diff options
Diffstat (limited to 'samples/trace_events/trace_custom_sched.c')
-rw-r--r-- | samples/trace_events/trace_custom_sched.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/samples/trace_events/trace_custom_sched.c b/samples/trace_events/trace_custom_sched.c new file mode 100644 index 000000000..b99d9ab7d --- /dev/null +++ b/samples/trace_events/trace_custom_sched.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * event tracer + * + * Copyright (C) 2022 Google Inc, Steven Rostedt <rostedt@goodmis.org> + */ + +#define pr_fmt(fmt) fmt + +#include <linux/trace_events.h> +#include <linux/version.h> +#include <linux/module.h> +#include <linux/sched.h> + +/* + * Must include the event header that the custom event will attach to, + * from the C file, and not in the custom header file. + */ +#include <trace/events/sched.h> + +/* Declare CREATE_CUSTOM_TRACE_EVENTS before including custom header */ +#define CREATE_CUSTOM_TRACE_EVENTS + +#include "trace_custom_sched.h" + +/* + * As the trace events are not exported to modules, the use of + * for_each_kernel_tracepoint() is needed to find the trace event + * to attach to. The fct() function below, is a callback that + * will be called for every event. + * + * Helper functions are created by the TRACE_CUSTOM_EVENT() macro + * update the event. Those are of the form: + * + * trace_custom_event_<event>_update() + * + * Where <event> is the event to attach. + */ +static void fct(struct tracepoint *tp, void *priv) +{ + trace_custom_event_sched_switch_update(tp); + trace_custom_event_sched_waking_update(tp); +} + +static int __init trace_sched_init(void) +{ + for_each_kernel_tracepoint(fct, NULL); + return 0; +} + +static void __exit trace_sched_exit(void) +{ +} + +module_init(trace_sched_init); +module_exit(trace_sched_exit); + +MODULE_AUTHOR("Steven Rostedt"); +MODULE_DESCRIPTION("Custom scheduling events"); +MODULE_LICENSE("GPL"); |