--- /dev/null
+/*
+ * trace task wakeup timings
+ *
+ * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com>
+ * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com>
+ *
+ * Based on code from the latency_tracer, that is:
+ *
+ * Copyright (C) 2004-2006 Ingo Molnar
+ * Copyright (C) 2004 Nadia Yvette Chambers
+ */
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/uaccess.h>
+#include <linux/ftrace.h>
+#include <linux/sched/rt.h>
+#include <linux/sched/deadline.h>
+#include <trace/events/sched.h>
+#include "trace.h"
+
+static struct trace_array *wakeup_trace;
+static int __read_mostly tracer_enabled;
+
+static struct task_struct *wakeup_task;
+static int wakeup_cpu;
+static int wakeup_current_cpu;
+static unsigned wakeup_prio = -1;
+static int wakeup_rt;
+static int wakeup_dl;
+static int tracing_dl = 0;
+
+static arch_spinlock_t wakeup_lock =
+ (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED;
+
+static void wakeup_reset(struct trace_array *tr);
+static void __wakeup_reset(struct trace_array *tr);
+static int wakeup_graph_entry(struct ftrace_graph_ent *trace);
+static void wakeup_graph_return(struct ftrace_graph_ret *trace);
+
+static int save_flags;
+static bool function_enabled;
+
+#define TRACE_DISPLAY_GRAPH 1
+
+static struct tracer_opt trace_opts[] = {
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ /* display latency trace as call graph */
+ { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) },
+#endif
+ { } /* Empty entry */
+};
+
+static struct tracer_flags tracer_flags = {
+ .val = 0,
+ .opts = trace_opts,
+};
+
+#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH)
+
+#ifdef CONFIG_FUNCTION_TRACER
+
+/*
+ * Prologue for the wakeup function tracers.
+ *
+ * Returns 1 if it is OK to continue, and preemption
+ * is disabled and data->disabled is incremented.
+ * 0 if the trace is to be ignored, and preemption
+ * is not disabled and data->disabled is
+ * kept the same.
+ *
+ * Note, this function is also used outside this ifdef but
+ * inside the #ifdef of the function graph tracer below.
+ * This is OK, since the function graph tracer is
+ * dependent on the function tracer.
+ */
+static int
+func_prolog_preempt_disable(struct trace_array *tr,
+ struct trace_array_cpu **data,
+ int *pc)
+{
+ long disabled;
+ int cpu;
+
+ if (likely(!wakeup_task))
+ return 0;
+
+ *pc = preempt_count();
+ preempt_disable_notrace();
+
+ cpu = raw_smp_processor_id();
+ if (cpu != wakeup_current_cpu)
+ goto out_enable;
+
+ *data = per_cpu_ptr(tr->trace_buffer.data, cpu);
+ disabled = atomic_inc_return(&(*data)->disabled);
+ if (unlikely(disabled != 1))
+ goto out;
+
+ return 1;
+
+out:
+ atomic_dec(&(*data)->disabled);
+
+out_enable:
+ preempt_enable_notrace();
+ return 0;
+}
+
+/*
+ * wakeup uses its own tracer function to keep the overhead down:
+ */
+static void
+wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
+{
+ struct trace_array *tr = wakeup_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ int pc;
+
+ if (!func_prolog_preempt_disable(tr, &data, &pc))
+ return;
+
+ local_irq_save(flags);
+ trace_function(tr, ip, parent_ip, flags, pc);
+ local_irq_restore(flags);
+
+ atomic_dec(&data->disabled);
+ preempt_enable_notrace();
+}
+#endif /* CONFIG_FUNCTION_TRACER */
+
+static int register_wakeup_function(struct trace_array *tr, int graph, int set)
+{
+ int ret;
+
+ /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */
+ if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION)))
+ return 0;
+
+ if (graph)
+ ret = register_ftrace_graph(&wakeup_graph_return,
+ &wakeup_graph_entry);
+ else
+ ret = register_ftrace_function(tr->ops);
+
+ if (!ret)
+ function_enabled = true;
+
+ return ret;
+}
+
+static void unregister_wakeup_function(struct trace_array *tr, int graph)
+{
+ if (!function_enabled)
+ return;
+
+ if (graph)
+ unregister_ftrace_graph();
+ else
+ unregister_ftrace_function(tr->ops);
+
+ function_enabled = false;
+}
+
+static void wakeup_function_set(struct trace_array *tr, int set)
+{
+ if (set)
+ register_wakeup_function(tr, is_graph(), 1);
+ else
+ unregister_wakeup_function(tr, is_graph());
+}
+
+static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set)
+{
+ struct tracer *tracer = tr->current_trace;
+
+ if (mask & TRACE_ITER_FUNCTION)
+ wakeup_function_set(tr, set);
+
+ return trace_keep_overwrite(tracer, mask, set);
+}
+
+static int start_func_tracer(struct trace_array *tr, int graph)
+{
+ int ret;
+
+ ret = register_wakeup_function(tr, graph, 0);
+
+ if (!ret && tracing_is_enabled())
+ tracer_enabled = 1;
+ else
+ tracer_enabled = 0;
+
+ return ret;
+}
+
+static void stop_func_tracer(struct trace_array *tr, int graph)
+{
+ tracer_enabled = 0;
+
+ unregister_wakeup_function(tr, graph);
+}
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+static int
+wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
+{
+
+ if (!(bit & TRACE_DISPLAY_GRAPH))
+ return -EINVAL;
+
+ if (!(is_graph() ^ set))
+ return 0;
+
+ stop_func_tracer(tr, !set);
+
+ wakeup_reset(wakeup_trace);
+ tr->max_latency = 0;
+
+ return start_func_tracer(tr, set);
+}
+
+static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
+{
+ struct trace_array *tr = wakeup_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ int pc, ret = 0;
+
+ if (!func_prolog_preempt_disable(tr, &data, &pc))
+ return 0;
+
+ local_save_flags(flags);
+ ret = __trace_graph_entry(tr, trace, flags, pc);
+ atomic_dec(&data->disabled);
+ preempt_enable_notrace();
+
+ return ret;
+}
+
+static void wakeup_graph_return(struct ftrace_graph_ret *trace)
+{
+ struct trace_array *tr = wakeup_trace;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ int pc;
+
+ if (!func_prolog_preempt_disable(tr, &data, &pc))
+ return;
+
+ local_save_flags(flags);
+ __trace_graph_return(tr, trace, flags, pc);
+ atomic_dec(&data->disabled);
+
+ preempt_enable_notrace();
+ return;
+}
+
+static void wakeup_trace_open(struct trace_iterator *iter)
+{
+ if (is_graph())
+ graph_trace_open(iter);
+}
+
+static void wakeup_trace_close(struct trace_iterator *iter)
+{
+ if (iter->private)
+ graph_trace_close(iter);
+}
+
+#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_PROC | \
+ TRACE_GRAPH_PRINT_ABS_TIME | \
+ TRACE_GRAPH_PRINT_DURATION)
+
+static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
+{
+ /*
+ * In graph mode call the graph tracer output function,
+ * otherwise go with the TRACE_FN event handler
+ */
+ if (is_graph())
+ return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS);
+
+ return TRACE_TYPE_UNHANDLED;
+}
+
+static void wakeup_print_header(struct seq_file *s)
+{
+ if (is_graph())
+ print_graph_headers_flags(s, GRAPH_TRACER_FLAGS);
+ else
+ trace_default_header(s);
+}
+
+static void
+__trace_function(struct trace_array *tr,
+ unsigned long ip, unsigned long parent_ip,
+ unsigned long flags, int pc)
+{
+ if (is_graph())
+ trace_graph_function(tr, ip, parent_ip, flags, pc);
+ else
+ trace_function(tr, ip, parent_ip, flags, pc);
+}
+#else
+#define __trace_function trace_function
+
+static int
+wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set)
+{
+ return -EINVAL;
+}
+
+static int wakeup_graph_entry(struct ftrace_graph_ent *trace)
+{
+ return -1;
+}
+
+static enum print_line_t wakeup_print_line(struct trace_iterator *iter)
+{
+ return TRACE_TYPE_UNHANDLED;
+}
+
+static void wakeup_graph_return(struct ftrace_graph_ret *trace) { }
+static void wakeup_trace_open(struct trace_iterator *iter) { }
+static void wakeup_trace_close(struct trace_iterator *iter) { }
+
+#ifdef CONFIG_FUNCTION_TRACER
+static void wakeup_print_header(struct seq_file *s)
+{
+ trace_default_header(s);
+}
+#else
+static void wakeup_print_header(struct seq_file *s)
+{
+ trace_latency_header(s);
+}
+#endif /* CONFIG_FUNCTION_TRACER */
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+/*
+ * Should this new latency be reported/recorded?
+ */
+static int report_latency(struct trace_array *tr, cycle_t delta)
+{
+ if (tracing_thresh) {
+ if (delta < tracing_thresh)
+ return 0;
+ } else {
+ if (delta <= tr->max_latency)
+ return 0;
+ }
+ return 1;
+}
+
+static void
+probe_wakeup_migrate_task(void *ignore, struct task_struct *task, int cpu)
+{
+ if (task != wakeup_task)
+ return;
+
+ wakeup_current_cpu = cpu;
+}
+
+static void
+tracing_sched_switch_trace(struct trace_array *tr,
+ struct task_struct *prev,
+ struct task_struct *next,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_context_switch;
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_CTX,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = prev->pid;
+ entry->prev_prio = prev->prio;
+ entry->prev_state = prev->state;
+ entry->next_pid = next->pid;
+ entry->next_prio = next->prio;
+ entry->next_state = next->state;
+ entry->next_cpu = task_cpu(next);
+
+ if (!call_filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, flags, pc);
+}
+
+static void
+tracing_sched_wakeup_trace(struct trace_array *tr,
+ struct task_struct *wakee,
+ struct task_struct *curr,
+ unsigned long flags, int pc)
+{
+ struct ftrace_event_call *call = &event_wakeup;
+ struct ring_buffer_event *event;
+ struct ctx_switch_entry *entry;
+ struct ring_buffer *buffer = tr->trace_buffer.buffer;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_WAKE,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->prev_pid = curr->pid;
+ entry->prev_prio = curr->prio;
+ entry->prev_state = curr->state;
+ entry->next_pid = wakee->pid;
+ entry->next_prio = wakee->prio;
+ entry->next_state = wakee->state;
+ entry->next_cpu = task_cpu(wakee);
+
+ if (!call_filter_check_discard(call, entry, buffer, event))
+ trace_buffer_unlock_commit(buffer, event, flags, pc);
+}
+
+static void notrace
+probe_wakeup_sched_switch(void *ignore,
+ struct task_struct *prev, struct task_struct *next)
+{
+ struct trace_array_cpu *data;
+ cycle_t T0, T1, delta;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ tracing_record_cmdline(prev);
+
+ if (unlikely(!tracer_enabled))
+ return;
+
+ /*
+ * When we start a new trace, we set wakeup_task to NULL
+ * and then set tracer_enabled = 1. We want to make sure
+ * that another CPU does not see the tracer_enabled = 1
+ * and the wakeup_task with an older task, that might
+ * actually be the same as next.
+ */
+ smp_rmb();
+
+ if (next != wakeup_task)
+ return;
+
+ pc = preempt_count();
+
+ /* disable local data, not wakeup_cpu data */
+ cpu = raw_smp_processor_id();
+ disabled = atomic_inc_return(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
+ if (likely(disabled != 1))
+ goto out;
+
+ local_irq_save(flags);
+ arch_spin_lock(&wakeup_lock);
+
+ /* We could race with grabbing wakeup_lock */
+ if (unlikely(!tracer_enabled || next != wakeup_task))
+ goto out_unlock;
+
+ /* The task we are waiting for is waking up */
+ data = per_cpu_ptr(wakeup_trace->trace_buffer.data, wakeup_cpu);
+
+ __trace_function(wakeup_trace, CALLER_ADDR0, CALLER_ADDR1, flags, pc);
+ tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
+
+ T0 = data->preempt_timestamp;
+ T1 = ftrace_now(cpu);
+ delta = T1-T0;
+
+ if (!report_latency(wakeup_trace, delta))
+ goto out_unlock;
+
+ if (likely(!is_tracing_stopped())) {
+ wakeup_trace->max_latency = delta;
+ update_max_tr(wakeup_trace, wakeup_task, wakeup_cpu);
+ }
+
+out_unlock:
+ __wakeup_reset(wakeup_trace);
+ arch_spin_unlock(&wakeup_lock);
+ local_irq_restore(flags);
+out:
+ atomic_dec(&per_cpu_ptr(wakeup_trace->trace_buffer.data, cpu)->disabled);
+}
+
+static void __wakeup_reset(struct trace_array *tr)
+{
+ wakeup_cpu = -1;
+ wakeup_prio = -1;
+ tracing_dl = 0;
+
+ if (wakeup_task)
+ put_task_struct(wakeup_task);
+
+ wakeup_task = NULL;
+}
+
+static void wakeup_reset(struct trace_array *tr)
+{
+ unsigned long flags;
+
+ tracing_reset_online_cpus(&tr->trace_buffer);
+
+ local_irq_save(flags);
+ arch_spin_lock(&wakeup_lock);
+ __wakeup_reset(tr);
+ arch_spin_unlock(&wakeup_lock);
+ local_irq_restore(flags);
+}
+
+static void
+probe_wakeup(void *ignore, struct task_struct *p, int success)
+{
+ struct trace_array_cpu *data;
+ int cpu = smp_processor_id();
+ unsigned long flags;
+ long disabled;
+ int pc;
+
+ if (likely(!tracer_enabled))
+ return;
+
+ tracing_record_cmdline(p);
+ tracing_record_cmdline(current);
+
+ /*
+ * 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()))
+ 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());
+ 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 = 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,
+ .flags = &tracer_flags,
+ .set_flag = wakeup_set_flag,
+ .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,
+ .flags = &tracer_flags,
+ .set_flag = wakeup_set_flag,
+ .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,
+ .flags = &tracer_flags,
+ .set_flag = wakeup_set_flag,
+ .flag_changed = wakeup_flag_changed,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_wakeup,
+#endif
+ .open = wakeup_trace_open,
+ .close = wakeup_trace_close,
+ .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);
Code Review / kvmfornfv.git / blobdiff