diff options
Diffstat (limited to 'arch/i386/kernel/crash.c')
| -rw-r--r-- | arch/i386/kernel/crash.c | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/arch/i386/kernel/crash.c b/arch/i386/kernel/crash.c index fa27a6c..882779c 100644 --- a/arch/i386/kernel/crash.c +++ b/arch/i386/kernel/crash.c @@ -23,12 +23,65 @@ #include <asm/hardirq.h> #include <asm/nmi.h> #include <asm/hw_irq.h> +#include <mach_ipi.h> #define MAX_NOTE_BYTES 1024 typedef u32 note_buf_t[MAX_NOTE_BYTES/4]; note_buf_t crash_notes[NR_CPUS]; +#ifdef CONFIG_SMP +static atomic_t waiting_for_crash_ipi; + +static int crash_nmi_callback(struct pt_regs *regs, int cpu) +{ + local_irq_disable(); + atomic_dec(&waiting_for_crash_ipi); + /* Assume hlt works */ + __asm__("hlt"); + for(;;); + return 1; +} + +/* + * By using the NMI code instead of a vector we just sneak thru the + * word generator coming out with just what we want. AND it does + * not matter if clustered_apic_mode is set or not. + */ +static void smp_send_nmi_allbutself(void) +{ + send_IPI_allbutself(APIC_DM_NMI); +} + +static void nmi_shootdown_cpus(void) +{ + unsigned long msecs; + atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); + + /* Would it be better to replace the trap vector here? */ + set_nmi_callback(crash_nmi_callback); + /* Ensure the new callback function is set before sending + * out the NMI + */ + wmb(); + + smp_send_nmi_allbutself(); + + msecs = 1000; /* Wait at most a second for the other cpus to stop */ + while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { + mdelay(1); + msecs--; + } + + /* Leave the nmi callback set */ +} +#else +static void nmi_shootdown_cpus(void) +{ + /* There are no cpus to shootdown */ +} +#endif + void machine_crash_shutdown(void) { /* This function is only called after the system @@ -39,4 +92,7 @@ void machine_crash_shutdown(void) * In practice this means shooting down the other cpus in * an SMP system. */ + /* The kernel is broken so disable interrupts */ + local_irq_disable(); + nmi_shootdown_cpus(); } |