1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * latencytop.h: Infrastructure for displaying latency
4 *
5 * (C) Copyright 2008 Intel Corporation
6 * Author: Arjan van de Ven <arjan@linux.intel.com>
7 *
8 */
9
10#ifndef _INCLUDE_GUARD_LATENCYTOP_H_
11#define _INCLUDE_GUARD_LATENCYTOP_H_
12
13#include <linux/compiler.h>
14struct task_struct;
15
16#ifdef CONFIG_LATENCYTOP
17
18#define LT_SAVECOUNT 32
19#define LT_BACKTRACEDEPTH 12
20
21struct latency_record {
22 unsigned long backtrace[LT_BACKTRACEDEPTH];
23 unsigned int count;
24 unsigned long time;
25 unsigned long max;
26};
27
28
29
30extern int latencytop_enabled;
31void __account_scheduler_latency(struct task_struct *task, int usecs, int inter);
32static inline void
33account_scheduler_latency(struct task_struct *task, int usecs, int inter)
34{
35 if (unlikely(latencytop_enabled))
36 __account_scheduler_latency(task, usecs, inter);
37}
38
39void clear_tsk_latency_tracing(struct task_struct *p);
40
41#else
42
43static inline void
44account_scheduler_latency(struct task_struct *task, int usecs, int inter)
45{
46}
47
48static inline void clear_tsk_latency_tracing(struct task_struct *p)
49{
50}
51
52#endif
53
54#endif
55

source code of linux/include/linux/latencytop.h