diff options
| -rw-r--r-- | arch/powerpc/kernel/crash.c | 72 |
1 files changed, 57 insertions, 15 deletions
diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c index 3d87b205d5f5..a8b6e2d705a4 100644 --- a/arch/powerpc/kernel/crash.c +++ b/arch/powerpc/kernel/crash.c @@ -53,6 +53,16 @@ static cpumask_t cpus_in_crash = CPU_MASK_NONE; static crash_shutdown_t crash_shutdown_handles[CRASH_HANDLER_MAX+1]; static DEFINE_SPINLOCK(crash_handlers_lock); +static unsigned long crash_shutdown_buf[JMP_BUF_LEN]; +static int crash_shutdown_cpu = -1; + +static int handle_fault(struct pt_regs *regs) +{ + if (crash_shutdown_cpu == smp_processor_id()) + longjmp(crash_shutdown_buf, 1); + return 0; +} + #ifdef CONFIG_SMP void crash_ipi_callback(struct pt_regs *regs) @@ -89,14 +99,16 @@ void crash_ipi_callback(struct pt_regs *regs) static void crash_kexec_prepare_cpus(int cpu) { unsigned int msecs; - unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ + int tries = 0; + int (*old_handler)(struct pt_regs *regs); printk(KERN_EMERG "Sending IPI to other CPUs\n"); crash_send_ipi(crash_ipi_callback); smp_wmb(); +again: /* * FIXME: Until we will have the way to stop other CPUs reliably, * the crash CPU will send an IPI and wait for other CPUs to @@ -111,12 +123,52 @@ static void crash_kexec_prepare_cpus(int cpu) /* Would it be better to replace the trap vector here? */ - if (cpumask_weight(&cpus_in_crash) < ncpus) { - printk(KERN_EMERG "ERROR: %d CPU(s) not responding\n", - ncpus - cpumask_weight(&cpus_in_crash)); + if (cpumask_weight(&cpus_in_crash) >= ncpus) { + printk(KERN_EMERG "IPI complete\n"); + return; + } + + printk(KERN_EMERG "ERROR: %d cpu(s) not responding\n", + ncpus - cpumask_weight(&cpus_in_crash)); + + /* + * If we have a panic timeout set then we can't wait indefinitely + * for someone to activate system reset. We also give up on the + * second time through if system reset fail to work. + */ + if ((panic_timeout > 0) || (tries > 0)) + return; + + /* + * A system reset will cause all CPUs to take an 0x100 exception. + * The primary CPU returns here via setjmp, and the secondary + * CPUs reexecute the crash_kexec_secondary path. + */ + old_handler = __debugger; + __debugger = handle_fault; + crash_shutdown_cpu = smp_processor_id(); + + if (setjmp(crash_shutdown_buf) == 0) { + printk(KERN_EMERG "Activate system reset (dumprestart) " + "to stop other cpu(s)\n"); + + /* + * A system reset will force all CPUs to execute the + * crash code again. We need to reset cpus_in_crash so we + * wait for everyone to do this. + */ + cpus_in_crash = CPU_MASK_NONE; + smp_mb(); + + while (cpumask_weight(&cpus_in_crash) < ncpus) + cpu_relax(); } - printk(KERN_EMERG "IPI complete\n"); + crash_shutdown_cpu = -1; + __debugger = old_handler; + + tries++; + goto again; } /* @@ -245,16 +297,6 @@ int crash_shutdown_unregister(crash_shutdown_t handler) } EXPORT_SYMBOL(crash_shutdown_unregister); -static unsigned long crash_shutdown_buf[JMP_BUF_LEN]; -static int crash_shutdown_cpu = -1; - -static int handle_fault(struct pt_regs *regs) -{ - if (crash_shutdown_cpu == smp_processor_id()) - longjmp(crash_shutdown_buf, 1); - return 0; -} - void default_machine_crash_shutdown(struct pt_regs *regs) { unsigned int i; |