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authorRafael J. Wysocki <rafael.j.wysocki@intel.com>2013-06-28 12:58:05 +0200
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>2013-06-28 12:58:05 +0200
commita204dbc61b7f4cb1a7e2cb3ad057b135164782da (patch)
treef82151c04a30f49c3dee8926d184575ad2e7b1e2 /drivers/base
parent45e00374db944b1c12987b501bcaa279b3e36d93 (diff)
parent08f502c1c343031f0d126bd00e87dede38269d12 (diff)
Merge branch 'acpi-hotplug'
* acpi-hotplug: ACPI: Do not use CONFIG_ACPI_HOTPLUG_MEMORY_MODULE ACPI / cpufreq: Add ACPI processor device IDs to acpi-cpufreq Memory hotplug: Move alternative function definitions to header ACPI / processor: Fix potential NULL pointer dereference in acpi_processor_add() Memory hotplug / ACPI: Simplify memory removal ACPI / scan: Add second pass of companion offlining to hot-remove code Driver core / MM: Drop offline_memory_block() ACPI / processor: Pass processor object handle to acpi_bind_one() ACPI: Drop removal_type field from struct acpi_device Driver core / memory: Simplify __memory_block_change_state() ACPI / processor: Initialize per_cpu(processors, pr->id) properly CPU: Fix sysfs cpu/online of offlined CPUs Driver core: Introduce offline/online callbacks for memory blocks ACPI / memhotplug: Bind removable memory blocks to ACPI device nodes ACPI / processor: Use common hotplug infrastructure ACPI / hotplug: Use device offline/online for graceful hot-removal Driver core: Use generic offline/online for CPU offline/online Driver core: Add offline/online device operations
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/core.c130
-rw-r--r--drivers/base/cpu.c101
-rw-r--r--drivers/base/memory.c114
3 files changed, 248 insertions, 97 deletions
diff --git a/drivers/base/core.c b/drivers/base/core.c
index 2499cefdcdf2..2166f34b7d84 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -403,6 +403,36 @@ static ssize_t store_uevent(struct device *dev, struct device_attribute *attr,
static struct device_attribute uevent_attr =
__ATTR(uevent, S_IRUGO | S_IWUSR, show_uevent, store_uevent);
+static ssize_t show_online(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ bool val;
+
+ lock_device_hotplug();
+ val = !dev->offline;
+ unlock_device_hotplug();
+ return sprintf(buf, "%u\n", val);
+}
+
+static ssize_t store_online(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ bool val;
+ int ret;
+
+ ret = strtobool(buf, &val);
+ if (ret < 0)
+ return ret;
+
+ lock_device_hotplug();
+ ret = val ? device_online(dev) : device_offline(dev);
+ unlock_device_hotplug();
+ return ret < 0 ? ret : count;
+}
+
+static struct device_attribute online_attr =
+ __ATTR(online, S_IRUGO | S_IWUSR, show_online, store_online);
+
static int device_add_attributes(struct device *dev,
struct device_attribute *attrs)
{
@@ -516,6 +546,12 @@ static int device_add_attrs(struct device *dev)
if (error)
goto err_remove_type_groups;
+ if (device_supports_offline(dev) && !dev->offline_disabled) {
+ error = device_create_file(dev, &online_attr);
+ if (error)
+ goto err_remove_type_groups;
+ }
+
return 0;
err_remove_type_groups:
@@ -536,6 +572,7 @@ static void device_remove_attrs(struct device *dev)
struct class *class = dev->class;
const struct device_type *type = dev->type;
+ device_remove_file(dev, &online_attr);
device_remove_groups(dev, dev->groups);
if (type)
@@ -1433,6 +1470,99 @@ EXPORT_SYMBOL_GPL(put_device);
EXPORT_SYMBOL_GPL(device_create_file);
EXPORT_SYMBOL_GPL(device_remove_file);
+static DEFINE_MUTEX(device_hotplug_lock);
+
+void lock_device_hotplug(void)
+{
+ mutex_lock(&device_hotplug_lock);
+}
+
+void unlock_device_hotplug(void)
+{
+ mutex_unlock(&device_hotplug_lock);
+}
+
+static int device_check_offline(struct device *dev, void *not_used)
+{
+ int ret;
+
+ ret = device_for_each_child(dev, NULL, device_check_offline);
+ if (ret)
+ return ret;
+
+ return device_supports_offline(dev) && !dev->offline ? -EBUSY : 0;
+}
+
+/**
+ * device_offline - Prepare the device for hot-removal.
+ * @dev: Device to be put offline.
+ *
+ * Execute the device bus type's .offline() callback, if present, to prepare
+ * the device for a subsequent hot-removal. If that succeeds, the device must
+ * not be used until either it is removed or its bus type's .online() callback
+ * is executed.
+ *
+ * Call under device_hotplug_lock.
+ */
+int device_offline(struct device *dev)
+{
+ int ret;
+
+ if (dev->offline_disabled)
+ return -EPERM;
+
+ ret = device_for_each_child(dev, NULL, device_check_offline);
+ if (ret)
+ return ret;
+
+ device_lock(dev);
+ if (device_supports_offline(dev)) {
+ if (dev->offline) {
+ ret = 1;
+ } else {
+ ret = dev->bus->offline(dev);
+ if (!ret) {
+ kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
+ dev->offline = true;
+ }
+ }
+ }
+ device_unlock(dev);
+
+ return ret;
+}
+
+/**
+ * device_online - Put the device back online after successful device_offline().
+ * @dev: Device to be put back online.
+ *
+ * If device_offline() has been successfully executed for @dev, but the device
+ * has not been removed subsequently, execute its bus type's .online() callback
+ * to indicate that the device can be used again.
+ *
+ * Call under device_hotplug_lock.
+ */
+int device_online(struct device *dev)
+{
+ int ret = 0;
+
+ device_lock(dev);
+ if (device_supports_offline(dev)) {
+ if (dev->offline) {
+ ret = dev->bus->online(dev);
+ if (!ret) {
+ kobject_uevent(&dev->kobj, KOBJ_ONLINE);
+ dev->offline = false;
+ }
+ } else {
+ ret = 1;
+ }
+ }
+ device_unlock(dev);
+
+ return ret;
+}
+
struct root_device {
struct device dev;
struct module *owner;
diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index 3d48fc887ef4..1d110dc6f0c1 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -13,17 +13,21 @@
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/percpu.h>
+#include <linux/acpi.h>
#include "base.h"
-struct bus_type cpu_subsys = {
- .name = "cpu",
- .dev_name = "cpu",
-};
-EXPORT_SYMBOL_GPL(cpu_subsys);
-
static DEFINE_PER_CPU(struct device *, cpu_sys_devices);
+static int cpu_subsys_match(struct device *dev, struct device_driver *drv)
+{
+ /* ACPI style match is the only one that may succeed. */
+ if (acpi_driver_match_device(dev, drv))
+ return 1;
+
+ return 0;
+}
+
#ifdef CONFIG_HOTPLUG_CPU
static void change_cpu_under_node(struct cpu *cpu,
unsigned int from_nid, unsigned int to_nid)
@@ -34,69 +38,45 @@ static void change_cpu_under_node(struct cpu *cpu,
cpu->node_id = to_nid;
}
-static ssize_t show_online(struct device *dev,
- struct device_attribute *attr,
- char *buf)
+static int __ref cpu_subsys_online(struct device *dev)
{
struct cpu *cpu = container_of(dev, struct cpu, dev);
+ int cpuid = dev->id;
+ int from_nid, to_nid;
+ int ret;
- return sprintf(buf, "%u\n", !!cpu_online(cpu->dev.id));
+ cpu_hotplug_driver_lock();
+
+ from_nid = cpu_to_node(cpuid);
+ ret = cpu_up(cpuid);
+ /*
+ * When hot adding memory to memoryless node and enabling a cpu
+ * on the node, node number of the cpu may internally change.
+ */
+ to_nid = cpu_to_node(cpuid);
+ if (from_nid != to_nid)
+ change_cpu_under_node(cpu, from_nid, to_nid);
+
+ cpu_hotplug_driver_unlock();
+ return ret;
}
-static ssize_t __ref store_online(struct device *dev,
- struct device_attribute *attr,
- const char *buf, size_t count)
+static int cpu_subsys_offline(struct device *dev)
{
- struct cpu *cpu = container_of(dev, struct cpu, dev);
- int cpuid = cpu->dev.id;
- int from_nid, to_nid;
- ssize_t ret;
+ int ret;
cpu_hotplug_driver_lock();
- switch (buf[0]) {
- case '0':
- ret = cpu_down(cpuid);
- if (!ret)
- kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
- break;
- case '1':
- from_nid = cpu_to_node(cpuid);
- ret = cpu_up(cpuid);
-
- /*
- * When hot adding memory to memoryless node and enabling a cpu
- * on the node, node number of the cpu may internally change.
- */
- to_nid = cpu_to_node(cpuid);
- if (from_nid != to_nid)
- change_cpu_under_node(cpu, from_nid, to_nid);
-
- if (!ret)
- kobject_uevent(&dev->kobj, KOBJ_ONLINE);
- break;
- default:
- ret = -EINVAL;
- }
+ ret = cpu_down(dev->id);
cpu_hotplug_driver_unlock();
-
- if (ret >= 0)
- ret = count;
return ret;
}
-static DEVICE_ATTR(online, 0644, show_online, store_online);
-static void __cpuinit register_cpu_control(struct cpu *cpu)
-{
- device_create_file(&cpu->dev, &dev_attr_online);
-}
void unregister_cpu(struct cpu *cpu)
{
int logical_cpu = cpu->dev.id;
unregister_cpu_under_node(logical_cpu, cpu_to_node(logical_cpu));
- device_remove_file(&cpu->dev, &dev_attr_online);
-
device_unregister(&cpu->dev);
per_cpu(cpu_sys_devices, logical_cpu) = NULL;
return;
@@ -123,12 +103,19 @@ static DEVICE_ATTR(probe, S_IWUSR, NULL, cpu_probe_store);
static DEVICE_ATTR(release, S_IWUSR, NULL, cpu_release_store);
#endif /* CONFIG_ARCH_CPU_PROBE_RELEASE */
-#else /* ... !CONFIG_HOTPLUG_CPU */
-static inline void register_cpu_control(struct cpu *cpu)
-{
-}
#endif /* CONFIG_HOTPLUG_CPU */
+struct bus_type cpu_subsys = {
+ .name = "cpu",
+ .dev_name = "cpu",
+ .match = cpu_subsys_match,
+#ifdef CONFIG_HOTPLUG_CPU
+ .online = cpu_subsys_online,
+ .offline = cpu_subsys_offline,
+#endif
+};
+EXPORT_SYMBOL_GPL(cpu_subsys);
+
#ifdef CONFIG_KEXEC
#include <linux/kexec.h>
@@ -277,12 +264,12 @@ int __cpuinit register_cpu(struct cpu *cpu, int num)
cpu->dev.id = num;
cpu->dev.bus = &cpu_subsys;
cpu->dev.release = cpu_device_release;
+ cpu->dev.offline_disabled = !cpu->hotpluggable;
+ cpu->dev.offline = !cpu_online(num);
#ifdef CONFIG_ARCH_HAS_CPU_AUTOPROBE
cpu->dev.bus->uevent = arch_cpu_uevent;
#endif
error = device_register(&cpu->dev);
- if (!error && cpu->hotpluggable)
- register_cpu_control(cpu);
if (!error)
per_cpu(cpu_sys_devices, num) = &cpu->dev;
if (!error)
diff --git a/drivers/base/memory.c b/drivers/base/memory.c
index 14f8a6954da0..4ebf97f99fae 100644
--- a/drivers/base/memory.c
+++ b/drivers/base/memory.c
@@ -37,9 +37,14 @@ static inline int base_memory_block_id(int section_nr)
return section_nr / sections_per_block;
}
+static int memory_subsys_online(struct device *dev);
+static int memory_subsys_offline(struct device *dev);
+
static struct bus_type memory_subsys = {
.name = MEMORY_CLASS_NAME,
.dev_name = MEMORY_CLASS_NAME,
+ .online = memory_subsys_online,
+ .offline = memory_subsys_offline,
};
static BLOCKING_NOTIFIER_HEAD(memory_chain);
@@ -88,6 +93,7 @@ int register_memory(struct memory_block *memory)
memory->dev.bus = &memory_subsys;
memory->dev.id = memory->start_section_nr / sections_per_block;
memory->dev.release = memory_block_release;
+ memory->dev.offline = memory->state == MEM_OFFLINE;
error = device_register(&memory->dev);
return error;
@@ -278,33 +284,64 @@ static int __memory_block_change_state(struct memory_block *mem,
{
int ret = 0;
- if (mem->state != from_state_req) {
- ret = -EINVAL;
- goto out;
- }
+ if (mem->state != from_state_req)
+ return -EINVAL;
if (to_state == MEM_OFFLINE)
mem->state = MEM_GOING_OFFLINE;
ret = memory_block_action(mem->start_section_nr, to_state, online_type);
+ mem->state = ret ? from_state_req : to_state;
+ return ret;
+}
- if (ret) {
- mem->state = from_state_req;
- goto out;
- }
+static int memory_subsys_online(struct device *dev)
+{
+ struct memory_block *mem = container_of(dev, struct memory_block, dev);
+ int ret;
- mem->state = to_state;
- switch (mem->state) {
- case MEM_OFFLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
- break;
- case MEM_ONLINE:
- kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
- break;
- default:
- break;
+ mutex_lock(&mem->state_mutex);
+
+ ret = mem->state == MEM_ONLINE ? 0 :
+ __memory_block_change_state(mem, MEM_ONLINE, MEM_OFFLINE,
+ ONLINE_KEEP);
+
+ mutex_unlock(&mem->state_mutex);
+ return ret;
+}
+
+static int memory_subsys_offline(struct device *dev)
+{
+ struct memory_block *mem = container_of(dev, struct memory_block, dev);
+ int ret;
+
+ mutex_lock(&mem->state_mutex);
+
+ ret = mem->state == MEM_OFFLINE ? 0 :
+ __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
+
+ mutex_unlock(&mem->state_mutex);
+ return ret;
+}
+
+static int __memory_block_change_state_uevent(struct memory_block *mem,
+ unsigned long to_state, unsigned long from_state_req,
+ int online_type)
+{
+ int ret = __memory_block_change_state(mem, to_state, from_state_req,
+ online_type);
+ if (!ret) {
+ switch (mem->state) {
+ case MEM_OFFLINE:
+ kobject_uevent(&mem->dev.kobj, KOBJ_OFFLINE);
+ break;
+ case MEM_ONLINE:
+ kobject_uevent(&mem->dev.kobj, KOBJ_ONLINE);
+ break;
+ default:
+ break;
+ }
}
-out:
return ret;
}
@@ -315,8 +352,8 @@ static int memory_block_change_state(struct memory_block *mem,
int ret;
mutex_lock(&mem->state_mutex);
- ret = __memory_block_change_state(mem, to_state, from_state_req,
- online_type);
+ ret = __memory_block_change_state_uevent(mem, to_state, from_state_req,
+ online_type);
mutex_unlock(&mem->state_mutex);
return ret;
@@ -326,22 +363,34 @@ store_mem_state(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct memory_block *mem;
+ bool offline;
int ret = -EINVAL;
mem = container_of(dev, struct memory_block, dev);
- if (!strncmp(buf, "online_kernel", min_t(int, count, 13)))
+ lock_device_hotplug();
+
+ if (!strncmp(buf, "online_kernel", min_t(int, count, 13))) {
+ offline = false;
ret = memory_block_change_state(mem, MEM_ONLINE,
MEM_OFFLINE, ONLINE_KERNEL);
- else if (!strncmp(buf, "online_movable", min_t(int, count, 14)))
+ } else if (!strncmp(buf, "online_movable", min_t(int, count, 14))) {
+ offline = false;
ret = memory_block_change_state(mem, MEM_ONLINE,
MEM_OFFLINE, ONLINE_MOVABLE);
- else if (!strncmp(buf, "online", min_t(int, count, 6)))
+ } else if (!strncmp(buf, "online", min_t(int, count, 6))) {
+ offline = false;
ret = memory_block_change_state(mem, MEM_ONLINE,
MEM_OFFLINE, ONLINE_KEEP);
- else if(!strncmp(buf, "offline", min_t(int, count, 7)))
+ } else if(!strncmp(buf, "offline", min_t(int, count, 7))) {
+ offline = true;
ret = memory_block_change_state(mem, MEM_OFFLINE,
MEM_ONLINE, -1);
+ }
+ if (!ret)
+ dev->offline = offline;
+
+ unlock_device_hotplug();
if (ret)
return ret;
@@ -679,21 +728,6 @@ int unregister_memory_section(struct mem_section *section)
}
#endif /* CONFIG_MEMORY_HOTREMOVE */
-/*
- * offline one memory block. If the memory block has been offlined, do nothing.
- */
-int offline_memory_block(struct memory_block *mem)
-{
- int ret = 0;
-
- mutex_lock(&mem->state_mutex);
- if (mem->state != MEM_OFFLINE)
- ret = __memory_block_change_state(mem, MEM_OFFLINE, MEM_ONLINE, -1);
- mutex_unlock(&mem->state_mutex);
-
- return ret;
-}
-
/* return true if the memory block is offlined, otherwise, return false */
bool is_memblock_offlined(struct memory_block *mem)
{