diff options
| -rw-r--r-- | arch/i386/kernel/nmi.c | 26 | ||||
| -rw-r--r-- | arch/x86_64/kernel/nmi.c | 29 | ||||
| -rw-r--r-- | include/asm-i386/nmi.h | 8 | ||||
| -rw-r--r-- | include/asm-x86_64/nmi.h | 3 | ||||
| -rw-r--r-- | include/linux/nmi.h | 5 | ||||
| -rw-r--r-- | lib/spinlock_debug.c | 4 |
6 files changed, 74 insertions, 1 deletions
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c index eaafe233a5da..171194ccb7bc 100644 --- a/arch/i386/kernel/nmi.c +++ b/arch/i386/kernel/nmi.c @@ -22,6 +22,7 @@ #include <linux/percpu.h> #include <linux/dmi.h> #include <linux/kprobes.h> +#include <linux/cpumask.h> #include <asm/smp.h> #include <asm/nmi.h> @@ -42,6 +43,8 @@ int nmi_watchdog_enabled; static DEFINE_PER_CPU(unsigned long, perfctr_nmi_owner); static DEFINE_PER_CPU(unsigned long, evntsel_nmi_owner[3]); +static cpumask_t backtrace_mask = CPU_MASK_NONE; + /* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's * offset from MSR_P4_BSU_ESCR0. It will be the max for all platforms (for now) */ @@ -907,6 +910,16 @@ __kprobes int nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) 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); + } + sum = per_cpu(irq_stat, cpu).apic_timer_irqs; /* if the apic timer isn't firing, this cpu isn't doing much */ @@ -1033,6 +1046,19 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, #endif +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); EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi); diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c index 7af9cb3e2d99..27e95e7922c1 100644 --- a/arch/x86_64/kernel/nmi.c +++ b/arch/x86_64/kernel/nmi.c @@ -12,14 +12,15 @@ * 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/nmi.h> #include <linux/sysctl.h> #include <linux/kprobes.h> +#include <linux/cpumask.h> #include <asm/smp.h> #include <asm/nmi.h> @@ -41,6 +42,8 @@ int panic_on_unrecovered_nmi; static DEFINE_PER_CPU(unsigned, perfctr_nmi_owner); static DEFINE_PER_CPU(unsigned, evntsel_nmi_owner[2]); +static cpumask_t backtrace_mask = CPU_MASK_NONE; + /* this number is calculated from Intel's MSR_P4_CRU_ESCR5 register and it's * offset from MSR_P4_BSU_ESCR0. It will be the max for all platforms (for now) */ @@ -782,6 +785,7 @@ int __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) { int sum; int touched = 0; + int cpu = smp_processor_id(); struct nmi_watchdog_ctlblk *wd = &__get_cpu_var(nmi_watchdog_ctlblk); u64 dummy; int rc=0; @@ -799,6 +803,16 @@ int __kprobes nmi_watchdog_tick(struct pt_regs * regs, unsigned reason) 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); + } + #ifdef CONFIG_X86_MCE /* Could check oops_in_progress here too, but it's safer not too */ @@ -931,6 +945,19 @@ int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file, #endif +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); EXPORT_SYMBOL(avail_to_resrv_perfctr_nmi); diff --git a/include/asm-i386/nmi.h b/include/asm-i386/nmi.h index 269d315719ca..b04333ea6f31 100644 --- a/include/asm-i386/nmi.h +++ b/include/asm-i386/nmi.h @@ -5,6 +5,9 @@ #define ASM_NMI_H #include <linux/pm.h> +#include <asm/irq.h> + +#ifdef ARCH_HAS_NMI_WATCHDOG /** * do_nmi_callback @@ -42,4 +45,9 @@ extern int proc_nmi_enabled(struct ctl_table *, int , struct file *, void __user *, size_t *, loff_t *); extern int unknown_nmi_panic; +void __trigger_all_cpu_backtrace(void); +#define trigger_all_cpu_backtrace() __trigger_all_cpu_backtrace() + +#endif + #endif /* ASM_NMI_H */ diff --git a/include/asm-x86_64/nmi.h b/include/asm-x86_64/nmi.h index f367d4014b42..72375e7d32a8 100644 --- a/include/asm-x86_64/nmi.h +++ b/include/asm-x86_64/nmi.h @@ -77,4 +77,7 @@ extern int proc_nmi_enabled(struct ctl_table *, int , struct file *, extern int unknown_nmi_panic; +void __trigger_all_cpu_backtrace(void); +#define trigger_all_cpu_backtrace() __trigger_all_cpu_backtrace() + #endif /* ASM_NMI_H */ diff --git a/include/linux/nmi.h b/include/linux/nmi.h index e16904e28c3a..acb4ed130247 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -15,9 +15,14 @@ * disables interrupts for a long time. This call is stateless. */ #ifdef ARCH_HAS_NMI_WATCHDOG +#include <asm/nmi.h> extern void touch_nmi_watchdog(void); #else # define touch_nmi_watchdog() touch_softlockup_watchdog() #endif +#ifndef trigger_all_cpu_backtrace +#define trigger_all_cpu_backtrace() do { } while (0) +#endif + #endif diff --git a/lib/spinlock_debug.c b/lib/spinlock_debug.c index b6c4f898197c..479fd462eaa9 100644 --- a/lib/spinlock_debug.c +++ b/lib/spinlock_debug.c @@ -7,6 +7,7 @@ */ #include <linux/spinlock.h> +#include <linux/nmi.h> #include <linux/interrupt.h> #include <linux/debug_locks.h> #include <linux/delay.h> @@ -117,6 +118,9 @@ static void __spin_lock_debug(spinlock_t *lock) raw_smp_processor_id(), current->comm, current->pid, lock); dump_stack(); +#ifdef CONFIG_SMP + trigger_all_cpu_backtrace(); +#endif } } } |