Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * linux/include/linux/nmi.h
3 */
4#ifndef LINUX_NMI_H
5#define LINUX_NMI_H
6
7#include <linux/sched.h>
8#include <asm/irq.h>
9#if defined(CONFIG_HAVE_NMI_WATCHDOG)
10#include <asm/nmi.h>
11#endif
12
13#ifdef CONFIG_LOCKUP_DETECTOR
14void lockup_detector_init(void);
15#else
16static inline void lockup_detector_init(void)
17{
18}
19#endif
20
21#ifdef CONFIG_SOFTLOCKUP_DETECTOR
22extern void touch_softlockup_watchdog_sched(void);
23extern void touch_softlockup_watchdog(void);
24extern void touch_softlockup_watchdog_sync(void);
25extern void touch_all_softlockup_watchdogs(void);
26extern unsigned int softlockup_panic;
27extern int soft_watchdog_enabled;
28extern atomic_t watchdog_park_in_progress;
29#else
30static inline void touch_softlockup_watchdog_sched(void)
31{
32}
33static inline void touch_softlockup_watchdog(void)
34{
35}
36static inline void touch_softlockup_watchdog_sync(void)
37{
38}
39static inline void touch_all_softlockup_watchdogs(void)
40{
41}
42#endif
43
44#ifdef CONFIG_DETECT_HUNG_TASK
45void reset_hung_task_detector(void);
46#else
47static inline void reset_hung_task_detector(void)
48{
49}
50#endif
51
52/*
53 * The run state of the lockup detectors is controlled by the content of the
54 * 'watchdog_enabled' variable. Each lockup detector has its dedicated bit -
55 * bit 0 for the hard lockup detector and bit 1 for the soft lockup detector.
56 *
57 * 'watchdog_user_enabled', 'nmi_watchdog_enabled' and 'soft_watchdog_enabled'
58 * are variables that are only used as an 'interface' between the parameters
59 * in /proc/sys/kernel and the internal state bits in 'watchdog_enabled'. The
60 * 'watchdog_thresh' variable is handled differently because its value is not
61 * boolean, and the lockup detectors are 'suspended' while 'watchdog_thresh'
62 * is equal zero.
63 */
64#define NMI_WATCHDOG_ENABLED_BIT 0
65#define SOFT_WATCHDOG_ENABLED_BIT 1
66#define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT)
67#define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT)
68
69#if defined(CONFIG_HARDLOCKUP_DETECTOR)
70extern void hardlockup_detector_disable(void);
71extern unsigned int hardlockup_panic;
72#else
73static inline void hardlockup_detector_disable(void) {}
74#endif
75
76#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
77extern void arch_touch_nmi_watchdog(void);
78#else
79#if !defined(CONFIG_HAVE_NMI_WATCHDOG)
80static inline void arch_touch_nmi_watchdog(void) {}
81#endif
82#endif
83
84/**
85 * touch_nmi_watchdog - restart NMI watchdog timeout.
86 *
87 * If the architecture supports the NMI watchdog, touch_nmi_watchdog()
88 * may be used to reset the timeout - for code which intentionally
89 * disables interrupts for a long time. This call is stateless.
90 */
91static inline void touch_nmi_watchdog(void)
92{
93 arch_touch_nmi_watchdog();
94 touch_softlockup_watchdog();
95}
96
97/*
98 * Create trigger_all_cpu_backtrace() out of the arch-provided
99 * base function. Return whether such support was available,
100 * to allow calling code to fall back to some other mechanism:
101 */
102#ifdef arch_trigger_cpumask_backtrace
103static inline bool trigger_all_cpu_backtrace(void)
104{
105 arch_trigger_cpumask_backtrace(cpu_online_mask, false);
106 return true;
107}
108
109static inline bool trigger_allbutself_cpu_backtrace(void)
110{
111 arch_trigger_cpumask_backtrace(cpu_online_mask, true);
112 return true;
113}
114
115static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
116{
117 arch_trigger_cpumask_backtrace(mask, false);
118 return true;
119}
120
121static inline bool trigger_single_cpu_backtrace(int cpu)
122{
123 arch_trigger_cpumask_backtrace(cpumask_of(cpu), false);
124 return true;
125}
126
127/* generic implementation */
128void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
129 bool exclude_self,
130 void (*raise)(cpumask_t *mask));
131bool nmi_cpu_backtrace(struct pt_regs *regs);
132
133#else
134static inline bool trigger_all_cpu_backtrace(void)
135{
136 return false;
137}
138static inline bool trigger_allbutself_cpu_backtrace(void)
139{
140 return false;
141}
142static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
143{
144 return false;
145}
146static inline bool trigger_single_cpu_backtrace(int cpu)
147{
148 return false;
149}
150#endif
151
152#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
153u64 hw_nmi_get_sample_period(int watchdog_thresh);
154#endif
155
156#ifdef CONFIG_LOCKUP_DETECTOR
157extern int nmi_watchdog_enabled;
158extern int watchdog_user_enabled;
159extern int watchdog_thresh;
160extern unsigned long watchdog_enabled;
161extern struct cpumask watchdog_cpumask;
162extern unsigned long *watchdog_cpumask_bits;
163extern int __read_mostly watchdog_suspended;
164#ifdef CONFIG_SMP
165extern int sysctl_softlockup_all_cpu_backtrace;
166extern int sysctl_hardlockup_all_cpu_backtrace;
167#else
168#define sysctl_softlockup_all_cpu_backtrace 0
169#define sysctl_hardlockup_all_cpu_backtrace 0
170#endif
171
172#if defined(CONFIG_HARDLOCKUP_CHECK_TIMESTAMP) && \
173 defined(CONFIG_HARDLOCKUP_DETECTOR)
174void watchdog_update_hrtimer_threshold(u64 period);
175#else
176static inline void watchdog_update_hrtimer_threshold(u64 period) { }
177#endif
178
179extern bool is_hardlockup(void);
180struct ctl_table;
181extern int proc_watchdog(struct ctl_table *, int ,
182 void __user *, size_t *, loff_t *);
183extern int proc_nmi_watchdog(struct ctl_table *, int ,
184 void __user *, size_t *, loff_t *);
185extern int proc_soft_watchdog(struct ctl_table *, int ,
186 void __user *, size_t *, loff_t *);
187extern int proc_watchdog_thresh(struct ctl_table *, int ,
188 void __user *, size_t *, loff_t *);
189extern int proc_watchdog_cpumask(struct ctl_table *, int,
190 void __user *, size_t *, loff_t *);
191extern int lockup_detector_suspend(void);
192extern void lockup_detector_resume(void);
193#else
194static inline int lockup_detector_suspend(void)
195{
196 return 0;
197}
198
199static inline void lockup_detector_resume(void)
200{
201}
202#endif
203
204#ifdef CONFIG_HAVE_ACPI_APEI_NMI
205#include <asm/nmi.h>
206#endif
207
208#endif