diff options
| -rw-r--r-- | Documentation/filesystems/proc.txt | 14 | ||||
| -rw-r--r-- | arch/i386/kernel/nmi.c | 21 | ||||
| -rw-r--r-- | arch/x86_64/kernel/nmi.c | 21 |
3 files changed, 17 insertions, 39 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt index 99902ae6804e..7db71d6fba82 100644 --- a/Documentation/filesystems/proc.txt +++ b/Documentation/filesystems/proc.txt @@ -1124,11 +1124,15 @@ debugging information is displayed on console. NMI switch that most IA32 servers have fires unknown NMI up, for example. If a system hangs up, try pressing the NMI switch. -[NOTE] - This function and oprofile share a NMI callback. Therefore this function - cannot be enabled when oprofile is activated. - And NMI watchdog will be disabled when the value in this file is set to - non-zero. +nmi_watchdog +------------ + +Enables/Disables the NMI watchdog on x86 systems. When the value is non-zero +the NMI watchdog is enabled and will continuously test all online cpus to +determine whether or not they are still functioning properly. + +Because the NMI watchdog shares registers with oprofile, by disabling the NMI +watchdog, oprofile may have more registers to utilize. 2.4 /proc/sys/vm - The virtual memory subsystem diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index 28065d0b71a9..6241e4448cab 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -847,7 +847,7 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu) } /* - * proc handler for /proc/sys/kernel/nmi_watchdog + * 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) @@ -861,8 +861,8 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, return 0; if (atomic_read(&nmi_active) < 0) { - printk(KERN_WARNING "NMI watchdog is permanently disabled\n"); - return -EINVAL; + printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); + return -EIO; } if (nmi_watchdog == NMI_DEFAULT) { @@ -872,24 +872,11 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, nmi_watchdog = NMI_IO_APIC; } - if (nmi_watchdog == NMI_LOCAL_APIC) - { + if (nmi_watchdog == NMI_LOCAL_APIC) { if (nmi_watchdog_enabled) enable_lapic_nmi_watchdog(); else disable_lapic_nmi_watchdog(); - } else if (nmi_watchdog == NMI_IO_APIC) { - /* FIXME - * for some reason these functions don't work - */ - printk("Can not enable/disable NMI on IO APIC\n"); - return -EINVAL; -#if 0 - if (nmi_watchdog_enabled) - enable_timer_nmi_watchdog(); - else - disable_timer_nmi_watchdog(); -#endif } else { printk( KERN_WARNING "NMI watchdog doesn't know what hardware to touch\n"); diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index 3a17411a9a19..dd57410dad51 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -167,7 +167,7 @@ static __cpuinit inline int nmi_known_cpu(void) } /* Run after command line and cpu_init init, but before all other checks */ -void __cpuinit nmi_watchdog_default(void) +void nmi_watchdog_default(void) { if (nmi_watchdog != NMI_DEFAULT) return; @@ -766,32 +766,19 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, if (atomic_read(&nmi_active) < 0) { printk( KERN_WARNING "NMI watchdog is permanently disabled\n"); - return -EINVAL; + return -EIO; } /* if nmi_watchdog is not set yet, then set it */ nmi_watchdog_default(); - if (nmi_watchdog == NMI_LOCAL_APIC) - { + if (nmi_watchdog == NMI_LOCAL_APIC) { if (nmi_watchdog_enabled) enable_lapic_nmi_watchdog(); else disable_lapic_nmi_watchdog(); - } else if (nmi_watchdog == NMI_IO_APIC) { - /* FIXME - * for some reason these functions don't work - */ - printk("Can not enable/disable NMI on IO APIC\n"); - return -EIO; -#if 0 - if (nmi_watchdog_enabled) - enable_timer_nmi_watchdog(); - else - disable_timer_nmi_watchdog(); -#endif } else { - printk(KERN_WARNING + printk( KERN_WARNING "NMI watchdog doesn't know what hardware to touch\n"); return -EIO; } |