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Subject[PATCH 4/5] powerpc: Use common fork_idle_from_wq in smpboot
Date
Cleanup. Instead of reimplementing fork_idle on wq and idle task caching,
use fork_idle_from_wq().

Signed-off-by: Venkatesh Pallipadi <venki@google.com>
---
arch/powerpc/kernel/smp.c | 63 +++++---------------------------------------
1 files changed, 8 insertions(+), 55 deletions(-)
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 46695fe..3b9705d 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -57,27 +57,11 @@
#define DBG(fmt...)
#endif

-
-/* Store all idle threads, this can be reused instead of creating
-* a new thread. Also avoids complicated thread destroy functionality
-* for idle threads.
-*/
#ifdef CONFIG_HOTPLUG_CPU
-/*
- * Needed only for CONFIG_HOTPLUG_CPU because __cpuinitdata is
- * removed after init for !CONFIG_HOTPLUG_CPU.
- */
-static DEFINE_PER_CPU(struct task_struct *, idle_thread_array);
-#define get_idle_for_cpu(x) (per_cpu(idle_thread_array, x))
-#define set_idle_for_cpu(x, p) (per_cpu(idle_thread_array, x) = (p))

/* State of each CPU during hotplug phases */
static DEFINE_PER_CPU(int, cpu_state) = { 0 };

-#else
-static struct task_struct *idle_thread_array[NR_CPUS] __cpuinitdata ;
-#define get_idle_for_cpu(x) (idle_thread_array[(x)])
-#define set_idle_for_cpu(x, p) (idle_thread_array[(x)] = (p))
#endif

struct thread_info *secondary_ti;
@@ -429,51 +413,20 @@ int generic_check_cpu_restart(unsigned int cpu)
}
#endif

-struct create_idle {
- struct work_struct work;
- struct task_struct *idle;
- struct completion done;
- int cpu;
-};
-
-static void __cpuinit do_fork_idle(struct work_struct *work)
-{
- struct create_idle *c_idle =
- container_of(work, struct create_idle, work);
-
- c_idle->idle = fork_idle(c_idle->cpu);
- complete(&c_idle->done);
-}
-
static int __cpuinit create_idle(unsigned int cpu)
{
struct thread_info *ti;
- struct create_idle c_idle = {
- .cpu = cpu,
- .done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done),
- };
- INIT_WORK_ONSTACK(&c_idle.work, do_fork_idle);
-
- c_idle.idle = get_idle_for_cpu(cpu);
-
- /* We can't use kernel_thread since we must avoid to
- * reschedule the child. We use a workqueue because
- * we want to fork from a kernel thread, not whatever
- * userspace process happens to be trying to online us.
- */
- if (!c_idle.idle) {
- schedule_work(&c_idle.work);
- wait_for_completion(&c_idle.done);
- } else
- init_idle(c_idle.idle, cpu);
- if (IS_ERR(c_idle.idle)) {
- pr_err("Failed fork for CPU %u: %li", cpu, PTR_ERR(c_idle.idle));
- return PTR_ERR(c_idle.idle);
+ struct task_struct *idle;
+
+ idle = fork_idle_from_wq(cpu);
+ if (IS_ERR(idle)) {
+ pr_err("Failed fork for CPU %u: %li", cpu, PTR_ERR(idle));
+ return PTR_ERR(idle);
}
- ti = task_thread_info(c_idle.idle);
+ ti = task_thread_info(idle);

#ifdef CONFIG_PPC64
- paca[cpu].__current = c_idle.idle;
+ paca[cpu].__current = idle;
paca[cpu].kstack = (unsigned long)ti + THREAD_SIZE - STACK_FRAME_OVERHEAD;
#endif
ti->cpu = cpu;
--
1.7.7.3


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