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Commit 1798bc22 authored by Cyrill Gorcunov's avatar Cyrill Gorcunov Committed by Thomas Gleixner
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x86: nmi_32/64.c - merge down nmi_32.c and nmi_64.c to nmi.c 


Signed-off-by: default avatarCyrill Gorcunov <gorcunov@gmail.com>
Cc: hpa@zytor.com
Cc: mingo@redhat.com
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent fd5cea02
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arch/x86/kernel/Makefile
+ 1
− 1
View file @ 1798bc22
...@@ -53,7 +53,7 @@ obj-$(CONFIG_X86_32_SMP) += smpcommon.o ...@@ -53,7 +53,7 @@ obj-$(CONFIG_X86_32_SMP) += smpcommon.o
obj-$(CONFIG_X86_64_SMP) += tsc_sync.o smpcommon.o obj-$(CONFIG_X86_64_SMP) += tsc_sync.o smpcommon.o
obj-$(CONFIG_X86_TRAMPOLINE) += trampoline_$(BITS).o obj-$(CONFIG_X86_TRAMPOLINE) += trampoline_$(BITS).o
obj-$(CONFIG_X86_MPPARSE) += mpparse.o obj-$(CONFIG_X86_MPPARSE) += mpparse.o
obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi_$(BITS).o obj-$(CONFIG_X86_LOCAL_APIC) += apic_$(BITS).o nmi.o
obj-$(CONFIG_X86_IO_APIC) += io_apic_$(BITS).o obj-$(CONFIG_X86_IO_APIC) += io_apic_$(BITS).o
obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o obj-$(CONFIG_X86_REBOOTFIXUPS) += reboot_fixups_32.o
obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o obj-$(CONFIG_KEXEC) += machine_kexec_$(BITS).o
......
arch/x86/kernel/nmi_32.c → arch/x86/kernel/nmi.c
+ 64
− 37
View file @ 1798bc22
...@@ -11,10 +11,11 @@ ...@@ -11,10 +11,11 @@
* Mikael Pettersson : PM converted to driver model. Disable/enable API. * Mikael Pettersson : PM converted to driver model. Disable/enable API.
*/ */
#include <linux/nmi.h>
#include <linux/mm.h>
#include <linux/delay.h> #include <linux/delay.h>
#include <linux/interrupt.h> #include <linux/interrupt.h>
#include <linux/module.h> #include <linux/module.h>
#include <linux/nmi.h>
#include <linux/sysdev.h> #include <linux/sysdev.h>
#include <linux/sysctl.h> #include <linux/sysctl.h>
#include <linux/percpu.h> #include <linux/percpu.h>
...@@ -22,13 +23,15 @@ ...@@ -22,13 +23,15 @@
#include <linux/cpumask.h> #include <linux/cpumask.h>
#include <linux/kernel_stat.h> #include <linux/kernel_stat.h>
#include <linux/kdebug.h> #include <linux/kdebug.h>
#include <linux/slab.h>
#include <asm/smp.h> #include <asm/smp.h>
#include <asm/nmi.h> #include <asm/nmi.h>
#include <asm/proto.h>
#include <asm/timer.h> #include <asm/timer.h>
#include "mach_traps.h" #include <asm/mce.h>
#include <mach_traps.h>
int unknown_nmi_panic; int unknown_nmi_panic;
int nmi_watchdog_enabled; int nmi_watchdog_enabled;
...@@ -45,19 +48,25 @@ atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */ ...@@ -45,19 +48,25 @@ atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */
static int panic_on_timeout; static int panic_on_timeout;
unsigned int nmi_watchdog = NMI_DEFAULT; unsigned int nmi_watchdog = NMI_DEFAULT;
static unsigned int nmi_hz = HZ;
static unsigned int nmi_hz = HZ;
static DEFINE_PER_CPU(short, wd_enabled); static DEFINE_PER_CPU(short, wd_enabled);
static int endflag __initdata = 0; static int endflag __initdata = 0;
static inline unsigned int get_nmi_count(int cpu) static inline unsigned int get_nmi_count(int cpu)
{ {
#ifdef CONFIG_X86_64
return cpu_pda(cpu)->__nmi_count;
#else
return nmi_count(cpu); return nmi_count(cpu);
#endif
} }
static inline int mce_in_progress(void) static inline int mce_in_progress(void)
{ {
#if defined(CONFIX_X86_64) && defined(CONFIG_X86_MCE)
return atomic_read(&mce_entry) > 0;
#endif
return 0; return 0;
} }
...@@ -67,8 +76,12 @@ static inline int mce_in_progress(void) ...@@ -67,8 +76,12 @@ static inline int mce_in_progress(void)
*/ */
static inline unsigned int get_timer_irqs(int cpu) static inline unsigned int get_timer_irqs(int cpu)
{ {
#ifdef CONFIG_X86_64
return read_pda(apic_timer_irqs) + read_pda(irq0_irqs);
#else
return per_cpu(irq_stat, cpu).apic_timer_irqs + return per_cpu(irq_stat, cpu).apic_timer_irqs +
per_cpu(irq_stat, cpu).irq0_irqs; per_cpu(irq_stat, cpu).irq0_irqs;
#endif
} }
/* Run after command line and cpu_init init, but before all other checks */ /* Run after command line and cpu_init init, but before all other checks */
...@@ -76,26 +89,33 @@ void nmi_watchdog_default(void) ...@@ -76,26 +89,33 @@ void nmi_watchdog_default(void)
{ {
if (nmi_watchdog != NMI_DEFAULT) if (nmi_watchdog != NMI_DEFAULT)
return; return;
#ifdef CONFIG_X86_64
nmi_watchdog = NMI_NONE;
#else
if (lapic_watchdog_ok()) if (lapic_watchdog_ok())
nmi_watchdog = NMI_LOCAL_APIC; nmi_watchdog = NMI_LOCAL_APIC;
else else
nmi_watchdog = NMI_IO_APIC; nmi_watchdog = NMI_IO_APIC;
#endif
} }
#ifdef CONFIG_SMP #ifdef CONFIG_SMP
/* The performance counters used by NMI_LOCAL_APIC don't trigger when /*
* The performance counters used by NMI_LOCAL_APIC don't trigger when
* the CPU is idle. To make sure the NMI watchdog really ticks on all * the CPU is idle. To make sure the NMI watchdog really ticks on all
* CPUs during the test make them busy. * CPUs during the test make them busy.
*/ */
static __init void nmi_cpu_busy(void *data) static __init void nmi_cpu_busy(void *data)
{ {
local_irq_enable_in_hardirq(); local_irq_enable_in_hardirq();
/* Intentionally don't use cpu_relax here. This is /*
to make sure that the performance counter really ticks, * Intentionally don't use cpu_relax here. This is
even if there is a simulator or similar that catches the * to make sure that the performance counter really ticks,
pause instruction. On a real HT machine this is fine because * even if there is a simulator or similar that catches the
all other CPUs are busy with "useless" delay loops and don't * pause instruction. On a real HT machine this is fine because
care if they get somewhat less cycles. */ * all other CPUs are busy with "useless" delay loops and don't
* care if they get somewhat less cycles.
*/
while (endflag == 0) while (endflag == 0)
mb(); mb();
} }
...@@ -106,7 +126,7 @@ int __init check_nmi_watchdog(void) ...@@ -106,7 +126,7 @@ int __init check_nmi_watchdog(void)
unsigned int *prev_nmi_count; unsigned int *prev_nmi_count;
int cpu; int cpu;
if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED)) if (nmi_watchdog == NMI_NONE || nmi_watchdog == NMI_DISABLED)
return 0; return 0;
if (!atomic_read(&nmi_active)) if (!atomic_read(&nmi_active))
...@@ -126,7 +146,7 @@ int __init check_nmi_watchdog(void) ...@@ -126,7 +146,7 @@ int __init check_nmi_watchdog(void)
for_each_possible_cpu(cpu) for_each_possible_cpu(cpu)
prev_nmi_count[cpu] = get_nmi_count(cpu); prev_nmi_count[cpu] = get_nmi_count(cpu);
local_irq_enable(); local_irq_enable();
mdelay((20*1000)/nmi_hz); // wait 20 ticks mdelay((20 * 1000) / nmi_hz); /* wait 20 ticks */
for_each_online_cpu(cpu) { for_each_online_cpu(cpu) {
if (!per_cpu(wd_enabled, cpu)) if (!per_cpu(wd_enabled, cpu))
...@@ -149,16 +169,20 @@ int __init check_nmi_watchdog(void) ...@@ -149,16 +169,20 @@ int __init check_nmi_watchdog(void)
} }
printk("OK.\n"); printk("OK.\n");
/* now that we know it works we can reduce NMI frequency to /*
something more reasonable; makes a difference in some configs */ * now that we know it works we can reduce NMI frequency to
* something more reasonable; makes a difference in some configs
*/
if (nmi_watchdog == NMI_LOCAL_APIC) if (nmi_watchdog == NMI_LOCAL_APIC)
nmi_hz = lapic_adjust_nmi_hz(1); nmi_hz = lapic_adjust_nmi_hz(1);
kfree(prev_nmi_count); kfree(prev_nmi_count);
return 0; return 0;
error: error:
#ifdef CONFIG_X86_32
timer_ack = !cpu_has_tsc; timer_ack = !cpu_has_tsc;
#endif
return -1; return -1;
} }
...@@ -176,18 +200,17 @@ static int __init setup_nmi_watchdog(char *str) ...@@ -176,18 +200,17 @@ static int __init setup_nmi_watchdog(char *str)
get_option(&str, &nmi); get_option(&str, &nmi);
if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE)) if (nmi >= NMI_INVALID || nmi < NMI_NONE)
return 0; return 0;
nmi_watchdog = nmi; nmi_watchdog = nmi;
return 1; return 1;
} }
__setup("nmi_watchdog=", setup_nmi_watchdog); __setup("nmi_watchdog=", setup_nmi_watchdog);
/*
/* Suspend/resume support */ * Suspend/resume support
*/
#ifdef CONFIG_PM #ifdef CONFIG_PM
static int nmi_pm_active; /* nmi_active before suspend */ static int nmi_pm_active; /* nmi_active before suspend */
...@@ -211,7 +234,6 @@ static int lapic_nmi_resume(struct sys_device *dev) ...@@ -211,7 +234,6 @@ static int lapic_nmi_resume(struct sys_device *dev)
return 0; return 0;
} }
static struct sysdev_class nmi_sysclass = { static struct sysdev_class nmi_sysclass = {
.name = "lapic_nmi", .name = "lapic_nmi",
.resume = lapic_nmi_resume, .resume = lapic_nmi_resume,
...@@ -227,7 +249,8 @@ static int __init init_lapic_nmi_sysfs(void) ...@@ -227,7 +249,8 @@ static int __init init_lapic_nmi_sysfs(void)
{ {
int error; int error;
/* should really be a BUG_ON but b/c this is an /*
* should really be a BUG_ON but b/c this is an
* init call, it just doesn't work. -dcz * init call, it just doesn't work. -dcz
*/ */
if (nmi_watchdog != NMI_LOCAL_APIC) if (nmi_watchdog != NMI_LOCAL_APIC)
...@@ -241,6 +264,7 @@ static int __init init_lapic_nmi_sysfs(void) ...@@ -241,6 +264,7 @@ static int __init init_lapic_nmi_sysfs(void)
error = sysdev_register(&device_lapic_nmi); error = sysdev_register(&device_lapic_nmi);
return error; return error;
} }
/* must come after the local APIC's device_initcall() */ /* must come after the local APIC's device_initcall() */
late_initcall(init_lapic_nmi_sysfs); late_initcall(init_lapic_nmi_sysfs);
...@@ -281,12 +305,13 @@ void setup_apic_nmi_watchdog(void *unused) ...@@ -281,12 +305,13 @@ void setup_apic_nmi_watchdog(void *unused)
/* cheap hack to support suspend/resume */ /* cheap hack to support suspend/resume */
/* if cpu0 is not active neither should the other cpus */ /* if cpu0 is not active neither should the other cpus */
if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0)) if (smp_processor_id() != 0 && atomic_read(&nmi_active) <= 0)
return; return;
switch (nmi_watchdog) { switch (nmi_watchdog) {
case NMI_LOCAL_APIC: case NMI_LOCAL_APIC:
__get_cpu_var(wd_enabled) = 1; /* enable it before to avoid race with handler */ /* enable it before to avoid race with handler */
__get_cpu_var(wd_enabled) = 1;
if (lapic_watchdog_init(nmi_hz) < 0) { if (lapic_watchdog_init(nmi_hz) < 0) {
__get_cpu_var(wd_enabled) = 0; __get_cpu_var(wd_enabled) = 0;
return; return;
...@@ -301,9 +326,9 @@ void setup_apic_nmi_watchdog(void *unused) ...@@ -301,9 +326,9 @@ void setup_apic_nmi_watchdog(void *unused)
void stop_apic_nmi_watchdog(void *unused) void stop_apic_nmi_watchdog(void *unused)
{ {
/* only support LOCAL and IO APICs for now */ /* only support LOCAL and IO APICs for now */
if ((nmi_watchdog != NMI_LOCAL_APIC) && if (nmi_watchdog != NMI_LOCAL_APIC &&
(nmi_watchdog != NMI_IO_APIC)) nmi_watchdog != NMI_IO_APIC)
return; return;
if (__get_cpu_var(wd_enabled) == 0) if (__get_cpu_var(wd_enabled) == 0)
return; return;
if (nmi_watchdog == NMI_LOCAL_APIC) if (nmi_watchdog == NMI_LOCAL_APIC)
...@@ -323,8 +348,7 @@ void stop_apic_nmi_watchdog(void *unused) ...@@ -323,8 +348,7 @@ void stop_apic_nmi_watchdog(void *unused)
* since NMIs don't listen to _any_ locks, we have to be extremely * since NMIs don't listen to _any_ locks, we have to be extremely
* careful not to rely on unsafe variables. The printk might lock * careful not to rely on unsafe variables. The printk might lock
* up though, so we have to break up any console locks first ... * up though, so we have to break up any console locks first ...
* [when there will be more tty-related locks, break them up * [when there will be more tty-related locks, break them up here too!]
* here too!]
*/ */
static DEFINE_PER_CPU(unsigned, last_irq_sum); static DEFINE_PER_CPU(unsigned, last_irq_sum);
...@@ -357,7 +381,6 @@ EXPORT_SYMBOL(touch_nmi_watchdog); ...@@ -357,7 +381,6 @@ EXPORT_SYMBOL(touch_nmi_watchdog);
notrace __kprobes int notrace __kprobes int
nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
{ {
/* /*
* Since current_thread_info()-> is always on the stack, and we * Since current_thread_info()-> is always on the stack, and we
* always switch the stack NMI-atomically, it's safe to use * always switch the stack NMI-atomically, it's safe to use
...@@ -403,7 +426,7 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) ...@@ -403,7 +426,7 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
* wait a few IRQs (5 seconds) before doing the oops ... * wait a few IRQs (5 seconds) before doing the oops ...
*/ */
local_inc(&__get_cpu_var(alert_counter)); local_inc(&__get_cpu_var(alert_counter));
if (local_read(&__get_cpu_var(alert_counter)) == 5*nmi_hz) if (local_read(&__get_cpu_var(alert_counter)) == 5 * nmi_hz)
/* /*
* die_nmi will return ONLY if NOTIFY_STOP happens.. * die_nmi will return ONLY if NOTIFY_STOP happens..
*/ */
...@@ -413,6 +436,7 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) ...@@ -413,6 +436,7 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
__get_cpu_var(last_irq_sum) = sum; __get_cpu_var(last_irq_sum) = sum;
local_set(&__get_cpu_var(alert_counter), 0); local_set(&__get_cpu_var(alert_counter), 0);
} }
/* see if the nmi watchdog went off */ /* see if the nmi watchdog went off */
if (!__get_cpu_var(wd_enabled)) if (!__get_cpu_var(wd_enabled))
return rc; return rc;
...@@ -421,7 +445,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason) ...@@ -421,7 +445,8 @@ nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
rc |= lapic_wd_event(nmi_hz); rc |= lapic_wd_event(nmi_hz);
break; break;
case NMI_IO_APIC: case NMI_IO_APIC:
/* don't know how to accurately check for this. /*
* don't know how to accurately check for this.
* just assume it was a watchdog timer interrupt * just assume it was a watchdog timer interrupt
* This matches the old behaviour. * This matches the old behaviour.
*/ */
...@@ -458,7 +483,8 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, ...@@ -458,7 +483,8 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
return 0; return 0;
if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) { if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) {
printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); printk(KERN_WARNING
"NMI watchdog is permanently disabled\n");
return -EIO; return -EIO;
} }
...@@ -471,14 +497,14 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, ...@@ -471,14 +497,14 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
else else
disable_lapic_nmi_watchdog(); disable_lapic_nmi_watchdog();
} else { } else {
printk( KERN_WARNING printk(KERN_WARNING
"NMI watchdog doesn't know what hardware to touch\n"); "NMI watchdog doesn't know what hardware to touch\n");
return -EIO; return -EIO;
} }
return 0; return 0;
} }
#endif #endif /* CONFIG_SYSCTL */
int do_nmi_callback(struct pt_regs *regs, int cpu) int do_nmi_callback(struct pt_regs *regs, int cpu)
{ {
...@@ -504,3 +530,4 @@ void __trigger_all_cpu_backtrace(void) ...@@ -504,3 +530,4 @@ void __trigger_all_cpu_backtrace(void)
EXPORT_SYMBOL(nmi_active); EXPORT_SYMBOL(nmi_active);
EXPORT_SYMBOL(nmi_watchdog); EXPORT_SYMBOL(nmi_watchdog);
arch/x86/kernel/nmi_64.c deleted 100644 → 0
+ 0
− 477
View file @ fd5cea02
/*
* NMI watchdog support on APIC systems
*
* Started by Ingo Molnar <mingo@redhat.com>
*
* Fixes:
* Mikael Pettersson : AMD K7 support for local APIC NMI watchdog.
* Mikael Pettersson : Power Management for local APIC NMI watchdog.
* Pavel Machek and
* Mikael Pettersson : PM converted to driver model. Disable/enable API.
*/
#include <linux/nmi.h>
#include <linux/mm.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/sysdev.h>
#include <linux/sysctl.h>
#include <linux/kprobes.h>
#include <linux/cpumask.h>
#include <linux/kdebug.h>
#include <asm/smp.h>
#include <asm/nmi.h>
#include <asm/proto.h>
#include <asm/mce.h>
#include <mach_traps.h>
int unknown_nmi_panic;
int nmi_watchdog_enabled;
static cpumask_t backtrace_mask = CPU_MASK_NONE;
/* nmi_active:
* >0: the lapic NMI watchdog is active, but can be disabled
* <0: the lapic NMI watchdog has not been set up, and cannot
* be enabled
* 0: the lapic NMI watchdog is disabled, but can be enabled
*/
atomic_t nmi_active = ATOMIC_INIT(0); /* oprofile uses this */
static int panic_on_timeout;
unsigned int nmi_watchdog = NMI_DEFAULT;
static unsigned int nmi_hz = HZ;
static DEFINE_PER_CPU(short, wd_enabled);
static int endflag __initdata = 0;
static inline unsigned int get_nmi_count(int cpu)
{
return cpu_pda(cpu)->__nmi_count;
}
static inline int mce_in_progress(void)
{
#ifdef CONFIG_X86_MCE
return atomic_read(&mce_entry) > 0;
#endif
return 0;
}
/*
* Take the local apic timer and PIT/HPET into account. We don't
* know which one is active, when we have highres/dyntick on
*/
static inline unsigned int get_timer_irqs(int cpu)
{
return read_pda(apic_timer_irqs) + read_pda(irq0_irqs);
}
/* Run after command line and cpu_init init, but before all other checks */
void nmi_watchdog_default(void)
{
if (nmi_watchdog != NMI_DEFAULT)
return;
nmi_watchdog = NMI_NONE;
}
#ifdef CONFIG_SMP
/* The performance counters used by NMI_LOCAL_APIC don't trigger when
* the CPU is idle. To make sure the NMI watchdog really ticks on all
* CPUs during the test make them busy.
*/
static __init void nmi_cpu_busy(void *data)
{
local_irq_enable_in_hardirq();
/* Intentionally don't use cpu_relax here. This is
to make sure that the performance counter really ticks,
even if there is a simulator or similar that catches the
pause instruction. On a real HT machine this is fine because
all other CPUs are busy with "useless" delay loops and don't
care if they get somewhat less cycles. */
while (endflag == 0)
mb();
}
#endif
int __init check_nmi_watchdog(void)
{
unsigned int *prev_nmi_count;
int cpu;
if ((nmi_watchdog == NMI_NONE) || (nmi_watchdog == NMI_DISABLED))
return 0;
if (!atomic_read(&nmi_active))
return 0;
prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL);
if (!prev_nmi_count)
return -1;
printk(KERN_INFO "Testing NMI watchdog ... ");
#ifdef CONFIG_SMP
if (nmi_watchdog == NMI_LOCAL_APIC)
smp_call_function(nmi_cpu_busy, (void *)&endflag, 0, 0);
#endif
for_each_possible_cpu(cpu)
prev_nmi_count[cpu] = get_nmi_count(cpu);
local_irq_enable();
mdelay((20*1000)/nmi_hz); // wait 20 ticks
for_each_online_cpu(cpu) {
if (!per_cpu(wd_enabled, cpu))
continue;
if (get_nmi_count(cpu) - prev_nmi_count[cpu] <= 5) {
printk(KERN_WARNING "WARNING: CPU#%d: NMI "
"appears to be stuck (%d->%d)!\n",
cpu,
prev_nmi_count[cpu],
get_nmi_count(cpu));
per_cpu(wd_enabled, cpu) = 0;
atomic_dec(&nmi_active);
}
}
endflag = 1;
if (!atomic_read(&nmi_active)) {
kfree(prev_nmi_count);
atomic_set(&nmi_active, -1);
return -1;
}
printk("OK.\n");
/* now that we know it works we can reduce NMI frequency to
something more reasonable; makes a difference in some configs */
if (nmi_watchdog == NMI_LOCAL_APIC)
nmi_hz = lapic_adjust_nmi_hz(1);
kfree(prev_nmi_count);
return 0;
}
static int __init setup_nmi_watchdog(char *str)
{
int nmi;
if (!strncmp(str,"panic",5)) {
panic_on_timeout = 1;
str = strchr(str, ',');
if (!str)
return 1;
++str;
}
get_option(&str, &nmi);
if ((nmi >= NMI_INVALID) || (nmi < NMI_NONE))
return 0;
nmi_watchdog = nmi;
return 1;
}
__setup("nmi_watchdog=", setup_nmi_watchdog);
#ifdef CONFIG_PM
static int nmi_pm_active; /* nmi_active before suspend */
static int lapic_nmi_suspend(struct sys_device *dev, pm_message_t state)
{
/* only CPU0 goes here, other CPUs should be offline */
nmi_pm_active = atomic_read(&nmi_active);
stop_apic_nmi_watchdog(NULL);
BUG_ON(atomic_read(&nmi_active) != 0);
return 0;
}
static int lapic_nmi_resume(struct sys_device *dev)
{
/* only CPU0 goes here, other CPUs should be offline */
if (nmi_pm_active > 0) {
setup_apic_nmi_watchdog(NULL);
touch_nmi_watchdog();
}
return 0;
}
static struct sysdev_class nmi_sysclass = {
.name = "lapic_nmi",
.resume = lapic_nmi_resume,
.suspend = lapic_nmi_suspend,
};
static struct sys_device device_lapic_nmi = {
.id = 0,
.cls = &nmi_sysclass,
};
static int __init init_lapic_nmi_sysfs(void)
{
int error;
/* should really be a BUG_ON but b/c this is an
* init call, it just doesn't work. -dcz
*/
if (nmi_watchdog != NMI_LOCAL_APIC)
return 0;
if (atomic_read(&nmi_active) < 0)
return 0;
error = sysdev_class_register(&nmi_sysclass);
if (!error)
error = sysdev_register(&device_lapic_nmi);
return error;
}
/* must come after the local APIC's device_initcall() */
late_initcall(init_lapic_nmi_sysfs);
#endif /* CONFIG_PM */
static void __acpi_nmi_enable(void *__unused)
{
apic_write_around(APIC_LVT0, APIC_DM_NMI);
}
/*
* Enable timer based NMIs on all CPUs:
*/
void acpi_nmi_enable(void)
{
if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
on_each_cpu(__acpi_nmi_enable, NULL, 0, 1);
}
static void __acpi_nmi_disable(void *__unused)
{
apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED);
}
/*
* Disable timer based NMIs on all CPUs:
*/
void acpi_nmi_disable(void)
{
if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
on_each_cpu(__acpi_nmi_disable, NULL, 0, 1);
}
void setup_apic_nmi_watchdog(void *unused)
{
if (__get_cpu_var(wd_enabled))
return;
/* cheap hack to support suspend/resume */
/* if cpu0 is not active neither should the other cpus */
if ((smp_processor_id() != 0) && (atomic_read(&nmi_active) <= 0))
return;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
__get_cpu_var(wd_enabled) = 1;
if (lapic_watchdog_init(nmi_hz) < 0) {
__get_cpu_var(wd_enabled) = 0;
return;
}
/* FALL THROUGH */
case NMI_IO_APIC:
__get_cpu_var(wd_enabled) = 1;
atomic_inc(&nmi_active);
}
}
void stop_apic_nmi_watchdog(void *unused)
{
/* only support LOCAL and IO APICs for now */
if ((nmi_watchdog != NMI_LOCAL_APIC) &&
(nmi_watchdog != NMI_IO_APIC))
return;
if (__get_cpu_var(wd_enabled) == 0)
return;
if (nmi_watchdog == NMI_LOCAL_APIC)
lapic_watchdog_stop();
__get_cpu_var(wd_enabled) = 0;
atomic_dec(&nmi_active);
}
/*
* the best way to detect whether a CPU has a 'hard lockup' problem
* is to check it's local APIC timer IRQ counts. If they are not
* changing then that CPU has some problem.
*
* as these watchdog NMI IRQs are generated on every CPU, we only
* have to check the current processor.
*/
static DEFINE_PER_CPU(unsigned, last_irq_sum);
static DEFINE_PER_CPU(local_t, alert_counter);
static DEFINE_PER_CPU(int, nmi_touch);
void touch_nmi_watchdog(void)
{
if (nmi_watchdog > 0) {
unsigned cpu;
/*
* Tell other CPUs to reset their alert counters. We cannot
* do it ourselves because the alert count increase is not
* atomic.
*/
for_each_present_cpu(cpu) {
if (per_cpu(nmi_touch, cpu) != 1)
per_cpu(nmi_touch, cpu) = 1;
}
}
touch_softlockup_watchdog();
}
EXPORT_SYMBOL(touch_nmi_watchdog);
notrace __kprobes int
nmi_watchdog_tick(struct pt_regs *regs, unsigned reason)
{
unsigned int sum;
int touched = 0;
int cpu = smp_processor_id();
int rc = 0;
/* check for other users first */
if (notify_die(DIE_NMI, "nmi", regs, reason, 2, SIGINT)
== NOTIFY_STOP) {
rc = 1;
touched = 1;
}
sum = get_timer_irqs(cpu);
if (__get_cpu_var(nmi_touch)) {
__get_cpu_var(nmi_touch) = 0;
touched = 1;
}
if (cpu_isset(cpu, backtrace_mask)) {
static DEFINE_SPINLOCK(lock); /* Serialise the printks */
spin_lock(&lock);
printk("NMI backtrace for cpu %d\n", cpu);
dump_stack();
spin_unlock(&lock);
cpu_clear(cpu, backtrace_mask);
}
if (mce_in_progress())
touched = 1;
/* if the apic timer isn't firing, this cpu isn't doing much */
if (!touched && __get_cpu_var(last_irq_sum) == sum) {
/*
* Ayiee, looks like this CPU is stuck ...
* wait a few IRQs (5 seconds) before doing the oops ...
*/
local_inc(&__get_cpu_var(alert_counter));
if (local_read(&__get_cpu_var(alert_counter)) == 5*nmi_hz)
die_nmi("NMI Watchdog detected LOCKUP",
regs, panic_on_timeout);
} else {
__get_cpu_var(last_irq_sum) = sum;
local_set(&__get_cpu_var(alert_counter), 0);
}
/* see if the nmi watchdog went off */
if (!__get_cpu_var(wd_enabled))
return rc;
switch (nmi_watchdog) {
case NMI_LOCAL_APIC:
rc |= lapic_wd_event(nmi_hz);
break;
case NMI_IO_APIC:
/* don't know how to accurately check for this.
* just assume it was a watchdog timer interrupt
* This matches the old behaviour.
*/
rc = 1;
break;
}
return rc;
}
#ifdef CONFIG_SYSCTL
static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu)
{
unsigned char reason = get_nmi_reason();
char buf[64];
sprintf(buf, "NMI received for unknown reason %02x\n", reason);
die_nmi(buf, regs, 1); /* Always panic here */
return 0;
}
/*
* proc handler for /proc/sys/kernel/nmi
*/
int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
void __user *buffer, size_t *length, loff_t *ppos)
{
int old_state;
nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0;
old_state = nmi_watchdog_enabled;
proc_dointvec(table, write, file, buffer, length, ppos);
if (!!old_state == !!nmi_watchdog_enabled)
return 0;
if (atomic_read(&nmi_active) < 0 || nmi_watchdog == NMI_DISABLED) {
printk( KERN_WARNING "NMI watchdog is permanently disabled\n");
return -EIO;
}
/* if nmi_watchdog is not set yet, then set it */
nmi_watchdog_default();
if (nmi_watchdog == NMI_LOCAL_APIC) {
if (nmi_watchdog_enabled)
enable_lapic_nmi_watchdog();
else
disable_lapic_nmi_watchdog();
} else {
printk( KERN_WARNING
"NMI watchdog doesn't know what hardware to touch\n");
return -EIO;
}
return 0;
}
#endif
int do_nmi_callback(struct pt_regs *regs, int cpu)
{
#ifdef CONFIG_SYSCTL
if (unknown_nmi_panic)
return unknown_nmi_panic_callback(regs, cpu);
#endif
return 0;
}
void __trigger_all_cpu_backtrace(void)
{
int i;
backtrace_mask = cpu_online_map;
/* Wait for up to 10 seconds for all CPUs to do the backtrace */
for (i = 0; i < 10 * 1000; i++) {
if (cpus_empty(backtrace_mask))
break;
mdelay(1);
}
}
EXPORT_SYMBOL(nmi_active);
EXPORT_SYMBOL(nmi_watchdog);
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