
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#include <linux/sched/rt.h>
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#include <linux/sched/deadline.h>
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#include <trace/events/sched.h>
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#include "trace.h"
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static struct trace_array *wakeup_trace;
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static int __read_mostly tracer_enabled;
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static struct task_struct *wakeup_task;
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static int wakeup_cpu;
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static int wakeup_current_cpu;
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static unsigned wakeup_prio = -1;
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static int wakeup_rt;
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static int wakeup_dl;
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static int tracing_dl = 0;
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static arch_spinlock_t wakeup_lock =
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(arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
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static void wakeup_reset(struct trace_array *tr);
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static void __wakeup_reset(struct trace_array *tr);
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static int save_flags;
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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static int wakeup_display_graph(struct trace_array *tr, int set);
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# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH)
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#else
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static inline int wakeup_display_graph(struct trace_array *tr, int set)
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{
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return 0;
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}
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# define is_graph(tr) false
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#endif
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#ifdef CONFIG_FUNCTION_TRACER
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static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
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static void wakeup_graph_return(struct ftrace_graph_ret *trace);
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static bool function_enabled;
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/*
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* Prologue for the wakeup function tracers.
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*
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* Returns 1 if it is OK to continue, and preemption
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* is disabled and data->disabled is incremented.
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* 0 if the trace is to be ignored, and preemption
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* is not disabled and data->disabled is
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* kept the same.
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*
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* Note, this function is also used outside this ifdef but
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* inside the #ifdef of the function graph tracer below.
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* This is OK, since the function graph tracer is
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* dependent on the function tracer.
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*/
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static int
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func_prolog_preempt_disable(struct trace_array *tr,
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struct trace_array_cpu **data,
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int *pc)
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{
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long disabled;
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int cpu;
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if (likely(!wakeup_task))
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return 0;
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*pc = preempt_count();
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preempt_disable_notrace();
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cpu = raw_smp_processor_id();
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if (cpu != wakeup_current_cpu)
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goto out_enable;
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*data = per_cpu_ptr(tr->trace_buffer.data, cpu);
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disabled = atomic_inc_return(&(*data)->disabled);
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if (unlikely(disabled != 1))
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goto out;
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return 1;
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out:
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atomic_dec(&(*data)->disabled);
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out_enable:
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preempt_enable_notrace();
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return 0;
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}
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/*
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* wakeup uses its own tracer function to keep the overhead down:
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*/
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static void
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wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
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struct ftrace_ops *op, struct pt_regs *pt_regs)
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{
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struct trace_array *tr = wakeup_trace;
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struct trace_array_cpu *data;
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unsigned long flags;
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int pc;
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if (!func_prolog_preempt_disable(tr, &data, &pc))
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return;
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local_irq_save(flags);
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trace_function(tr, ip, parent_ip, flags, pc);
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local_irq_restore(flags);
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atomic_dec(&data->disabled);
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preempt_enable_notrace();
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}
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static int register_wakeup_function(struct trace_array *tr, int graph, int set)
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{
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int ret;
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/* 'set' is set if TRACE_ITER_FUNCTION is about to be set */
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if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION)))
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return 0;
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if (graph)
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ret = register_ftrace_graph(&wakeup_graph_return,
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&wakeup_graph_entry);
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else
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ret = register_ftrace_function(tr->ops);
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if (!ret)
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function_enabled = true;
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return ret;
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}
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static void unregister_wakeup_function(struct trace_array *tr, int graph)
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{
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if (!function_enabled)
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return;
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if (graph)
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unregister_ftrace_graph();
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else
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unregister_ftrace_function(tr->ops);
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function_enabled = false;
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}
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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
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{
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if (!(mask & TRACE_ITER_FUNCTION))
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return 0;
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if (set)
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register_wakeup_function(tr, is_graph(tr), 1);
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else
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unregister_wakeup_function(tr, is_graph(tr));
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return 1;
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}
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#else
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static int register_wakeup_function(struct trace_array *tr, int graph, int set)
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{
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return 0;
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}
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static void unregister_wakeup_function(struct trace_array *tr, int graph) { }
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static int wakeup_function_set(struct trace_array *tr, u32 mask, int set)
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{
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return 0;
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}
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#endif /* CONFIG_FUNCTION_TRACER */
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static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
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{
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struct tracer *tracer = tr->current_trace;
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if (wakeup_function_set(tr, mask, set))
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return 0;
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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if (mask & TRACE_ITER_DISPLAY_GRAPH)
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return wakeup_display_graph(tr, set);
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#endif
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return trace_keep_overwrite(tracer, mask, set);
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}
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static int start_func_tracer(struct trace_array *tr, int graph)
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{
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int ret;
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ret = register_wakeup_function(tr, graph, 0);
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if (!ret && tracing_is_enabled())
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tracer_enabled = 1;
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else
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tracer_enabled = 0;
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return ret;
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}
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static void stop_func_tracer(struct trace_array *tr, int graph)
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{
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tracer_enabled = 0;
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unregister_wakeup_function(tr, graph);
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}
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#ifdef CONFIG_FUNCTION_GRAPH_TRACER
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static int wakeup_display_graph(struct trace_array *tr, int set)
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{
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if (!(is_graph(tr) ^ set))
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return 0;
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stop_func_tracer(tr, !set);
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wakeup_reset(wakeup_trace);
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tr->max_latency = 0;
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return start_func_tracer(tr, set);
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}
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static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
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{
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struct trace_array *tr = wakeup_trace;
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struct trace_array_cpu *data;
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unsigned long flags;
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int pc, ret = 0;
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if (ftrace_graph_ignore_func(trace))
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return 0;
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/*
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* Do not trace a function if it's filtered by set_graph_notrace.
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* Make the index of ret stack negative to indicate that it should
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* ignore further functions. But it needs its own ret stack entry
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* to recover the original index in order to continue tracing after
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* returning from the function.
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*/
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if (ftrace_graph_notrace_addr(trace->func))
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return 1;
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if (!func_prolog_preempt_disable(tr, &data, &pc))
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return 0;
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local_save_flags(flags);
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ret = __trace_graph_entry(tr, trace, flags, pc);
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atomic_dec(&data->disabled);
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preempt_enable_notrace();
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return ret;
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}
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static void wakeup_graph_return(struct ftrace_graph_ret *trace)
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{
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struct trace_array *tr = wakeup_trace;
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struct trace_array_cpu *data;
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unsigned long flags;
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int pc;
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if (!func_prolog_preempt_disable(tr, &data, &pc))
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return;
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local_save_flags(flags);
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__trace_graph_return(tr, trace, flags, pc);
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atomic_dec(&data->disabled);
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preempt_enable_notrace();
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return;
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}
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static void wakeup_trace_open(struct trace_iterator *iter)
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{
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if (is_graph(iter->tr))
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graph_trace_open(iter);
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}
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static void wakeup_trace_close(struct trace_iterator *iter)
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{
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if (iter->private)
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graph_trace_close(iter);
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}
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#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \
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TRACE_GRAPH_PRINT_ABS_TIME | \
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TRACE_GRAPH_PRINT_DURATION)
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static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
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{
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/*
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* In graph mode call the graph tracer output function,
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* otherwise go with the TRACE_FN event handler
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*/
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if (is_graph(iter->tr))
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return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS);
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return TRACE_TYPE_UNHANDLED;
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}
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static void wakeup_print_header(struct seq_file *s)
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{
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if (is_graph(wakeup_trace))
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print_graph_headers_flags(s, GRAPH_TRACER_FLAGS);
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else
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trace_default_header(s);
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}
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static void
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__trace_function(struct trace_array *tr,
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unsigned long ip, unsigned long parent_ip,
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unsigned long flags, int pc)
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{
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if (is_graph(tr))
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trace_graph_function(tr, ip, parent_ip, flags, pc);
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else
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trace_function(tr, ip, parent_ip, flags, pc);
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}
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#else
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#define __trace_function trace_function
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static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
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{
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return TRACE_TYPE_UNHANDLED;
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}
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static void wakeup_trace_open(struct trace_iterator *iter) { }
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static void wakeup_trace_close(struct trace_iterator *iter) { }
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#ifdef CONFIG_FUNCTION_TRACER
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static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
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{
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return -1;
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}
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static void wakeup_graph_return(struct ftrace_graph_ret *trace) { }
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static void wakeup_print_header(struct seq_file *s)
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{
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trace_default_header(s);
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}
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#else
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static void wakeup_print_header(struct seq_file *s)
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{
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trace_latency_header(s);
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}
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#endif /* CONFIG_FUNCTION_TRACER */
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#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
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/*
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* Should this new latency be reported/recorded?
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*/
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static bool report_latency(struct trace_array *tr, u64 delta)
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{
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if (tracing_thresh) {
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if (delta < tracing_thresh)
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return false;
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} else {
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if (delta <= tr->max_latency)
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return false;
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}
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return true;
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}
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static void
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probe_wakeup_migrate_task(void *ignore, struct task_struct *task, int cpu)
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{
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if (task != wakeup_task)
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return;
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wakeup_current_cpu = cpu;
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}
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static void
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tracing_sched_switch_trace(struct trace_array *tr,
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struct task_struct *prev,
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struct task_struct *next,
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unsigned long flags, int pc)
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{
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struct trace_event_call *call = &event_context_switch;
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struct ring_buffer *buffer = tr->trace_buffer.buffer;
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struct ring_buffer_event *event;
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struct ctx_switch_entry *entry;
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event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
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sizeof(*entry), flags, pc);
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if (!event)
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return;
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entry = ring_buffer_event_data(event);
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entry->prev_pid = prev->pid;
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entry->prev_prio = prev->prio;
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entry->prev_state = task_state_index(prev);
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entry->next_pid = next->pid;
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entry->next_prio = next->prio;
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entry->next_state = task_state_index(next);
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entry->next_cpu = task_cpu(next);
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if (!call_filter_check_discard(call, entry, buffer, event))
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trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
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}
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static void
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tracing_sched_wakeup_trace(struct trace_array *tr,
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struct task_struct *wakee,
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struct task_struct *curr,
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unsigned long flags, int pc)
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{
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struct trace_event_call *call = &event_wakeup;
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struct ring_buffer_event *event;
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struct ctx_switch_entry *entry;
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struct ring_buffer *buffer = tr->trace_buffer.buffer;
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event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
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sizeof(*entry), flags, pc);
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if (!event)
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return;
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entry = ring_buffer_event_data(event);
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entry->prev_pid = curr->pid;
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entry->prev_prio = curr->prio;
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entry->prev_state = task_state_index(curr);
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entry->next_pid = wakee->pid;
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entry->next_prio = wakee->prio;
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entry->next_state = task_state_index(wakee);
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entry->next_cpu = task_cpu(wakee);
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if (!call_filter_check_discard(call, entry, buffer, event))
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trace_buffer_unlock_commit(tr, buffer, event, flags, pc);
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}
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static void notrace
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probe_wakeup_sched_switch(void *ignore, bool preempt,
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struct task_struct *prev, struct task_struct *next)
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{
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struct trace_array_cpu *data;
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u64 T0, T1, delta;
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unsigned long flags;
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long disabled;
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int cpu;
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int pc;
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tracing_record_cmdline(prev);
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if (unlikely(!tracer_enabled))
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return;
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/*
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* When we start a new trace, we set wakeup_task to NULL
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* and then set tracer_enabled = 1. We want to make sure
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* that another CPU does not see the tracer_enabled = 1
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* and the wakeup_task with an older task, that might
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* actually be the same as next.
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*/
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smp_rmb();
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if (next != wakeup_task)
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return;
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pc = preempt_count();
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/* disable local data, not wakeup_cpu data */
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cpu = raw_smp_processor_id();
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disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
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if (likely(disabled != 1))
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goto out;
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local_irq_save(flags);
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arch_spin_lock(&wakeup_lock);
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/* We could race with grabbing wakeup_lock */
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if (unlikely(!tracer_enabled || next != wakeup_task))
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goto out_unlock;
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/* The task we are waiting for is waking up */
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data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);
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__trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
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tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
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T0 = data->preempt_timestamp;
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T1 = ftrace_now(cpu);
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delta = T1-T0;
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if (!report_latency(wakeup_trace, delta))
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goto out_unlock;
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if (likely(!is_tracing_stopped())) {
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wakeup_trace->max_latency = delta;
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update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
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}
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out_unlock:
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__wakeup_reset(wakeup_trace);
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arch_spin_unlock(&wakeup_lock);
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local_irq_restore(flags);
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out:
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atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
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}
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static void __wakeup_reset(struct trace_array *tr)
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{
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wakeup_cpu = -1;
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wakeup_prio = -1;
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tracing_dl = 0;
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if (wakeup_task)
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put_task_struct(wakeup_task);
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wakeup_task = NULL;
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}
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static void wakeup_reset(struct trace_array *tr)
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{
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unsigned long flags;
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tracing_reset_online_cpus(&tr->trace_buffer);
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local_irq_save(flags);
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arch_spin_lock(&wakeup_lock);
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__wakeup_reset(tr);
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arch_spin_unlock(&wakeup_lock);
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local_irq_restore(flags);
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}
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static void
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probe_wakeup(void *ignore, struct task_struct *p)
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{
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struct trace_array_cpu *data;
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int cpu = smp_processor_id();
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unsigned long flags;
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long disabled;
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int pc;
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if (likely(!tracer_enabled))
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return;
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tracing_record_cmdline(p);
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tracing_record_cmdline(current);
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/*
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* Semantic is like this:
|
|
* - wakeup tracer handles all tasks in the system, independently
|
|
* from their scheduling class;
|
|
* - wakeup_rt tracer handles tasks belonging to sched_dl and
|
|
* sched_rt class;
|
|
* - wakeup_dl handles tasks belonging to sched_dl class only.
|
|
*/
|
|
if (tracing_dl || (wakeup_dl && !dl_task(p)) ||
|
|
(wakeup_rt && !dl_task(p) && !rt_task(p)) ||
|
|
(!dl_task(p) && (p->prio >= wakeup_prio || p->prio >= current->prio)))
|
|
return;
|
|
|
|
pc = preempt_count();
|
|
disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
|
|
if (unlikely(disabled != 1))
|
|
goto out;
|
|
|
|
/* interrupts should be off from try_to_wake_up */
|
|
arch_spin_lock(&wakeup_lock);
|
|
|
|
/* check for races. */
|
|
if (!tracer_enabled || tracing_dl ||
|
|
(!dl_task(p) && p->prio >= wakeup_prio))
|
|
goto out_locked;
|
|
|
|
/* reset the trace */
|
|
__wakeup_reset(wakeup_trace);
|
|
|
|
wakeup_cpu = task_cpu(p);
|
|
wakeup_current_cpu = wakeup_cpu;
|
|
wakeup_prio = p->prio;
|
|
|
|
/*
|
|
* Once you start tracing a -deadline task, don't bother tracing
|
|
* another task until the first one wakes up.
|
|
*/
|
|
if (dl_task(p))
|
|
tracing_dl = 1;
|
|
else
|
|
tracing_dl = 0;
|
|
|
|
wakeup_task = p;
|
|
get_task_struct(wakeup_task);
|
|
|
|
local_save_flags(flags);
|
|
|
|
data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);
|
|
data->preempt_timestamp = ftrace_now(cpu);
|
|
tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
|
|
|
|
/*
|
|
* We must be careful in using CALLER_ADDR2. But since wake_up
|
|
* is not called by an assembly function (where as schedule is)
|
|
* it should be safe to use it here.
|
|
*/
|
|
__trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
|
|
|
|
out_locked:
|
|
arch_spin_unlock(&wakeup_lock);
|
|
out:
|
|
atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
|
|
}
|
|
|
|
static void start_wakeup_tracer(struct trace_array *tr)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_trace_sched_wakeup(probe_wakeup, NULL);
|
|
if (ret) {
|
|
pr_info("wakeup trace: Couldn't activate tracepoint"
|
|
" probe to kernel_sched_wakeup\n");
|
|
return;
|
|
}
|
|
|
|
ret = register_trace_sched_wakeup_new(probe_wakeup, NULL);
|
|
if (ret) {
|
|
pr_info("wakeup trace: Couldn't activate tracepoint"
|
|
" probe to kernel_sched_wakeup_new\n");
|
|
goto fail_deprobe;
|
|
}
|
|
|
|
ret = register_trace_sched_switch(probe_wakeup_sched_switch, NULL);
|
|
if (ret) {
|
|
pr_info("sched trace: Couldn't activate tracepoint"
|
|
" probe to kernel_sched_switch\n");
|
|
goto fail_deprobe_wake_new;
|
|
}
|
|
|
|
ret = register_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
|
|
if (ret) {
|
|
pr_info("wakeup trace: Couldn't activate tracepoint"
|
|
" probe to kernel_sched_migrate_task\n");
|
|
return;
|
|
}
|
|
|
|
wakeup_reset(tr);
|
|
|
|
/*
|
|
* Don't let the tracer_enabled = 1 show up before
|
|
* the wakeup_task is reset. This may be overkill since
|
|
* wakeup_reset does a spin_unlock after setting the
|
|
* wakeup_task to NULL, but I want to be safe.
|
|
* This is a slow path anyway.
|
|
*/
|
|
smp_wmb();
|
|
|
|
if (start_func_tracer(tr, is_graph(tr)))
|
|
printk(KERN_ERR "failed to start wakeup tracer\n");
|
|
|
|
return;
|
|
fail_deprobe_wake_new:
|
|
unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
|
|
fail_deprobe:
|
|
unregister_trace_sched_wakeup(probe_wakeup, NULL);
|
|
}
|
|
|
|
static void stop_wakeup_tracer(struct trace_array *tr)
|
|
{
|
|
tracer_enabled = 0;
|
|
stop_func_tracer(tr, is_graph(tr));
|
|
unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL);
|
|
unregister_trace_sched_wakeup_new(probe_wakeup, NULL);
|
|
unregister_trace_sched_wakeup(probe_wakeup, NULL);
|
|
unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL);
|
|
}
|
|
|
|
static bool wakeup_busy;
|
|
|
|
static int __wakeup_tracer_init(struct trace_array *tr)
|
|
{
|
|
save_flags = tr->trace_flags;
|
|
|
|
/* non overwrite screws up the latency tracers */
|
|
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1);
|
|
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1);
|
|
|
|
tr->max_latency = 0;
|
|
wakeup_trace = tr;
|
|
ftrace_init_array_ops(tr, wakeup_tracer_call);
|
|
start_wakeup_tracer(tr);
|
|
|
|
wakeup_busy = true;
|
|
return 0;
|
|
}
|
|
|
|
static int wakeup_tracer_init(struct trace_array *tr)
|
|
{
|
|
if (wakeup_busy)
|
|
return -EBUSY;
|
|
|
|
wakeup_dl = 0;
|
|
wakeup_rt = 0;
|
|
return __wakeup_tracer_init(tr);
|
|
}
|
|
|
|
static int wakeup_rt_tracer_init(struct trace_array *tr)
|
|
{
|
|
if (wakeup_busy)
|
|
return -EBUSY;
|
|
|
|
wakeup_dl = 0;
|
|
wakeup_rt = 1;
|
|
return __wakeup_tracer_init(tr);
|
|
}
|
|
|
|
static int wakeup_dl_tracer_init(struct trace_array *tr)
|
|
{
|
|
if (wakeup_busy)
|
|
return -EBUSY;
|
|
|
|
wakeup_dl = 1;
|
|
wakeup_rt = 0;
|
|
return __wakeup_tracer_init(tr);
|
|
}
|
|
|
|
static void wakeup_tracer_reset(struct trace_array *tr)
|
|
{
|
|
int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT;
|
|
int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE;
|
|
|
|
stop_wakeup_tracer(tr);
|
|
/* make sure we put back any tasks we are tracing */
|
|
wakeup_reset(tr);
|
|
|
|
set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag);
|
|
set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag);
|
|
ftrace_reset_array_ops(tr);
|
|
wakeup_busy = false;
|
|
}
|
|
|
|
static void wakeup_tracer_start(struct trace_array *tr)
|
|
{
|
|
wakeup_reset(tr);
|
|
tracer_enabled = 1;
|
|
}
|
|
|
|
static void wakeup_tracer_stop(struct trace_array *tr)
|
|
{
|
|
tracer_enabled = 0;
|
|
}
|
|
|
|
static struct tracer wakeup_tracer __read_mostly =
|
|
{
|
|
.name = "wakeup",
|
|
.init = wakeup_tracer_init,
|
|
.reset = wakeup_tracer_reset,
|
|
.start = wakeup_tracer_start,
|
|
.stop = wakeup_tracer_stop,
|
|
.print_max = true,
|
|
.print_header = wakeup_print_header,
|
|
.print_line = wakeup_print_line,
|
|
.flag_changed = wakeup_flag_changed,
|
|
#ifdef CONFIG_FTRACE_SELFTEST
|
|
.selftest = trace_selftest_startup_wakeup,
|
|
#endif
|
|
.open = wakeup_trace_open,
|
|
.close = wakeup_trace_close,
|
|
.allow_instances = true,
|
|
.use_max_tr = true,
|
|
};
|
|
|
|
static struct tracer wakeup_rt_tracer __read_mostly =
|
|
{
|
|
.name = "wakeup_rt",
|
|
.init = wakeup_rt_tracer_init,
|
|
.reset = wakeup_tracer_reset,
|
|
.start = wakeup_tracer_start,
|
|
.stop = wakeup_tracer_stop,
|
|
.print_max = true,
|
|
.print_header = wakeup_print_header,
|
|
.print_line = wakeup_print_line,
|
|
.flag_changed = wakeup_flag_changed,
|
|
#ifdef CONFIG_FTRACE_SELFTEST
|
|
.selftest = trace_selftest_startup_wakeup,
|
|
#endif
|
|
.open = wakeup_trace_open,
|
|
.close = wakeup_trace_close,
|
|
.allow_instances = true,
|
|
.use_max_tr = true,
|
|
};
|
|
|
|
static struct tracer wakeup_dl_tracer __read_mostly =
|
|
{
|
|
.name = "wakeup_dl",
|
|
.init = wakeup_dl_tracer_init,
|
|
.reset = wakeup_tracer_reset,
|
|
.start = wakeup_tracer_start,
|
|
.stop = wakeup_tracer_stop,
|
|
.print_max = true,
|
|
.print_header = wakeup_print_header,
|
|
.print_line = wakeup_print_line,
|
|
.flag_changed = wakeup_flag_changed,
|
|
#ifdef CONFIG_FTRACE_SELFTEST
|
|
.selftest = trace_selftest_startup_wakeup,
|
|
#endif
|
|
.open = wakeup_trace_open,
|
|
.close = wakeup_trace_close,
|
|
.allow_instances = true,
|
|
.use_max_tr = true,
|
|
};
|
|
|
|
__init static int init_wakeup_tracer(void)
|
|
{
|
|
int ret;
|
|
|
|
ret = register_tracer(&wakeup_tracer);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = register_tracer(&wakeup_rt_tracer);
|
|
if (ret)
|
|
return ret;
|
|
|
|
ret = register_tracer(&wakeup_dl_tracer);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
core_initcall(init_wakeup_tracer);
|