rcu: Switch to this_cpu() primitives

This removes a couple of lines from invoke_rcu_cpu_kthread(), improving
readability.

Reported-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

1 files changed, 3 insertions, 7 deletions

diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 575d6414763e..27304bc15eca 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -1480,18 +1480,14 @@ static void rcu_process_callbacks(void)
 static void invoke_rcu_cpu_kthread(void)
 {
         unsigned long flags;
-        wait_queue_head_t *q;
-        int cpu;
 
         local_irq_save(flags);
-        cpu = smp_processor_id();
-        per_cpu(rcu_cpu_has_work, cpu) = 1;
-        if (per_cpu(rcu_cpu_kthread_task, cpu) == NULL) {
+        __this_cpu_write(rcu_cpu_has_work, 1);
+        if (__this_cpu_read(rcu_cpu_kthread_task) == NULL) {
                 local_irq_restore(flags);
                 return;
         }
-        q = &per_cpu(rcu_cpu_wq, cpu);
-        wake_up(q);
+        wake_up(&__get_cpu_var(rcu_cpu_wq));
         local_irq_restore(flags);
 }