cpu-hotplug-provide-a-generic-helper-to-disable-enable-cpu-hotplug-v11

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/include/linux/cpu.h b/include/linux/cpu.h
index 73f02a3e6ab74cbb2a0173fdbd91153cac2e15dd..9f3c7e81270ad11c18fdbfdec42416058560af7f 100644 (file)
--- a/include/linux/cpu.h
+++ b/include/linux/cpu.h
@@ -168,20 +168,6 @@ static inline void cpu_maps_update_done(void)
 }
 
 #endif /* CONFIG_SMP */
-
-#ifdef CONFIG_PM_SLEEP_SMP
-extern void cpu_hotplug_enable(void);
-extern void cpu_hotplug_disable(void);
-#else
-static inline void cpu_hotplug_enable(void)
-{
-}
-
-static inline void cpu_hotplug_disable(void)
-{
-}
-#endif
-
 extern struct bus_type cpu_subsys;
 
 #ifdef CONFIG_HOTPLUG_CPU
@@ -189,6 +175,8 @@ extern struct bus_type cpu_subsys;
 
 extern void get_online_cpus(void);
 extern void put_online_cpus(void);
+extern void cpu_hotplug_disable(void);
+extern void cpu_hotplug_enable(void);
 #define hotcpu_notifier(fn, pri)       cpu_notifier(fn, pri)
 #define register_hotcpu_notifier(nb)   register_cpu_notifier(nb)
 #define unregister_hotcpu_notifier(nb) unregister_cpu_notifier(nb)
@@ -212,6 +200,8 @@ static inline void cpu_hotplug_driver_unlock(void)
 
 #define get_online_cpus()      do { } while (0)
 #define put_online_cpus()      do { } while (0)
+#define cpu_hotplug_disable()  do { } while (0)
+#define cpu_hotplug_enable()   do { } while (0)
 #define hotcpu_notifier(fn, pri)       do { (void)(fn); } while (0)
 /* These aren't inline functions due to a GCC bug. */
 #define register_hotcpu_notifier(nb)   ({ (void)(nb); 0; })

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 28769f5ca9a45bc920b1b99e7fc94e8a4a69c60b..198a38883e64a0616437401ef2692f5b3c9029a5 100644 (file)
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -133,6 +133,27 @@ static void cpu_hotplug_done(void)
        mutex_unlock(&cpu_hotplug.lock);
 }
 
+/*
+ * Wait for currently running CPU hotplug operations to complete (if any) and
+ * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects
+ * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the
+ * hotplug path before performing hotplug operations. So acquiring that lock
+ * guarantees mutual exclusion from any currently running hotplug operations.
+ */
+void cpu_hotplug_disable(void)
+{
+       cpu_maps_update_begin();
+       cpu_hotplug_disabled = 1;
+       cpu_maps_update_done();
+}
+
+void cpu_hotplug_enable(void)
+{
+       cpu_maps_update_begin();
+       cpu_hotplug_disabled = 0;
+       cpu_maps_update_done();
+}
+
 #else /* #if CONFIG_HOTPLUG_CPU */
 static void cpu_hotplug_begin(void) {}
 static void cpu_hotplug_done(void) {}
@@ -540,27 +561,6 @@ static int __init alloc_frozen_cpus(void)
 }
 core_initcall(alloc_frozen_cpus);
 
-/*
- * Wait for currently running CPU hotplug operations to complete (if any) and
- * disable future CPU hotplug (from sysfs). The 'cpu_add_remove_lock' protects
- * the 'cpu_hotplug_disabled' flag. The same lock is also acquired by the
- * hotplug path before performing hotplug operations. So acquiring that lock
- * guarantees mutual exclusion from any currently running hotplug operations.
- */
-void cpu_hotplug_disable(void)
-{
-       cpu_maps_update_begin();
-       cpu_hotplug_disabled = 1;
-       cpu_maps_update_done();
-}
-
-void cpu_hotplug_enable(void)
-{
-       cpu_maps_update_begin();
-       cpu_hotplug_disabled = 0;
-       cpu_maps_update_done();
-}
-
 /*
  * When callbacks for CPU hotplug notifications are being executed, we must
  * ensure that the state of the system with respect to the tasks being frozen