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-rw-r--r--kernel/smpboot.c72
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);
-}