Commit 4ffed7d5 authored by Xiongfeng Wang's avatar Xiongfeng Wang Committed by Zheng Zengkai
Browse files

watchdog: make hardlockup detect code public 



hulk inclusion
category: feature
bugzilla: 48046
CVE: NA

-------------------------------------------------------------------------

In current code, the hardlockup detect code is contained by
CONFIG_HARDLOCKUP_DETECTOR_PERF. This patch makes this code public so
that other arch hardlockup detector can use it.

Signed-off-by: default avatarXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarYang Yingliang <yangyingliang@huawei.com>
Signed-off-by: default avatarXiongfeng Wang <wangxiongfeng2@huawei.com>
Reviewed-by: default avatarHanjun Guo <guohanjun@huawei.com>
Signed-off-by: default avatarZheng Zengkai <zhengzengkai@huawei.com>
parent ea9c6286

include/linux/nmi.h

+12 −3
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 


#include <linux/sched.h>

#include <asm/irq.h>

#if defined(CONFIG_HAVE_NMI_WATCHDOG)

#if defined(CONFIG_HAVE_NMI_WATCHDOG) && !defined(CONFIG_SDEI_WATCHDOG)

#include <asm/nmi.h>

#endif
@@ -83,6 +83,7 @@ static inline void reset_hung_task_detector(void) { } 


#if defined(CONFIG_HARDLOCKUP_DETECTOR)

extern void hardlockup_detector_disable(void);

extern void watchdog_hardlockup_check(struct pt_regs *regs);

extern unsigned int hardlockup_panic;

#else

static inline void hardlockup_detector_disable(void) {}
@@ -94,8 +95,17 @@ static inline void hardlockup_detector_disable(void) {} 
# define NMI_WATCHDOG_SYSCTL_PERM	0444

#endif



#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)

#if defined(CONFIG_HARDLOCKUP_DETECTOR)

#ifndef CONFIG_PPC

extern void arch_touch_nmi_watchdog(void);

#endif

#else

# if !defined(CONFIG_HAVE_NMI_WATCHDOG)

static inline void arch_touch_nmi_watchdog(void) {}

# endif

#endif



#if defined(CONFIG_HARDLOCKUP_DETECTOR_PERF)

extern void hardlockup_detector_perf_stop(void);

extern void hardlockup_detector_perf_restart(void);

extern void hardlockup_detector_perf_disable(void);
@@ -110,7 +120,6 @@ static inline void hardlockup_detector_perf_enable(void) { } 
static inline void hardlockup_detector_perf_cleanup(void) { }

# if !defined(CONFIG_HAVE_NMI_WATCHDOG)

static inline int hardlockup_detector_perf_init(void) { return -ENODEV; }

static inline void arch_touch_nmi_watchdog(void) {}

# else

static inline int hardlockup_detector_perf_init(void) { return 0; }

# endif

kernel/Makefile

+1 −1
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ obj-$(CONFIG_FAIL_FUNCTION) += fail_function.o 
obj-$(CONFIG_KGDB) += debug/

obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o

obj-$(CONFIG_LOCKUP_DETECTOR) += watchdog.o

obj-$(CONFIG_HARDLOCKUP_DETECTOR_PERF) += watchdog_hld.o

obj-$(CONFIG_HARDLOCKUP_DETECTOR) += watchdog_hld.o

obj-$(CONFIG_SECCOMP) += seccomp.o

obj-$(CONFIG_RELAY) += relay.o

obj-$(CONFIG_SYSCTL) += utsname_sysctl.o

kernel/watchdog_hld.c

+30 −20
Original line number Diff line number Diff line
@@ -22,14 +22,11 @@ 


static DEFINE_PER_CPU(bool, hard_watchdog_warn);

static DEFINE_PER_CPU(bool, watchdog_nmi_touch);

static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);

static DEFINE_PER_CPU(struct perf_event *, dead_event);

static struct cpumask dead_events_mask;



static unsigned long hardlockup_allcpu_dumped;

static atomic_t watchdog_cpus = ATOMIC_INIT(0);



notrace void arch_touch_nmi_watchdog(void)

#ifndef CONFIG_PPC

notrace void __weak arch_touch_nmi_watchdog(void)

{

	/*

	 * Using __raw here because some code paths have
@@ -41,6 +38,7 @@ notrace void arch_touch_nmi_watchdog(void) 
	raw_cpu_write(watchdog_nmi_touch, true);

}

EXPORT_SYMBOL(arch_touch_nmi_watchdog);

#endif



#ifdef CONFIG_HARDLOCKUP_CHECK_TIMESTAMP

static DEFINE_PER_CPU(ktime_t, last_timestamp);
@@ -98,22 +96,8 @@ static inline bool watchdog_check_timestamp(void) 
}

#endif



static struct perf_event_attr wd_hw_attr = {

	.type		= PERF_TYPE_HARDWARE,

	.config		= PERF_COUNT_HW_CPU_CYCLES,

	.size		= sizeof(struct perf_event_attr),

	.pinned		= 1,

	.disabled	= 1,

};



/* Callback function for perf event subsystem */

static void watchdog_overflow_callback(struct perf_event *event,

				       struct perf_sample_data *data,

				       struct pt_regs *regs)

void watchdog_hardlockup_check(struct pt_regs *regs)

{

	/* Ensure the watchdog never gets throttled */

	event->hw.interrupts = 0;



	if (__this_cpu_read(watchdog_nmi_touch) == true) {

		__this_cpu_write(watchdog_nmi_touch, false);

		return;
@@ -163,6 +147,31 @@ static void watchdog_overflow_callback(struct perf_event *event, 
	return;

}



#ifdef CONFIG_HARDLOCKUP_DETECTOR_PERF

static DEFINE_PER_CPU(struct perf_event *, watchdog_ev);

static DEFINE_PER_CPU(struct perf_event *, dead_event);

static struct cpumask dead_events_mask;

static atomic_t watchdog_cpus = ATOMIC_INIT(0);



static struct perf_event_attr wd_hw_attr = {

	.type		= PERF_TYPE_HARDWARE,

	.config		= PERF_COUNT_HW_CPU_CYCLES,

	.size		= sizeof(struct perf_event_attr),

	.pinned		= 1,

	.disabled	= 1,

};



/* Callback function for perf event subsystem */

static void watchdog_overflow_callback(struct perf_event *event,

				       struct perf_sample_data *data,

				       struct pt_regs *regs)

{

	/* Ensure the watchdog never gets throttled */

	event->hw.interrupts = 0;



	watchdog_hardlockup_check(regs);

}



static int hardlockup_detector_event_create(void)

{

	unsigned int cpu = smp_processor_id();
@@ -294,3 +303,4 @@ int __init hardlockup_detector_perf_init(void) 
	}

	return ret;

}

#endif /* CONFIG_HARDLOCKUP_DETECTOR_PERF */

lib/Kconfig.debug

+1 −1
Original line number Diff line number Diff line
@@ -979,7 +979,7 @@ config HARDLOCKUP_DETECTOR 
	bool "Detect Hard Lockups"

	depends on DEBUG_KERNEL && !S390

	depends on HAVE_HARDLOCKUP_DETECTOR_PERF || HAVE_HARDLOCKUP_DETECTOR_ARCH

	select LOCKUP_DETECTOR

	select SOFTLOCKUP_DETECTOR

	select HARDLOCKUP_DETECTOR_PERF if HAVE_HARDLOCKUP_DETECTOR_PERF

	select HARDLOCKUP_DETECTOR_ARCH if HAVE_HARDLOCKUP_DETECTOR_ARCH

	help