sched: add new API sched_setscheduler_nocheck: add a flag to control access checks

[linux-2.6-omap-h63xx.git] / kernel / softirq.c

diff --git a/kernel/softirq.c b/kernel/softirq.c
index 3c44956ee7e2312d30f28bc68a5b9825a7da657a..afd9120c2fc41b9fbf0ac2caba469eff39b95e87 100644 (file)
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -589,16 +589,20 @@ static void takeover_tasklets(unsigned int cpu)
        local_irq_disable();
 
        /* Find end, append list for that CPU. */
-       *__get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).head;
-       __get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).tail;
-       per_cpu(tasklet_vec, cpu).head = NULL;
-       per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head;
+       if (&per_cpu(tasklet_vec, cpu).head != per_cpu(tasklet_vec, cpu).tail) {
+               *(__get_cpu_var(tasklet_vec).tail) = per_cpu(tasklet_vec, cpu).head;
+               __get_cpu_var(tasklet_vec).tail = per_cpu(tasklet_vec, cpu).tail;
+               per_cpu(tasklet_vec, cpu).head = NULL;
+               per_cpu(tasklet_vec, cpu).tail = &per_cpu(tasklet_vec, cpu).head;
+       }
        raise_softirq_irqoff(TASKLET_SOFTIRQ);
 
-       *__get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).head;
-       __get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).tail;
-       per_cpu(tasklet_hi_vec, cpu).head = NULL;
-       per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head;
+       if (&per_cpu(tasklet_hi_vec, cpu).head != per_cpu(tasklet_hi_vec, cpu).tail) {
+               *__get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).head;
+               __get_cpu_var(tasklet_hi_vec).tail = per_cpu(tasklet_hi_vec, cpu).tail;
+               per_cpu(tasklet_hi_vec, cpu).head = NULL;
+               per_cpu(tasklet_hi_vec, cpu).tail = &per_cpu(tasklet_hi_vec, cpu).head;
+       }
        raise_softirq_irqoff(HI_SOFTIRQ);
 
        local_irq_enable();
@@ -641,7 +645,7 @@ static int __cpuinit cpu_callback(struct notifier_block *nfb,
 
                p = per_cpu(ksoftirqd, hotcpu);
                per_cpu(ksoftirqd, hotcpu) = NULL;
-               sched_setscheduler(p, SCHED_FIFO, &param);
+               sched_setscheduler_nocheck(p, SCHED_FIFO, &param);
                kthread_stop(p);
                takeover_tasklets(hotcpu);
                break;