idle-notifier-standardize

4 files changed, 47 insertions, 23 deletions

diff --git a/arch/x86/include/asm/idle.h b/arch/x86/include/asm/idle.h
index 38d87379e27..192e5a02a8c 100644
--- a/arch/x86/include/asm/idle.h
+++ b/arch/x86/include/asm/idle.h
@@ -1,13 +1,6 @@
 #ifndef _ASM_X86_IDLE_H
 #define _ASM_X86_IDLE_H
 
-#define IDLE_START 1
-#define IDLE_END 2
-
-struct notifier_block;
-void idle_notifier_register(struct notifier_block *n);
-void idle_notifier_unregister(struct notifier_block *n);
-
 #ifdef CONFIG_X86_64
 void enter_idle(void);
 void exit_idle(void);
diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 034100e5ade..fbd564ecfdc 100644
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -35,6 +35,7 @@
 #include <linux/tick.h>
 #include <linux/prctl.h>
 #include <linux/uaccess.h>
+#include <linux/idle.h>
 #include <linux/io.h>
 #include <linux/ftrace.h>
 #include <trace/pm.h>
@@ -60,20 +61,6 @@ asmlinkage extern void ret_from_fork(void);
 DEFINE_PER_CPU(unsigned long, old_rsp);
 static DEFINE_PER_CPU(unsigned char, is_idle);
 
-static ATOMIC_NOTIFIER_HEAD(idle_notifier);
-
-void idle_notifier_register(struct notifier_block *n)
-{
-	atomic_notifier_chain_register(&idle_notifier, n);
-}
-EXPORT_SYMBOL_GPL(idle_notifier_register);
-
-void idle_notifier_unregister(struct notifier_block *n)
-{
-	atomic_notifier_chain_unregister(&idle_notifier, n);
-}
-EXPORT_SYMBOL_GPL(idle_notifier_unregister);
-
 void enter_idle(void)
 {
 	percpu_write(is_idle, 1);
@@ -82,14 +69,14 @@ void enter_idle(void)
 	 * data from buffers before going to idle.
 	 */
 	trace_pm_idle_entry();
-	atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL);
+	notify_idle(IDLE_START);
 }
 
 static void __exit_idle(void)
 {
 	if (x86_test_and_clear_bit_percpu(0, is_idle) == 0)
 		return;
-	atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL);
+	notify_idle(IDLE_END);
 	trace_pm_idle_exit();
 }
 
diff --git a/include/linux/idle.h b/include/linux/idle.h
new file mode 100644
index 00000000000..75bd2a422c8
--- /dev/null
+++ b/include/linux/idle.h
@@ -0,0 +1,19 @@
+/*
+ * include/linux/idle.h - generic idle definition
+ *
+ */
+#ifndef _LINUX_IDLE_H_
+#define _LINUX_IDLE_H_
+
+#include <linux/notifier.h>
+
+enum idle_val {
+	IDLE_START = 1,
+	IDLE_END = 2,
+};
+
+int notify_idle(enum idle_val val);
+void register_idle_notifier(struct notifier_block *n);
+void unregister_idle_notifier(struct notifier_block *n);
+
+#endif /* _LINUX_IDLE_H_ */
diff --git a/kernel/notifier.c b/kernel/notifier.c
index 88453a7e56b..e8481427153 100644
--- a/kernel/notifier.c
+++ b/kernel/notifier.c
@@ -5,6 +5,7 @@
 #include <linux/rcupdate.h>
 #include <linux/vmalloc.h>
 #include <linux/reboot.h>
+#include <linux/idle.h>
 
 /*
  *	Notifier list for kernel code which wants to be called
@@ -584,3 +585,27 @@ int unregister_die_notifier(struct notifier_block *nb)
 	return atomic_notifier_chain_unregister(&die_chain, nb);
 }
 EXPORT_SYMBOL_GPL(unregister_die_notifier);
+
+static ATOMIC_NOTIFIER_HEAD(idle_notifier);
+
+/*
+ * Trace last event before calling notifiers. Notifiers flush data from buffers
+ * before going to idle.
+ */
+int notrace notify_idle(enum idle_val val)
+{
+	return atomic_notifier_call_chain(&idle_notifier, val, NULL);
+}
+EXPORT_SYMBOL_GPL(notify_idle);
+
+void register_idle_notifier(struct notifier_block *n)
+{
+	atomic_notifier_chain_register(&idle_notifier, n);
+}
+EXPORT_SYMBOL_GPL(register_idle_notifier);
+
+void unregister_idle_notifier(struct notifier_block *n)
+{
+	atomic_notifier_chain_unregister(&idle_notifier, n);
+}
+EXPORT_SYMBOL_GPL(unregister_idle_notifier);