diff options
| -rw-r--r-- | kernel/cpu.c | 9 | ||||
| -rw-r--r-- | kernel/smp.c | 4 | ||||
| -rw-r--r-- | kernel/smpboot.c | 72 | ||||
| -rw-r--r-- | kernel/smpboot.h | 2 |
4 files changed, 31 insertions, 56 deletions
diff --git a/kernel/cpu.c b/kernel/cpu.c index 05c46bae5e5..0e6353cf147 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -297,15 +297,18 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) int ret, nr_calls = 0; void *hcpu = (void *)(long)cpu; unsigned long mod = tasks_frozen ? CPU_TASKS_FROZEN : 0; + struct task_struct *idle; if (cpu_online(cpu) || !cpu_present(cpu)) return -EINVAL; cpu_hotplug_begin(); - ret = smpboot_prepare(cpu); - if (ret) + idle = idle_thread_get(cpu); + if (IS_ERR(idle)) { + ret = PTR_ERR(idle); goto out; + } ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls); if (ret) { @@ -316,7 +319,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen) } /* Arch-specific enabling code. */ - ret = __cpu_up(cpu, idle_thread_get(cpu)); + ret = __cpu_up(cpu, idle); if (ret != 0) goto out_notify; BUG_ON(!cpu_online(cpu)); diff --git a/kernel/smp.c b/kernel/smp.c index 2f8b10ecf75..a61294c07f3 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -13,6 +13,8 @@ #include <linux/smp.h> #include <linux/cpu.h> +#include "smpboot.h" + #ifdef CONFIG_USE_GENERIC_SMP_HELPERS static struct { struct list_head queue; @@ -669,6 +671,8 @@ void __init smp_init(void) { unsigned int cpu; + idle_threads_init(); + /* FIXME: This should be done in userspace --RR */ for_each_present_cpu(cpu) { if (num_online_cpus() >= setup_max_cpus) diff --git a/kernel/smpboot.c b/kernel/smpboot.c index ed157698180..e1a797e028a 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); -} diff --git a/kernel/smpboot.h b/kernel/smpboot.h index 7943bbbab91..4cfbcb8a836 100644 --- a/kernel/smpboot.h +++ b/kernel/smpboot.h @@ -8,9 +8,11 @@ int smpboot_prepare(unsigned int cpu); #ifdef CONFIG_GENERIC_SMP_IDLE_THREAD struct task_struct *idle_thread_get(unsigned int cpu); void idle_thread_set_boot_cpu(void); +void idle_threads_init(void); #else static inline struct task_struct *idle_thread_get(unsigned int cpu) { return NULL; } static inline void idle_thread_set_boot_cpu(void) { } +static inline void idle_threads_init(unsigned int cpu) { } #endif #endif |