static void crash_kexec_prepare_cpus(int cpu) { unsigned int msecs; unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ crash_send_ipi(crash_ipi_callback); smp_wmb(); printk(KERN_EMERG "Sending IPI to other cpus...\n"); msecs = 10000; while ((cpus_weight(cpus_in_crash) < ncpus) && (--msecs > 0)) { cpu_relax(); mdelay(1); } /* Would it be better to replace the trap vector here? */ if (cpus_weight(cpus_in_crash) < ncpus) { printk(KERN_EMERG "done waiting: %d cpu(s) not responding\n", ncpus - cpus_weight(cpus_in_crash)); printk(KERN_EMERG "Activate soft-reset to stop other cpu(s)\n"); cpus_in_sr = CPU_MASK_NONE; atomic_set(&enter_on_soft_reset, 0); while (cpus_weight(cpus_in_crash) < ncpus) cpu_relax(); } /* * Make sure all CPUs are entered via soft-reset if the kdump is * invoked using soft-reset. */ if (cpu_isset(cpu, cpus_in_sr)) crash_soft_reset_check(cpu); /* Leave the IPI callback set */ }
static void crash_kexec_prepare_cpus(int cpu) { unsigned int msecs; unsigned int ncpus = num_online_cpus() - 1;/* Excluding the panic cpu */ crash_send_ipi(crash_ipi_callback); smp_wmb(); /* * FIXME: Until we will have the way to stop other CPUSs reliabally, * the crash CPU will send an IPI and wait for other CPUs to * respond. * Delay of at least 10 seconds. */ printk(KERN_EMERG "Sending IPI to other cpus...\n"); msecs = 10000; while ((cpus_weight(cpus_in_crash) < ncpus) && (--msecs > 0)) { cpu_relax(); mdelay(1); } /* Would it be better to replace the trap vector here? */ /* * FIXME: In case if we do not get all CPUs, one possibility: ask the * user to do soft reset such that we get all. * Soft-reset will be used until better mechanism is implemented. */ if (cpus_weight(cpus_in_crash) < ncpus) { printk(KERN_EMERG "done waiting: %d cpu(s) not responding\n", ncpus - cpus_weight(cpus_in_crash)); printk(KERN_EMERG "Activate soft-reset to stop other cpu(s)\n"); cpus_in_sr = CPU_MASK_NONE; atomic_set(&enter_on_soft_reset, 0); while (cpus_weight(cpus_in_crash) < ncpus) cpu_relax(); } /* * Make sure all CPUs are entered via soft-reset if the kdump is * invoked using soft-reset. */ if (cpu_isset(cpu, cpus_in_sr)) crash_soft_reset_check(cpu); /* Leave the IPI callback set */ }
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 * respond. */ msecs = IPI_TIMEOUT; while ((atomic_read(&cpus_in_crash) < ncpus) && (--msecs > 0)) mdelay(1); /* Would it be better to replace the trap vector here? */ if (atomic_read(&cpus_in_crash) >= ncpus) { printk(KERN_EMERG "IPI complete\n"); return; } printk(KERN_EMERG "ERROR: %d cpu(s) not responding\n", ncpus - atomic_read(&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. */ atomic_set(&cpus_in_crash, 0); smp_mb(); while (atomic_read(&cpus_in_crash) < ncpus) cpu_relax(); } crash_shutdown_cpu = -1; __debugger = old_handler; tries++; goto again; }