diff options
| -rw-r--r-- | arch/arm/include/asm/hardirq.h | 2 | ||||
| -rw-r--r-- | arch/arm/include/asm/irq.h | 3 | ||||
| -rw-r--r-- | arch/arm/include/asm/smp.h | 2 | ||||
| -rw-r--r-- | arch/arm/kernel/process.c | 12 | ||||
| -rw-r--r-- | arch/arm/kernel/smp.c | 58 |
5 files changed, 76 insertions, 1 deletions
diff --git a/arch/arm/include/asm/hardirq.h b/arch/arm/include/asm/hardirq.h index 89ad1805e579..2635c8b5bf59 100644 --- a/arch/arm/include/asm/hardirq.h +++ b/arch/arm/include/asm/hardirq.h @@ -5,7 +5,7 @@ #include <linux/threads.h> #include <asm/irq.h> -#define NR_IPI 5 +#define NR_IPI 6 typedef struct { unsigned int __softirq_pending; diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h index 5a526afb5f18..a5656333d574 100644 --- a/arch/arm/include/asm/irq.h +++ b/arch/arm/include/asm/irq.h @@ -26,6 +26,9 @@ extern void asm_do_IRQ(unsigned int, struct pt_regs *); void handle_IRQ(unsigned int, struct pt_regs *); void init_IRQ(void); +void arch_trigger_all_cpu_backtrace(void); +#define arch_trigger_all_cpu_backtrace arch_trigger_all_cpu_backtrace + #endif #endif diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h index e42d96a45d3e..74f288f4802c 100644 --- a/arch/arm/include/asm/smp.h +++ b/arch/arm/include/asm/smp.h @@ -93,4 +93,6 @@ extern void arch_send_call_function_ipi_mask(const struct cpumask *mask); */ extern void show_local_irqs(struct seq_file *, int); +extern void smp_send_all_cpu_backtrace(void); + #endif /* ifndef __ASM_ARM_SMP_H */ diff --git a/arch/arm/kernel/process.c b/arch/arm/kernel/process.c index 24e7e5722f1c..5360757e902f 100644 --- a/arch/arm/kernel/process.c +++ b/arch/arm/kernel/process.c @@ -63,6 +63,18 @@ static volatile int hlt_counter; #include <mach/system.h> +#ifdef CONFIG_SMP +void arch_trigger_all_cpu_backtrace(void) +{ + smp_send_all_cpu_backtrace(); +} +#else +void arch_trigger_all_cpu_backtrace(void) +{ + dump_stack(); +} +#endif + void disable_hlt(void) { hlt_counter++; diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index d88ff0230e82..4be92bc9b779 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -53,6 +53,7 @@ enum ipi_msg_type { IPI_CALL_FUNC, IPI_CALL_FUNC_SINGLE, IPI_CPU_STOP, + IPI_CPU_BACKTRACE, }; int __cpuinit __cpu_up(unsigned int cpu) @@ -412,6 +413,7 @@ static const char *ipi_types[NR_IPI] = { S(IPI_CALL_FUNC, "Function call interrupts"), S(IPI_CALL_FUNC_SINGLE, "Single function call interrupts"), S(IPI_CPU_STOP, "CPU stop interrupts"), + S(IPI_CPU_BACKTRACE, "CPU backtrace"), }; void show_ipi_list(struct seq_file *p, int prec) @@ -562,6 +564,58 @@ static void ipi_cpu_stop(unsigned int cpu) cpu_relax(); } +static cpumask_t backtrace_mask; +static DEFINE_RAW_SPINLOCK(backtrace_lock); + +/* "in progress" flag of arch_trigger_all_cpu_backtrace */ +static unsigned long backtrace_flag; + +void smp_send_all_cpu_backtrace(void) +{ + unsigned int this_cpu = smp_processor_id(); + int i; + + if (test_and_set_bit(0, &backtrace_flag)) + /* + * If there is already a trigger_all_cpu_backtrace() in progress + * (backtrace_flag == 1), don't output double cpu dump infos. + */ + return; + + cpumask_copy(&backtrace_mask, cpu_online_mask); + cpu_clear(this_cpu, backtrace_mask); + + pr_info("Backtrace for cpu %d (current):\n", this_cpu); + dump_stack(); + + pr_info("\nsending IPI to all other CPUs:\n"); + smp_cross_call(&backtrace_mask, IPI_CPU_BACKTRACE); + + /* Wait for up to 10 seconds for all other CPUs to do the backtrace */ + for (i = 0; i < 10 * 1000; i++) { + if (cpumask_empty(&backtrace_mask)) + break; + mdelay(1); + } + + clear_bit(0, &backtrace_flag); + smp_mb__after_clear_bit(); +} + +/* + * ipi_cpu_backtrace - handle IPI from smp_send_all_cpu_backtrace() + */ +static void ipi_cpu_backtrace(unsigned int cpu, struct pt_regs *regs) +{ + if (cpu_isset(cpu, backtrace_mask)) { + raw_spin_lock(&backtrace_lock); + pr_warning("IPI backtrace for cpu %d\n", cpu); + show_regs(regs); + raw_spin_unlock(&backtrace_lock); + cpu_clear(cpu, backtrace_mask); + } +} + /* * Main handler for inter-processor interrupts */ @@ -594,6 +648,10 @@ asmlinkage void __exception_irq_entry do_IPI(int ipinr, struct pt_regs *regs) ipi_cpu_stop(cpu); break; + case IPI_CPU_BACKTRACE: + ipi_cpu_backtrace(cpu, regs); + break; + default: printk(KERN_CRIT "CPU%u: Unknown IPI message 0x%x\n", cpu, ipinr); |