linux_dsm_epyc7002/include/linux/nmi.h
Nicholas Piggin 05a4a95279 kernel/watchdog: split up config options
Split SOFTLOCKUP_DETECTOR from LOCKUP_DETECTOR, and split
HARDLOCKUP_DETECTOR_PERF from HARDLOCKUP_DETECTOR.

LOCKUP_DETECTOR implies the general boot, sysctl, and programming
interfaces for the lockup detectors.

An architecture that wants to use a hard lockup detector must define
HAVE_HARDLOCKUP_DETECTOR_PERF or HAVE_HARDLOCKUP_DETECTOR_ARCH.

Alternatively an arch can define HAVE_NMI_WATCHDOG, which provides the
minimum arch_touch_nmi_watchdog, and it otherwise does its own thing and
does not implement the LOCKUP_DETECTOR interfaces.

sparc is unusual in that it has started to implement some of the
interfaces, but not fully yet.  It should probably be converted to a full
HAVE_HARDLOCKUP_DETECTOR_ARCH.

[npiggin@gmail.com: fix]
  Link: http://lkml.kernel.org/r/20170617223522.66c0ad88@roar.ozlabs.ibm.com
Link: http://lkml.kernel.org/r/20170616065715.18390-4-npiggin@gmail.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Don Zickus <dzickus@redhat.com>
Reviewed-by: Babu Moger <babu.moger@oracle.com>
Tested-by: Babu Moger <babu.moger@oracle.com>	[sparc]
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-12 16:26:02 -07:00

201 lines
5.3 KiB
C

/*
* linux/include/linux/nmi.h
*/
#ifndef LINUX_NMI_H
#define LINUX_NMI_H
#include <linux/sched.h>
#include <asm/irq.h>
#if defined(CONFIG_HAVE_NMI_WATCHDOG)
#include <asm/nmi.h>
#endif
#ifdef CONFIG_LOCKUP_DETECTOR
void lockup_detector_init(void);
#else
static inline void lockup_detector_init(void)
{
}
#endif
#ifdef CONFIG_SOFTLOCKUP_DETECTOR
extern void touch_softlockup_watchdog_sched(void);
extern void touch_softlockup_watchdog(void);
extern void touch_softlockup_watchdog_sync(void);
extern void touch_all_softlockup_watchdogs(void);
extern unsigned int softlockup_panic;
extern int soft_watchdog_enabled;
extern atomic_t watchdog_park_in_progress;
#else
static inline void touch_softlockup_watchdog_sched(void)
{
}
static inline void touch_softlockup_watchdog(void)
{
}
static inline void touch_softlockup_watchdog_sync(void)
{
}
static inline void touch_all_softlockup_watchdogs(void)
{
}
#endif
#ifdef CONFIG_DETECT_HUNG_TASK
void reset_hung_task_detector(void);
#else
static inline void reset_hung_task_detector(void)
{
}
#endif
/*
* The run state of the lockup detectors is controlled by the content of the
* 'watchdog_enabled' variable. Each lockup detector has its dedicated bit -
* bit 0 for the hard lockup detector and bit 1 for the soft lockup detector.
*
* 'watchdog_user_enabled', 'nmi_watchdog_enabled' and 'soft_watchdog_enabled'
* are variables that are only used as an 'interface' between the parameters
* in /proc/sys/kernel and the internal state bits in 'watchdog_enabled'. The
* 'watchdog_thresh' variable is handled differently because its value is not
* boolean, and the lockup detectors are 'suspended' while 'watchdog_thresh'
* is equal zero.
*/
#define NMI_WATCHDOG_ENABLED_BIT 0
#define SOFT_WATCHDOG_ENABLED_BIT 1
#define NMI_WATCHDOG_ENABLED (1 << NMI_WATCHDOG_ENABLED_BIT)
#define SOFT_WATCHDOG_ENABLED (1 << SOFT_WATCHDOG_ENABLED_BIT)
#if defined(CONFIG_HARDLOCKUP_DETECTOR)
extern void hardlockup_detector_disable(void);
extern unsigned int hardlockup_panic;
#else
static inline void hardlockup_detector_disable(void) {}
#endif
#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)
extern void arch_touch_nmi_watchdog(void);
#else
#if !defined(CONFIG_HAVE_NMI_WATCHDOG)
static inline void arch_touch_nmi_watchdog(void) {}
#endif
#endif
/**
* touch_nmi_watchdog - restart NMI watchdog timeout.
*
* If the architecture supports the NMI watchdog, touch_nmi_watchdog()
* may be used to reset the timeout - for code which intentionally
* disables interrupts for a long time. This call is stateless.
*/
static inline void touch_nmi_watchdog(void)
{
arch_touch_nmi_watchdog();
touch_softlockup_watchdog();
}
/*
* Create trigger_all_cpu_backtrace() out of the arch-provided
* base function. Return whether such support was available,
* to allow calling code to fall back to some other mechanism:
*/
#ifdef arch_trigger_cpumask_backtrace
static inline bool trigger_all_cpu_backtrace(void)
{
arch_trigger_cpumask_backtrace(cpu_online_mask, false);
return true;
}
static inline bool trigger_allbutself_cpu_backtrace(void)
{
arch_trigger_cpumask_backtrace(cpu_online_mask, true);
return true;
}
static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
{
arch_trigger_cpumask_backtrace(mask, false);
return true;
}
static inline bool trigger_single_cpu_backtrace(int cpu)
{
arch_trigger_cpumask_backtrace(cpumask_of(cpu), false);
return true;
}
/* generic implementation */
void nmi_trigger_cpumask_backtrace(const cpumask_t *mask,
bool exclude_self,
void (*raise)(cpumask_t *mask));
bool nmi_cpu_backtrace(struct pt_regs *regs);
#else
static inline bool trigger_all_cpu_backtrace(void)
{
return false;
}
static inline bool trigger_allbutself_cpu_backtrace(void)
{
return false;
}
static inline bool trigger_cpumask_backtrace(struct cpumask *mask)
{
return false;
}
static inline bool trigger_single_cpu_backtrace(int cpu)
{
return false;
}
#endif
#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF
u64 hw_nmi_get_sample_period(int watchdog_thresh);
#endif
#ifdef CONFIG_LOCKUP_DETECTOR
extern int nmi_watchdog_enabled;
extern int watchdog_user_enabled;
extern int watchdog_thresh;
extern unsigned long watchdog_enabled;
extern struct cpumask watchdog_cpumask;
extern unsigned long *watchdog_cpumask_bits;
extern int __read_mostly watchdog_suspended;
#ifdef CONFIG_SMP
extern int sysctl_softlockup_all_cpu_backtrace;
extern int sysctl_hardlockup_all_cpu_backtrace;
#else
#define sysctl_softlockup_all_cpu_backtrace 0
#define sysctl_hardlockup_all_cpu_backtrace 0
#endif
extern bool is_hardlockup(void);
struct ctl_table;
extern int proc_watchdog(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
extern int proc_nmi_watchdog(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
extern int proc_soft_watchdog(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
extern int proc_watchdog_thresh(struct ctl_table *, int ,
void __user *, size_t *, loff_t *);
extern int proc_watchdog_cpumask(struct ctl_table *, int,
void __user *, size_t *, loff_t *);
extern int lockup_detector_suspend(void);
extern void lockup_detector_resume(void);
#else
static inline int lockup_detector_suspend(void)
{
return 0;
}
static inline void lockup_detector_resume(void)
{
}
#endif
#ifdef CONFIG_HAVE_ACPI_APEI_NMI
#include <asm/nmi.h>
#endif
#endif