#include <linux/kernel.h> #include <linux/smp.h> #include <linux/reboot.h> #include <linux/kexec.h> #include <linux/bootmem.h> #include <linux/crash_dump.h> #include <linux/delay.h> #include <linux/irq.h> #include <linux/types.h> #include <linux/sched.h> /* This keeps a track of which one is crashing cpu. */ static int crashing_cpu = -1; static cpumask_t cpus_in_crash = CPU_MASK_NONE; #ifdef CONFIG_SMP static void crash_shutdown_secondary(void *ignore) { struct pt_regs *regs; int cpu = smp_processor_id(); regs = task_pt_regs(current); if (!cpu_online(cpu)) return; local_irq_disable(); if (!cpu_isset(cpu, cpus_in_crash)) crash_save_cpu(regs, cpu); cpu_set(cpu, cpus_in_crash); while (!atomic_read(&kexec_ready_to_reboot)) cpu_relax(); relocated_kexec_smp_wait(NULL); /* NOTREACHED */ } static void crash_kexec_prepare_cpus(void) { unsigned int msecs; unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ dump_send_ipi(crash_shutdown_secondary); smp_wmb(); /* * The crash CPU sends an IPI and wait for other CPUs to * respond. Delay of at least 10 seconds. */ pr_emerg("Sending IPI to other cpus...\n"); msecs = 10000; while ((cpus_weight(cpus_in_crash) < ncpus) && (--msecs > 0)) { cpu_relax(); mdelay(1); } } #else /* !defined(CONFIG_SMP) */ static void crash_kexec_prepare_cpus(void) {} #endif /* !defined(CONFIG_SMP) */ void default_machine_crash_shutdown(struct pt_regs *regs) { local_irq_disable(); crashing_cpu = smp_processor_id(); crash_save_cpu(regs, crashing_cpu); crash_kexec_prepare_cpus(); cpu_set(crashing_cpu, cpus_in_crash); }