Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull CPU hotplug updates from Ingo Molnar:
 "Two changes in this cycle:

   - Make the /sys/devices/system/cpu/smt/* files available on all
     arches, so user space has a consistent way to detect whether SMT is
     enabled.

   - Sparse annotation fix"

* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  smpboot: Place the __percpu annotation correctly
  cpu/hotplug: Create SMT sysfs interface for all arches

1 files changed, 39 insertions, 25 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 1e890f548df8..291757ed10c1 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -2041,19 +2041,6 @@ static const struct attribute_group cpuhp_cpu_root_attr_group = {
 
 #ifdef CONFIG_HOTPLUG_SMT
 
-static const char *smt_states[] = {
-	[CPU_SMT_ENABLED]		= "on",
-	[CPU_SMT_DISABLED]		= "off",
-	[CPU_SMT_FORCE_DISABLED]	= "forceoff",
-	[CPU_SMT_NOT_SUPPORTED]		= "notsupported",
-};
-
-static ssize_t
-show_smt_control(struct device *dev, struct device_attribute *attr, char *buf)
-{
-	return snprintf(buf, PAGE_SIZE - 2, "%s\n", smt_states[cpu_smt_control]);
-}
-
 static void cpuhp_offline_cpu_device(unsigned int cpu)
 {
 	struct device *dev = get_cpu_device(cpu);
@@ -2124,9 +2111,10 @@ static int cpuhp_smt_enable(void)
 	return ret;
 }
 
+
 static ssize_t
-store_smt_control(struct device *dev, struct device_attribute *attr,
-		  const char *buf, size_t count)
+__store_smt_control(struct device *dev, struct device_attribute *attr,
+		    const char *buf, size_t count)
 {
 	int ctrlval, ret;
 
@@ -2164,14 +2152,44 @@ store_smt_control(struct device *dev, struct device_attribute *attr,
 	unlock_device_hotplug();
 	return ret ? ret : count;
 }
+
+#else /* !CONFIG_HOTPLUG_SMT */
+static ssize_t
+__store_smt_control(struct device *dev, struct device_attribute *attr,
+		    const char *buf, size_t count)
+{
+	return -ENODEV;
+}
+#endif /* CONFIG_HOTPLUG_SMT */
+
+static const char *smt_states[] = {
+	[CPU_SMT_ENABLED]		= "on",
+	[CPU_SMT_DISABLED]		= "off",
+	[CPU_SMT_FORCE_DISABLED]	= "forceoff",
+	[CPU_SMT_NOT_SUPPORTED]		= "notsupported",
+	[CPU_SMT_NOT_IMPLEMENTED]	= "notimplemented",
+};
+
+static ssize_t
+show_smt_control(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	const char *state = smt_states[cpu_smt_control];
+
+	return snprintf(buf, PAGE_SIZE - 2, "%s\n", state);
+}
+
+static ssize_t
+store_smt_control(struct device *dev, struct device_attribute *attr,
+		  const char *buf, size_t count)
+{
+	return __store_smt_control(dev, attr, buf, count);
+}
 static DEVICE_ATTR(control, 0644, show_smt_control, store_smt_control);
 
 static ssize_t
 show_smt_active(struct device *dev, struct device_attribute *attr, char *buf)
 {
-	bool active = topology_max_smt_threads() > 1;
-
-	return snprintf(buf, PAGE_SIZE - 2, "%d\n", active);
+	return snprintf(buf, PAGE_SIZE - 2, "%d\n", sched_smt_active());
 }
 static DEVICE_ATTR(active, 0444, show_smt_active, NULL);
 
@@ -2187,21 +2205,17 @@ static const struct attribute_group cpuhp_smt_attr_group = {
 	NULL
 };
 
-static int __init cpu_smt_state_init(void)
+static int __init cpu_smt_sysfs_init(void)
 {
 	return sysfs_create_group(&cpu_subsys.dev_root->kobj,
 				  &cpuhp_smt_attr_group);
 }
 
-#else
-static inline int cpu_smt_state_init(void) { return 0; }
-#endif
-
 static int __init cpuhp_sysfs_init(void)
 {
 	int cpu, ret;
 
-	ret = cpu_smt_state_init();
+	ret = cpu_smt_sysfs_init();
 	if (ret)
 		return ret;
 
@@ -2222,7 +2236,7 @@ static int __init cpuhp_sysfs_init(void)
 	return 0;
 }
 device_initcall(cpuhp_sysfs_init);
-#endif
+#endif /* CONFIG_SYSFS && CONFIG_HOTPLUG_CPU */
 
 /*
  * cpu_bit_bitmap[] is a special, "compressed" data structure that