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1// SPDX-License-Identifier: GPL-2.02/*3 * event tracer4 *5 * Copyright (C) 2022 Google Inc, Steven Rostedt <rostedt@goodmis.org>6 */7 8#define pr_fmt(fmt) fmt9 10#include <linux/trace_events.h>11#include <linux/module.h>12#include <linux/sched.h>13 14/*15 * Must include the event header that the custom event will attach to,16 * from the C file, and not in the custom header file.17 */18#include <trace/events/sched.h>19 20/* Declare CREATE_CUSTOM_TRACE_EVENTS before including custom header */21#define CREATE_CUSTOM_TRACE_EVENTS22 23#include "trace_custom_sched.h"24 25/*26 * As the trace events are not exported to modules, the use of27 * for_each_kernel_tracepoint() is needed to find the trace event28 * to attach to. The fct() function below, is a callback that29 * will be called for every event.30 *31 * Helper functions are created by the TRACE_CUSTOM_EVENT() macro32 * update the event. Those are of the form:33 *34 * trace_custom_event_<event>_update()35 *36 * Where <event> is the event to attach.37 */38static void fct(struct tracepoint *tp, void *priv)39{40 trace_custom_event_sched_switch_update(tp);41 trace_custom_event_sched_waking_update(tp);42}43 44static int __init trace_sched_init(void)45{46 for_each_kernel_tracepoint(fct, NULL);47 return 0;48}49 50static void __exit trace_sched_exit(void)51{52}53 54module_init(trace_sched_init);55module_exit(trace_sched_exit);56 57MODULE_AUTHOR("Steven Rostedt");58MODULE_DESCRIPTION("Custom scheduling events");59MODULE_LICENSE("GPL");60