[PATCH] convert kernel/rcupdate.c:rcu_barrier_sema to mutex
Convert kernel/rcupdate's rcu_barrier_sema to mutex.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index fedf5e3..af8a2a5 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -47,6 +47,7 @@
#include <linux/notifier.h>
#include <linux/rcupdate.h>
#include <linux/cpu.h>
+#include <linux/mutex.h>
/* Definition for rcupdate control block. */
struct rcu_ctrlblk rcu_ctrlblk = {
@@ -75,7 +76,7 @@
#endif
static atomic_t rcu_barrier_cpu_count;
-static struct semaphore rcu_barrier_sema;
+static DEFINE_MUTEX(rcu_barrier_mutex);
static struct completion rcu_barrier_completion;
#ifdef CONFIG_SMP
@@ -207,13 +208,13 @@
void rcu_barrier(void)
{
BUG_ON(in_interrupt());
- /* Take cpucontrol semaphore to protect against CPU hotplug */
- down(&rcu_barrier_sema);
+ /* Take cpucontrol mutex to protect against CPU hotplug */
+ mutex_lock(&rcu_barrier_mutex);
init_completion(&rcu_barrier_completion);
atomic_set(&rcu_barrier_cpu_count, 0);
on_each_cpu(rcu_barrier_func, NULL, 0, 1);
wait_for_completion(&rcu_barrier_completion);
- up(&rcu_barrier_sema);
+ mutex_unlock(&rcu_barrier_mutex);
}
EXPORT_SYMBOL_GPL(rcu_barrier);
@@ -549,7 +550,6 @@
*/
void __init rcu_init(void)
{
- sema_init(&rcu_barrier_sema, 1);
rcu_cpu_notify(&rcu_nb, CPU_UP_PREPARE,
(void *)(long)smp_processor_id());
/* Register notifier for non-boot CPUs */