diff options
Diffstat (limited to 'kernel/smpboot.c')
-rw-r--r-- | kernel/smpboot.c | 72 |
1 files changed, 19 insertions, 53 deletions
diff --git a/kernel/smpboot.c b/kernel/smpboot.c index ed1576981801..e1a797e028a3 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -6,64 +6,42 @@ #include <linux/init.h> #include <linux/sched.h> #include <linux/percpu.h> -#include <linux/workqueue.h> #include "smpboot.h" #ifdef CONFIG_GENERIC_SMP_IDLE_THREAD -struct create_idle { - struct work_struct work; - struct task_struct *idle; - struct completion done; - unsigned int cpu; -}; - -static void __cpuinit do_fork_idle(struct work_struct *work) -{ - struct create_idle *c = container_of(work, struct create_idle, work); - - c->idle = fork_idle(c->cpu); - complete(&c->done); -} - -static struct task_struct * __cpuinit idle_thread_create(unsigned int cpu) -{ - struct create_idle c_idle = { - .cpu = cpu, - .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done), - }; - - INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle); - schedule_work(&c_idle.work); - wait_for_completion(&c_idle.done); - destroy_work_on_stack(&c_idle.work); - return c_idle.idle; -} - /* * For the hotplug case we keep the task structs around and reuse * them. */ static DEFINE_PER_CPU(struct task_struct *, idle_threads); -static inline struct task_struct *get_idle_for_cpu(unsigned int cpu) +struct task_struct * __cpuinit idle_thread_get(unsigned int cpu) { struct task_struct *tsk = per_cpu(idle_threads, cpu); if (!tsk) - return idle_thread_create(cpu); + return ERR_PTR(-ENOMEM); init_idle(tsk, cpu); return tsk; } -struct task_struct * __cpuinit idle_thread_get(unsigned int cpu) +void __init idle_thread_set_boot_cpu(void) { - return per_cpu(idle_threads, cpu); + per_cpu(idle_threads, smp_processor_id()) = current; } -void __init idle_thread_set_boot_cpu(void) +static inline void idle_init(unsigned int cpu) { - per_cpu(idle_threads, smp_processor_id()) = current; + struct task_struct *tsk = per_cpu(idle_threads, cpu); + + if (!tsk) { + tsk = fork_idle(cpu); + if (IS_ERR(tsk)) + pr_err("SMP: fork_idle() failed for CPU %u\n", cpu); + else + per_cpu(idle_threads, cpu) = tsk; + } } /** @@ -72,25 +50,13 @@ void __init idle_thread_set_boot_cpu(void) * * Creates the thread if it does not exist. */ -static int __cpuinit idle_thread_init(unsigned int cpu) +void __init idle_threads_init(void) { - struct task_struct *idle = get_idle_for_cpu(cpu); + unsigned int cpu; - if (IS_ERR(idle)) { - printk(KERN_ERR "failed fork for CPU %u\n", cpu); - return PTR_ERR(idle); + for_each_possible_cpu(cpu) { + if (cpu != smp_processor_id()) + idle_init(cpu); } - per_cpu(idle_threads, cpu) = idle; - return 0; } -#else -static inline int idle_thread_init(unsigned int cpu) { return 0; } #endif - -/** - * smpboot_prepare - generic smpboot preparation - */ -int __cpuinit smpboot_prepare(unsigned int cpu) -{ - return idle_thread_init(cpu); -} |