cpu-hotplug: introduce cpu_notify(), __cpu_notify(), cpu_notify_nofail()

No functional change.  These are just wrappers of
raw_cpu_notifier_call_chain.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 31 insertions, 23 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 124ad9d6be16..09207c772c25 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -134,6 +134,26 @@ int __ref register_cpu_notifier(struct notifier_block *nb)
         return ret;
 }
 
+static int __cpu_notify(unsigned long val, void *v, int nr_to_call,
+                        int *nr_calls)
+{
+        return __raw_notifier_call_chain(&cpu_chain, val, v, nr_to_call,
+                                        nr_calls);
+}
+
+static int cpu_notify(unsigned long val, void *v)
+{
+        return __cpu_notify(val, v, -1, NULL);
+}
+
+static void cpu_notify_nofail(unsigned long val, void *v)
+{
+        int err;
+
+        err = cpu_notify(val, v);
+        BUG_ON(err == NOTIFY_BAD);
+}
+
 #ifdef CONFIG_HOTPLUG_CPU
 
 EXPORT_SYMBOL(register_cpu_notifier);
@@ -181,8 +201,7 @@ static int __ref take_cpu_down(void *_param)
         if (err < 0)
                 return err;
 
-        raw_notifier_call_chain(&cpu_chain, CPU_DYING | param->mod,
-                                param->hcpu);
+        cpu_notify(CPU_DYING | param->mod, param->hcpu);
 
         if (task_cpu(param->caller) == cpu)
                 move_task_off_dead_cpu(cpu, param->caller);
@@ -212,14 +231,12 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
 
         cpu_hotplug_begin();
         set_cpu_active(cpu, false);
-        err = __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_PREPARE | mod,
-                                        hcpu, -1, &nr_calls);
+        err = __cpu_notify(CPU_DOWN_PREPARE | mod, hcpu, -1, &nr_calls);
         if (err == NOTIFY_BAD) {
                 set_cpu_active(cpu, true);
 
                 nr_calls--;
-                __raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
-                                          hcpu, nr_calls, NULL);
+                __cpu_notify(CPU_DOWN_FAILED | mod, hcpu, nr_calls, NULL);
                 printk("%s: attempt to take down CPU %u failed\n",
                                 __func__, cpu);
                 err = -EINVAL;
@@ -230,9 +247,7 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
         if (err) {
                 set_cpu_active(cpu, true);
                 /* CPU didn't die: tell everyone.  Can't complain. */
-                if (raw_notifier_call_chain(&cpu_chain, CPU_DOWN_FAILED | mod,
-                                            hcpu) == NOTIFY_BAD)
-                        BUG();
+                cpu_notify_nofail(CPU_DOWN_FAILED | mod, hcpu);
 
                 goto out_release;
         }
@@ -246,19 +261,14 @@ static int __ref _cpu_down(unsigned int cpu, int tasks_frozen)
         __cpu_die(cpu);
 
         /* CPU is completely dead: tell everyone.  Too late to complain. */
-        if (raw_notifier_call_chain(&cpu_chain, CPU_DEAD | mod,
-                                    hcpu) == NOTIFY_BAD)
-                BUG();
+        cpu_notify_nofail(CPU_DEAD | mod, hcpu);
 
         check_for_tasks(cpu);
 
 out_release:
         cpu_hotplug_done();
-        if (!err) {
-                if (raw_notifier_call_chain(&cpu_chain, CPU_POST_DEAD | mod,
-                                            hcpu) == NOTIFY_BAD)
-                        BUG();
-        }
+        if (!err)
+                cpu_notify_nofail(CPU_POST_DEAD | mod, hcpu);
         return err;
 }
 
@@ -293,8 +303,7 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
                 return -EINVAL;
 
         cpu_hotplug_begin();
-        ret = __raw_notifier_call_chain(&cpu_chain, CPU_UP_PREPARE | mod, hcpu,
-                                                        -1, &nr_calls);
+        ret = __cpu_notify(CPU_UP_PREPARE | mod, hcpu, -1, &nr_calls);
         if (ret == NOTIFY_BAD) {
                 nr_calls--;
                 printk("%s: attempt to bring up CPU %u failed\n",
@@ -312,12 +321,11 @@ static int __cpuinit _cpu_up(unsigned int cpu, int tasks_frozen)
         set_cpu_active(cpu, true);
 
         /* Now call notifier in preparation. */
-        raw_notifier_call_chain(&cpu_chain, CPU_ONLINE | mod, hcpu);
+        cpu_notify(CPU_ONLINE | mod, hcpu);
 
 out_notify:
         if (ret != 0)
-                __raw_notifier_call_chain(&cpu_chain,
-                                CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
+                __cpu_notify(CPU_UP_CANCELED | mod, hcpu, nr_calls, NULL);
         cpu_hotplug_done();
 
         return ret;
@@ -481,7 +489,7 @@ void __cpuinit notify_cpu_starting(unsigned int cpu)
         if (frozen_cpus != NULL && cpumask_test_cpu(cpu, frozen_cpus))
                 val = CPU_STARTING_FROZEN;
 #endif /* CONFIG_PM_SLEEP_SMP */
-        raw_notifier_call_chain(&cpu_chain, val, (void *)(long)cpu);
+        cpu_notify(val, (void *)(long)cpu);
 }
 
 #endif /* CONFIG_SMP */