diff options
-rw-r--r-- | kernel/sys.c | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/kernel/sys.c b/kernel/sys.c index b95d3c72ba21..2bbd9a73b54c 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -362,6 +362,29 @@ int unregister_reboot_notifier(struct notifier_block *nb) } EXPORT_SYMBOL(unregister_reboot_notifier); +/* Add backwards compatibility for stable trees. */ +#ifndef PF_NO_SETAFFINITY +#define PF_NO_SETAFFINITY PF_THREAD_BOUND +#endif + +static void migrate_to_reboot_cpu(void) +{ + /* The boot cpu is always logical cpu 0 */ + int cpu = 0; + + cpu_hotplug_disable(); + + /* Make certain the cpu I'm about to reboot on is online */ + if (!cpu_online(cpu)) + cpu = cpumask_first(cpu_online_mask); + + /* Prevent races with other tasks migrating this task */ + current->flags |= PF_NO_SETAFFINITY; + + /* Make certain I only run on the appropriate processor */ + set_cpus_allowed_ptr(current, cpumask_of(cpu)); +} + /** * kernel_restart - reboot the system * @cmd: pointer to buffer containing command to execute for restart @@ -373,7 +396,7 @@ EXPORT_SYMBOL(unregister_reboot_notifier); void kernel_restart(char *cmd) { kernel_restart_prepare(cmd); - disable_nonboot_cpus(); + migrate_to_reboot_cpu(); syscore_shutdown(); if (!cmd) printk(KERN_EMERG "Restarting system.\n"); @@ -400,7 +423,7 @@ static void kernel_shutdown_prepare(enum system_states state) void kernel_halt(void) { kernel_shutdown_prepare(SYSTEM_HALT); - disable_nonboot_cpus(); + migrate_to_reboot_cpu(); syscore_shutdown(); printk(KERN_EMERG "System halted.\n"); kmsg_dump(KMSG_DUMP_HALT); @@ -419,7 +442,7 @@ void kernel_power_off(void) kernel_shutdown_prepare(SYSTEM_POWER_OFF); if (pm_power_off_prepare) pm_power_off_prepare(); - disable_nonboot_cpus(); + migrate_to_reboot_cpu(); syscore_shutdown(); printk(KERN_EMERG "Power down.\n"); kmsg_dump(KMSG_DUMP_POWEROFF); |