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authorLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 14:44:49 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-05-06 14:44:49 -0700
commit5a2bf1abbf96fca02b9785c252e569ef8e004851 (patch)
treeba3e9aef86a5868b46a24e8065428a88a72e1bf3 /kernel
parente00d4135751bfe786a9e26b5560b185ce3f9f963 (diff)
parentd4645d30b50d1691c26ff0f8fa4e718b08f8d3bb (diff)
downloadlinux-5a2bf1abbf96fca02b9785c252e569ef8e004851.tar.bz2
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
Diffstat (limited to 'kernel')
-rw-r--r--kernel/cpu.c64
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