sssw.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 "sssw"
 12
 13#include <trace/events/sched.h>
 14#include <trace/events/signal.h>
 15#include <rv_trace.h>
 16#include <monitors/sched/sched.h>
 17
 18#include "sssw.h"
 19
 20static struct rv_monitor rv_sssw;
 21DECLARE_DA_MON_PER_TASK(sssw, unsigned char);
 22
 23static void handle_sched_set_state(void *data, struct task_struct *tsk, int state)
 24{
 25	if (state == TASK_RUNNING)
 26		da_handle_start_event_sssw(tsk, sched_set_state_runnable_sssw);
 27	else
 28		da_handle_event_sssw(tsk, sched_set_state_sleepable_sssw);
 29}
 30
 31static void handle_sched_switch(void *data, bool preempt,
 32				struct task_struct *prev,
 33				struct task_struct *next,
 34				unsigned int prev_state)
 35{
 36	if (preempt)
 37		da_handle_event_sssw(prev, sched_switch_preempt_sssw);
 38	else if (prev_state == TASK_RUNNING)
 39		da_handle_event_sssw(prev, sched_switch_yield_sssw);
 40	else if (prev_state == TASK_RTLOCK_WAIT)
 41		/* special case of sleeping task with racy conditions */
 42		da_handle_event_sssw(prev, sched_switch_blocking_sssw);
 43	else
 44		da_handle_event_sssw(prev, sched_switch_suspend_sssw);
 45	da_handle_event_sssw(next, sched_switch_in_sssw);
 46}
 47
 48static void handle_sched_wakeup(void *data, struct task_struct *p)
 49{
 50	/*
 51	 * Wakeup can also lead to signal_wakeup although the system is
 52	 * actually runnable. The monitor can safely start with this event.
 53	 */
 54	da_handle_start_event_sssw(p, sched_wakeup_sssw);
 55}
 56
 57static void handle_signal_deliver(void *data, int sig,
 58				   struct kernel_siginfo *info,
 59				   struct k_sigaction *ka)
 60{
 61	da_handle_event_sssw(current, signal_deliver_sssw);
 62}
 63
 64static int enable_sssw(void)
 65{
 66	int retval;
 67
 68	retval = da_monitor_init_sssw();
 69	if (retval)
 70		return retval;
 71
 72	rv_attach_trace_probe("sssw", sched_set_state_tp, handle_sched_set_state);
 73	rv_attach_trace_probe("sssw", sched_switch, handle_sched_switch);
 74	rv_attach_trace_probe("sssw", sched_wakeup, handle_sched_wakeup);
 75	rv_attach_trace_probe("sssw", signal_deliver, handle_signal_deliver);
 76
 77	return 0;
 78}
 79
 80static void disable_sssw(void)
 81{
 82	rv_sssw.enabled = 0;
 83
 84	rv_detach_trace_probe("sssw", sched_set_state_tp, handle_sched_set_state);
 85	rv_detach_trace_probe("sssw", sched_switch, handle_sched_switch);
 86	rv_detach_trace_probe("sssw", sched_wakeup, handle_sched_wakeup);
 87	rv_detach_trace_probe("sssw", signal_deliver, handle_signal_deliver);
 88
 89	da_monitor_destroy_sssw();
 90}
 91
 92static struct rv_monitor rv_sssw = {
 93	.name = "sssw",
 94	.description = "set state sleep and wakeup.",
 95	.enable = enable_sssw,
 96	.disable = disable_sssw,
 97	.reset = da_monitor_reset_all_sssw,
 98	.enabled = 0,
 99};
100
101static int __init register_sssw(void)
102{
103	return rv_register_monitor(&rv_sssw, &rv_sched);
104}
105
106static void __exit unregister_sssw(void)
107{
108	rv_unregister_monitor(&rv_sssw);
109}
110
111module_init(register_sssw);
112module_exit(unregister_sssw);
113
114MODULE_LICENSE("GPL");
115MODULE_AUTHOR("Gabriele Monaco <gmonaco@redhat.com>");
116MODULE_DESCRIPTION("sssw: set state sleep and wakeup.");