1 files changed, 107 insertions, 3 deletions

diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h
index 242bf530edfc..dcfe619171b4 100644
--- a/include/linux/cpuhotplug.h
+++ b/include/linux/cpuhotplug.h
@@ -99,7 +99,7 @@ enum cpuhp_state {
 
 int __cpuhp_setup_state(enum cpuhp_state state, const char *name, bool invoke,
                         int (*startup)(unsigned int cpu),
-                        int (*teardown)(unsigned int cpu));
+                        int (*teardown)(unsigned int cpu), bool multi_instance);
 
 /**
  * cpuhp_setup_state - Setup hotplug state callbacks with calling the callbacks
@@ -116,7 +116,7 @@ static inline int cpuhp_setup_state(enum cpuhp_state state,
                                     int (*startup)(unsigned int cpu),
                                     int (*teardown)(unsigned int cpu))
 {
-        return __cpuhp_setup_state(state, name, true, startup, teardown);
+        return __cpuhp_setup_state(state, name, true, startup, teardown, false);
 }
 
 /**
@@ -135,7 +135,66 @@ static inline int cpuhp_setup_state_nocalls(enum cpuhp_state state,
                                             int (*startup)(unsigned int cpu),
                                             int (*teardown)(unsigned int cpu))
 {
-        return __cpuhp_setup_state(state, name, false, startup, teardown);
+        return __cpuhp_setup_state(state, name, false, startup, teardown,
+                                   false);
+}
+
+/**
+ * cpuhp_setup_state_multi - Add callbacks for multi state
+ * @state:      The state for which the calls are installed
+ * @name:       Name of the callback.
+ * @startup:    startup callback function
+ * @teardown:   teardown callback function
+ *
+ * Sets the internal multi_instance flag and prepares a state to work as a multi
+ * instance callback. No callbacks are invoked at this point. The callbacks are
+ * invoked once an instance for this state are registered via
+ * @cpuhp_state_add_instance or @cpuhp_state_add_instance_nocalls.
+ */
+static inline int cpuhp_setup_state_multi(enum cpuhp_state state,
+                                          const char *name,
+                                          int (*startup)(unsigned int cpu,
+                                                         struct hlist_node *node),
+                                          int (*teardown)(unsigned int cpu,
+                                                          struct hlist_node *node))
+{
+        return __cpuhp_setup_state(state, name, false,
+                                   (void *) startup,
+                                   (void *) teardown, true);
+}
+
+int __cpuhp_state_add_instance(enum cpuhp_state state, struct hlist_node *node,
+                               bool invoke);
+
+/**
+ * cpuhp_state_add_instance - Add an instance for a state and invoke startup
+ *                            callback.
+ * @state:      The state for which the instance is installed
+ * @node:       The node for this individual state.
+ *
+ * Installs the instance for the @state and invokes the startup callback on
+ * the present cpus which have already reached the @state. The @state must have
+ * been earlier marked as multi-instance by @cpuhp_setup_state_multi.
+ */
+static inline int cpuhp_state_add_instance(enum cpuhp_state state,
+                                           struct hlist_node *node)
+{
+        return __cpuhp_state_add_instance(state, node, true);
+}
+
+/**
+ * cpuhp_state_add_instance_nocalls - Add an instance for a state without
+ *                                    invoking the startup callback.
+ * @state:      The state for which the instance is installed
+ * @node:       The node for this individual state.
+ *
+ * Installs the instance for the @state The @state must have been earlier
+ * marked as multi-instance by @cpuhp_setup_state_multi.
+ */
+static inline int cpuhp_state_add_instance_nocalls(enum cpuhp_state state,
+                                                   struct hlist_node *node)
+{
+        return __cpuhp_state_add_instance(state, node, false);
 }
 
 void __cpuhp_remove_state(enum cpuhp_state state, bool invoke);
@@ -162,6 +221,51 @@ static inline void cpuhp_remove_state_nocalls(enum cpuhp_state state)
         __cpuhp_remove_state(state, false);
 }
 
+/**
+ * cpuhp_remove_multi_state - Remove hotplug multi state callback
+ * @state:      The state for which the calls are removed
+ *
+ * Removes the callback functions from a multi state. This is the reverse of
+ * cpuhp_setup_state_multi(). All instances should have been removed before
+ * invoking this function.
+ */
+static inline void cpuhp_remove_multi_state(enum cpuhp_state state)
+{
+        __cpuhp_remove_state(state, false);
+}
+
+int __cpuhp_state_remove_instance(enum cpuhp_state state,
+                                  struct hlist_node *node, bool invoke);
+
+/**
+ * cpuhp_state_remove_instance - Remove hotplug instance from state and invoke
+ *                               the teardown callback
+ * @state:      The state from which the instance is removed
+ * @node:       The node for this individual state.
+ *
+ * Removes the instance and invokes the teardown callback on the present cpus
+ * which have already reached the @state.
+ */
+static inline int cpuhp_state_remove_instance(enum cpuhp_state state,
+                                              struct hlist_node *node)
+{
+        return __cpuhp_state_remove_instance(state, node, true);
+}
+
+/**
+ * cpuhp_state_remove_instance_nocalls - Remove hotplug instance from state
+ *                                       without invoking the reatdown callback
+ * @state:      The state from which the instance is removed
+ * @node:       The node for this individual state.
+ *
+ * Removes the instance without invoking the teardown callback.
+ */
+static inline int cpuhp_state_remove_instance_nocalls(enum cpuhp_state state,
+                                                      struct hlist_node *node)
+{
+        return __cpuhp_state_remove_instance(state, node, false);
+}
+
 #ifdef CONFIG_SMP
 void cpuhp_online_idle(enum cpuhp_state state);
 #else