Merge tag 'v2.6.38' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[mv-sheeva.git] / arch / s390 / kernel / smp.c

diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 94cf510b8fe181850e36acdeaa8a9fa65b1397b7..63a97db83f96337013bfeeaf7cb7369a58d2a60f 100644 (file)
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -23,6 +23,7 @@
 #define KMSG_COMPONENT "cpu"
 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
 
+#include <linux/workqueue.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/mm.h>
@@ -161,6 +162,7 @@ static void do_ext_call_interrupt(unsigned int ext_int_code,
 {
        unsigned long bits;
 
+       kstat_cpu(smp_processor_id()).irqs[EXTINT_IPI]++;
        /*
         * handle bit signal external calls
         *
@@ -469,25 +471,25 @@ int __cpuinit start_secondary(void *cpuvoid)
        ipi_call_unlock();
        /* Switch on interrupts */
        local_irq_enable();
-       /* Print info about this processor */
-       print_cpu_info();
        /* cpu_idle will call schedule for us */
        cpu_idle();
        return 0;
 }
 
-static void __init smp_create_idle(unsigned int cpu)
+struct create_idle {
+       struct work_struct work;
+       struct task_struct *idle;
+       struct completion done;
+       int cpu;
+};
+
+static void __cpuinit smp_fork_idle(struct work_struct *work)
 {
-       struct task_struct *p;
+       struct create_idle *c_idle;
 
-       /*
-        *  don't care about the psw and regs settings since we'll never
-        *  reschedule the forked task.
-        */
-       p = fork_idle(cpu);
-       if (IS_ERR(p))
-               panic("failed fork for CPU %u: %li", cpu, PTR_ERR(p));
-       current_set[cpu] = p;
+       c_idle = container_of(work, struct create_idle, work);
+       c_idle->idle = fork_idle(c_idle->cpu);
+       complete(&c_idle->done);
 }
 
 static int __cpuinit smp_alloc_lowcore(int cpu)
@@ -551,6 +553,7 @@ static void smp_free_lowcore(int cpu)
 int __cpuinit __cpu_up(unsigned int cpu)
 {
        struct _lowcore *cpu_lowcore;
+       struct create_idle c_idle;
        struct task_struct *idle;
        struct stack_frame *sf;
        u32 lowcore;
@@ -558,6 +561,19 @@ int __cpuinit __cpu_up(unsigned int cpu)
 
        if (smp_cpu_state[cpu] != CPU_STATE_CONFIGURED)
                return -EIO;
+       idle = current_set[cpu];
+       if (!idle) {
+               c_idle.done = COMPLETION_INITIALIZER_ONSTACK(c_idle.done);
+               INIT_WORK_ONSTACK(&c_idle.work, smp_fork_idle);
+               c_idle.cpu = cpu;
+               schedule_work(&c_idle.work);
+               wait_for_completion(&c_idle.done);
+               if (IS_ERR(c_idle.idle))
+                       return PTR_ERR(c_idle.idle);
+               idle = c_idle.idle;
+               current_set[cpu] = c_idle.idle;
+       }
+       init_idle(idle, cpu);
        if (smp_alloc_lowcore(cpu))
                return -ENOMEM;
        do {
@@ -572,7 +588,6 @@ int __cpuinit __cpu_up(unsigned int cpu)
        while (sigp_p(lowcore, cpu, sigp_set_prefix) == sigp_busy)
                udelay(10);
 
-       idle = current_set[cpu];
        cpu_lowcore = lowcore_ptr[cpu];
        cpu_lowcore->kernel_stack = (unsigned long)
                task_stack_page(idle) + THREAD_SIZE;
@@ -664,7 +679,6 @@ void __cpu_die(unsigned int cpu)
                udelay(10);
        smp_free_lowcore(cpu);
        atomic_dec(&init_mm.context.attach_count);
-       pr_info("Processor %d stopped\n", cpu);
 }
 
 void cpu_die(void)
@@ -684,14 +698,12 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
 #endif
        unsigned long async_stack, panic_stack;
        struct _lowcore *lowcore;
-       unsigned int cpu;
 
        smp_detect_cpus();
 
        /* request the 0x1201 emergency signal external interrupt */
        if (register_external_interrupt(0x1201, do_ext_call_interrupt) != 0)
                panic("Couldn't request external interrupt 0x1201");
-       print_cpu_info();
 
        /* Reallocate current lowcore, but keep its contents. */
        lowcore = (void *) __get_free_pages(GFP_KERNEL | GFP_DMA, LC_ORDER);
@@ -719,9 +731,6 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
        if (vdso_alloc_per_cpu(smp_processor_id(), &S390_lowcore))
                BUG();
 #endif
-       for_each_possible_cpu(cpu)
-               if (cpu != smp_processor_id())
-                       smp_create_idle(cpu);
 }
 
 void __init smp_prepare_boot_cpu(void)