scpd.c

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/ftrace.h>
 3#include <linux/tracepoint.h>
 4#include <linux/kernel.h>
 5#include <linux/module.h>
 6#include <linux/init.h>
 7#include <linux/rv.h>
 8#include <rv/instrumentation.h>
 9#include <rv/da_monitor.h>
10
11#define MODULE_NAME "scpd"
12
13#include <trace/events/sched.h>
14#include <trace/events/preemptirq.h>
15#include <rv_trace.h>
16#include <monitors/sched/sched.h>
17
18#include "scpd.h"
19
20static struct rv_monitor rv_scpd;
21DECLARE_DA_MON_PER_CPU(scpd, unsigned char);
22
23static void handle_preempt_disable(void *data, unsigned long ip, unsigned long parent_ip)
24{
25	da_handle_event_scpd(preempt_disable_scpd);
26}
27
28static void handle_preempt_enable(void *data, unsigned long ip, unsigned long parent_ip)
29{
30	da_handle_start_event_scpd(preempt_enable_scpd);
31}
32
33static void handle_schedule_entry(void *data, bool preempt)
34{
35	da_handle_event_scpd(schedule_entry_scpd);
36}
37
38static void handle_schedule_exit(void *data, bool is_switch)
39{
40	da_handle_event_scpd(schedule_exit_scpd);
41}
42
43static int enable_scpd(void)
44{
45	int retval;
46
47	retval = da_monitor_init_scpd();
48	if (retval)
49		return retval;
50
51	rv_attach_trace_probe("scpd", preempt_disable, handle_preempt_disable);
52	rv_attach_trace_probe("scpd", preempt_enable, handle_preempt_enable);
53	rv_attach_trace_probe("scpd", sched_entry_tp, handle_schedule_entry);
54	rv_attach_trace_probe("scpd", sched_exit_tp, handle_schedule_exit);
55
56	return 0;
57}
58
59static void disable_scpd(void)
60{
61	rv_scpd.enabled = 0;
62
63	rv_detach_trace_probe("scpd", preempt_disable, handle_preempt_disable);
64	rv_detach_trace_probe("scpd", preempt_enable, handle_preempt_enable);
65	rv_detach_trace_probe("scpd", sched_entry_tp, handle_schedule_entry);
66	rv_detach_trace_probe("scpd", sched_exit_tp, handle_schedule_exit);
67
68	da_monitor_destroy_scpd();
69}
70
71static struct rv_monitor rv_scpd = {
72	.name = "scpd",
73	.description = "schedule called with preemption disabled.",
74	.enable = enable_scpd,
75	.disable = disable_scpd,
76	.reset = da_monitor_reset_all_scpd,
77	.enabled = 0,
78};
79
80static int __init register_scpd(void)
81{
82	return rv_register_monitor(&rv_scpd, &rv_sched);
83}
84
85static void __exit unregister_scpd(void)
86{
87	rv_unregister_monitor(&rv_scpd);
88}
89
90module_init(register_scpd);
91module_exit(unregister_scpd);
92
93MODULE_LICENSE("GPL");
94MODULE_AUTHOR("Gabriele Monaco <gmonaco@redhat.com>");
95MODULE_DESCRIPTION("scpd: schedule called with preemption disabled.");