1 files changed, 93 insertions, 0 deletions
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
new file mode 100644
index 000000000000..5d68e15e46b7
--- /dev/null
+++ b/include/linux/cpuhotplug.h
@@ -0,0 +1,93 @@
+#ifndef __CPUHOTPLUG_H
+#define __CPUHOTPLUG_H
+
+enum cpuhp_state {
+	CPUHP_OFFLINE,
+	CPUHP_CREATE_THREADS,
+	CPUHP_NOTIFY_PREPARE,
+	CPUHP_BRINGUP_CPU,
+	CPUHP_AP_IDLE_DEAD,
+	CPUHP_AP_OFFLINE,
+	CPUHP_AP_NOTIFY_STARTING,
+	CPUHP_AP_ONLINE,
+	CPUHP_TEARDOWN_CPU,
+	CPUHP_AP_ONLINE_IDLE,
+	CPUHP_AP_SMPBOOT_THREADS,
+	CPUHP_AP_NOTIFY_ONLINE,
+	CPUHP_AP_ONLINE_DYN,
+	CPUHP_AP_ONLINE_DYN_END		= CPUHP_AP_ONLINE_DYN + 30,
+	CPUHP_ONLINE,
+};
+
+int __cpuhp_setup_state(enum cpuhp_state state,	const char *name, bool invoke,
+			int (*startup)(unsigned int cpu),
+			int (*teardown)(unsigned int cpu));
+
+/**
+ * cpuhp_setup_state - Setup hotplug state callbacks with calling the callbacks
+ * @state:	The state for which the calls are installed
+ * @name:	Name of the callback (will be used in debug output)
+ * @startup:	startup callback function
+ * @teardown:	teardown callback function
+ *
+ * Installs the callback functions and invokes the startup callback on
+ * the present cpus which have already reached the @state.
+ */
+static inline int cpuhp_setup_state(enum cpuhp_state state,
+				    const char *name,
+				    int (*startup)(unsigned int cpu),
+				    int (*teardown)(unsigned int cpu))
+{
+	return __cpuhp_setup_state(state, name, true, startup, teardown);
+}
+
+/**
+ * cpuhp_setup_state_nocalls - Setup hotplug state callbacks without calling the
+ *			       callbacks
+ * @state:	The state for which the calls are installed
+ * @name:	Name of the callback.
+ * @startup:	startup callback function
+ * @teardown:	teardown callback function
+ *
+ * Same as @cpuhp_setup_state except that no calls are executed are invoked
+ * during installation of this callback. NOP if SMP=n or HOTPLUG_CPU=n.
+ */
+static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
+					    const char *name,
+					    int (*startup)(unsigned int cpu),
+					    int (*teardown)(unsigned int cpu))
+{
+	return __cpuhp_setup_state(state, name, false, startup, teardown);
+}
+
+void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
+
+/**
+ * cpuhp_remove_state - Remove hotplug state callbacks and invoke the teardown
+ * @state:	The state for which the calls are removed
+ *
+ * Removes the callback functions and invokes the teardown callback on
+ * the present cpus which have already reached the @state.
+ */
+static inline void cpuhp_remove_state(enum cpuhp_state state)
+{
+	__cpuhp_remove_state(state, true);
+}
+
+/**
+ * cpuhp_remove_state_nocalls - Remove hotplug state callbacks without invoking
+ *				teardown
+ * @state:	The state for which the calls are removed
+ */
+static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
+{
+	__cpuhp_remove_state(state, false);
+}
+
+#ifdef CONFIG_SMP
+void cpuhp_online_idle(enum cpuhp_state state);
+#else
+static inline void cpuhp_online_idle(enum cpuhp_state state) { }
+#endif
+
+#endif