cpu/hotplug: Merge cpuhp_bp_states and cpuhp_ap_states

cpuhp_bp_states and cpuhp_ap_states have different set of steps without any
conflicting steps, so that they can be merged.

The original `[CPUHP_BRINGUP_CPU] = { },` is removed, because the new
cpuhp_hp_states has CPUHP_ONLINE index which is larger than
CPUHP_BRINGUP_CPU.

Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Link: https://lkml.kernel.org/r/20171201135008.21633-1-jiangshanlai@gmail.com

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 53f7dc6..a1860d4 100644 (file)
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -124,8 +124,7 @@ struct cpuhp_step {
 };
 
 static DEFINE_MUTEX(cpuhp_state_mutex);
-static struct cpuhp_step cpuhp_bp_states[];
-static struct cpuhp_step cpuhp_ap_states[];
+static struct cpuhp_step cpuhp_hp_states[];
 
 static bool cpuhp_is_ap_state(enum cpuhp_state state)
 {
@@ -138,10 +137,7 @@ static bool cpuhp_is_ap_state(enum cpuhp_state state)
 
 static struct cpuhp_step *cpuhp_get_step(enum cpuhp_state state)
 {
-       struct cpuhp_step *sp;
-
-       sp = cpuhp_is_ap_state(state) ? cpuhp_ap_states : cpuhp_bp_states;
-       return sp + state;
+       return cpuhp_hp_states + state;
 }
 
 /**
@@ -1224,7 +1220,7 @@ int __boot_cpu_id;
 #endif /* CONFIG_SMP */
 
 /* Boot processor state steps */
-static struct cpuhp_step cpuhp_bp_states[] = {
+static struct cpuhp_step cpuhp_hp_states[] = {
        [CPUHP_OFFLINE] = {
                .name                   = "offline",
                .startup.single         = NULL,
@@ -1289,24 +1285,6 @@ static struct cpuhp_step cpuhp_bp_states[] = {
                .teardown.single        = NULL,
                .cant_stop              = true,
        },
-       /*
-        * Handled on controll processor until the plugged processor manages
-        * this itself.
-        */
-       [CPUHP_TEARDOWN_CPU] = {
-               .name                   = "cpu:teardown",
-               .startup.single         = NULL,
-               .teardown.single        = takedown_cpu,
-               .cant_stop              = true,
-       },
-#else
-       [CPUHP_BRINGUP_CPU] = { },
-#endif
-};
-
-/* Application processor state steps */
-static struct cpuhp_step cpuhp_ap_states[] = {
-#ifdef CONFIG_SMP
        /* Final state before CPU kills itself */
        [CPUHP_AP_IDLE_DEAD] = {
                .name                   = "idle:dead",
@@ -1340,6 +1318,16 @@ static struct cpuhp_step cpuhp_ap_states[] = {
        [CPUHP_AP_ONLINE] = {
                .name                   = "ap:online",
        },
+       /*
+        * Handled on controll processor until the plugged processor manages
+        * this itself.
+        */
+       [CPUHP_TEARDOWN_CPU] = {
+               .name                   = "cpu:teardown",
+               .startup.single         = NULL,
+               .teardown.single        = takedown_cpu,
+               .cant_stop              = true,
+       },
        /* Handle smpboot threads park/unpark */
        [CPUHP_AP_SMPBOOT_THREADS] = {
                .name                   = "smpboot/threads:online",
@@ -1408,11 +1396,11 @@ static int cpuhp_reserve_state(enum cpuhp_state state)
 
        switch (state) {
        case CPUHP_AP_ONLINE_DYN:
-               step = cpuhp_ap_states + CPUHP_AP_ONLINE_DYN;
+               step = cpuhp_hp_states + CPUHP_AP_ONLINE_DYN;
                end = CPUHP_AP_ONLINE_DYN_END;
                break;
        case CPUHP_BP_PREPARE_DYN:
-               step = cpuhp_bp_states + CPUHP_BP_PREPARE_DYN;
+               step = cpuhp_hp_states + CPUHP_BP_PREPARE_DYN;
                end = CPUHP_BP_PREPARE_DYN_END;
                break;
        default: