linux/drivers/base/node.c

1024 lines
27 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Basic Node interface support
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/mm.h>
#include <linux/memory.h>
#include <linux/vmstat.h>
#include <linux/notifier.h>
#include <linux/node.h>
#include <linux/hugetlb.h>
#include <linux/compaction.h>
#include <linux/cpumask.h>
#include <linux/topology.h>
#include <linux/nodemask.h>
#include <linux/cpu.h>
#include <linux/device.h>
#include <linux/pm_runtime.h>
#include <linux/swap.h>
#include <linux/slab.h>
static struct bus_type node_subsys = {
.name = "node",
.dev_name = "node",
};
static ssize_t node_read_cpumap(struct device *dev, bool list, char *buf)
{
ssize_t n;
cpumask_var_t mask;
struct node *node_dev = to_node(dev);
/* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
if (!alloc_cpumask_var(&mask, GFP_KERNEL))
return 0;
cpumask_and(mask, cpumask_of_node(node_dev->dev.id), cpu_online_mask);
n = cpumap_print_to_pagebuf(list, buf, mask);
free_cpumask_var(mask);
return n;
}
static inline ssize_t node_read_cpumask(struct device *dev,
struct device_attribute *attr, char *buf)
{
return node_read_cpumap(dev, false, buf);
}
static inline ssize_t node_read_cpulist(struct device *dev,
struct device_attribute *attr, char *buf)
{
return node_read_cpumap(dev, true, buf);
}
static DEVICE_ATTR(cpumap, S_IRUGO, node_read_cpumask, NULL);
static DEVICE_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
/**
* struct node_access_nodes - Access class device to hold user visible
* relationships to other nodes.
* @dev: Device for this memory access class
* @list_node: List element in the node's access list
* @access: The access class rank
* @hmem_attrs: Heterogeneous memory performance attributes
*/
struct node_access_nodes {
struct device dev;
struct list_head list_node;
unsigned access;
#ifdef CONFIG_HMEM_REPORTING
struct node_hmem_attrs hmem_attrs;
#endif
};
#define to_access_nodes(dev) container_of(dev, struct node_access_nodes, dev)
static struct attribute *node_init_access_node_attrs[] = {
NULL,
};
static struct attribute *node_targ_access_node_attrs[] = {
NULL,
};
static const struct attribute_group initiators = {
.name = "initiators",
.attrs = node_init_access_node_attrs,
};
static const struct attribute_group targets = {
.name = "targets",
.attrs = node_targ_access_node_attrs,
};
static const struct attribute_group *node_access_node_groups[] = {
&initiators,
&targets,
NULL,
};
static void node_remove_accesses(struct node *node)
{
struct node_access_nodes *c, *cnext;
list_for_each_entry_safe(c, cnext, &node->access_list, list_node) {
list_del(&c->list_node);
device_unregister(&c->dev);
}
}
static void node_access_release(struct device *dev)
{
kfree(to_access_nodes(dev));
}
static struct node_access_nodes *node_init_node_access(struct node *node,
unsigned access)
{
struct node_access_nodes *access_node;
struct device *dev;
list_for_each_entry(access_node, &node->access_list, list_node)
if (access_node->access == access)
return access_node;
access_node = kzalloc(sizeof(*access_node), GFP_KERNEL);
if (!access_node)
return NULL;
access_node->access = access;
dev = &access_node->dev;
dev->parent = &node->dev;
dev->release = node_access_release;
dev->groups = node_access_node_groups;
if (dev_set_name(dev, "access%u", access))
goto free;
if (device_register(dev))
goto free_name;
pm_runtime_no_callbacks(dev);
list_add_tail(&access_node->list_node, &node->access_list);
return access_node;
free_name:
kfree_const(dev->kobj.name);
free:
kfree(access_node);
return NULL;
}
#ifdef CONFIG_HMEM_REPORTING
#define ACCESS_ATTR(name) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
return sprintf(buf, "%u\n", to_access_nodes(dev)->hmem_attrs.name); \
} \
static DEVICE_ATTR_RO(name);
ACCESS_ATTR(read_bandwidth)
ACCESS_ATTR(read_latency)
ACCESS_ATTR(write_bandwidth)
ACCESS_ATTR(write_latency)
static struct attribute *access_attrs[] = {
&dev_attr_read_bandwidth.attr,
&dev_attr_read_latency.attr,
&dev_attr_write_bandwidth.attr,
&dev_attr_write_latency.attr,
NULL,
};
/**
* node_set_perf_attrs - Set the performance values for given access class
* @nid: Node identifier to be set
* @hmem_attrs: Heterogeneous memory performance attributes
* @access: The access class the for the given attributes
*/
void node_set_perf_attrs(unsigned int nid, struct node_hmem_attrs *hmem_attrs,
unsigned access)
{
struct node_access_nodes *c;
struct node *node;
int i;
if (WARN_ON_ONCE(!node_online(nid)))
return;
node = node_devices[nid];
c = node_init_node_access(node, access);
if (!c)
return;
c->hmem_attrs = *hmem_attrs;
for (i = 0; access_attrs[i] != NULL; i++) {
if (sysfs_add_file_to_group(&c->dev.kobj, access_attrs[i],
"initiators")) {
pr_info("failed to add performance attribute to node %d\n",
nid);
break;
}
}
}
/**
* struct node_cache_info - Internal tracking for memory node caches
* @dev: Device represeting the cache level
* @node: List element for tracking in the node
* @cache_attrs:Attributes for this cache level
*/
struct node_cache_info {
struct device dev;
struct list_head node;
struct node_cache_attrs cache_attrs;
};
#define to_cache_info(device) container_of(device, struct node_cache_info, dev)
#define CACHE_ATTR(name, fmt) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, \
char *buf) \
{ \
return sprintf(buf, fmt "\n", to_cache_info(dev)->cache_attrs.name);\
} \
DEVICE_ATTR_RO(name);
CACHE_ATTR(size, "%llu")
CACHE_ATTR(line_size, "%u")
CACHE_ATTR(indexing, "%u")
CACHE_ATTR(write_policy, "%u")
static struct attribute *cache_attrs[] = {
&dev_attr_indexing.attr,
&dev_attr_size.attr,
&dev_attr_line_size.attr,
&dev_attr_write_policy.attr,
NULL,
};
ATTRIBUTE_GROUPS(cache);
static void node_cache_release(struct device *dev)
{
kfree(dev);
}
static void node_cacheinfo_release(struct device *dev)
{
struct node_cache_info *info = to_cache_info(dev);
kfree(info);
}
static void node_init_cache_dev(struct node *node)
{
struct device *dev;
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return;
dev->parent = &node->dev;
dev->release = node_cache_release;
if (dev_set_name(dev, "memory_side_cache"))
goto free_dev;
if (device_register(dev))
goto free_name;
pm_runtime_no_callbacks(dev);
node->cache_dev = dev;
return;
free_name:
kfree_const(dev->kobj.name);
free_dev:
kfree(dev);
}
/**
* node_add_cache() - add cache attribute to a memory node
* @nid: Node identifier that has new cache attributes
* @cache_attrs: Attributes for the cache being added
*/
void node_add_cache(unsigned int nid, struct node_cache_attrs *cache_attrs)
{
struct node_cache_info *info;
struct device *dev;
struct node *node;
if (!node_online(nid) || !node_devices[nid])
return;
node = node_devices[nid];
list_for_each_entry(info, &node->cache_attrs, node) {
if (info->cache_attrs.level == cache_attrs->level) {
dev_warn(&node->dev,
"attempt to add duplicate cache level:%d\n",
cache_attrs->level);
return;
}
}
if (!node->cache_dev)
node_init_cache_dev(node);
if (!node->cache_dev)
return;
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
return;
dev = &info->dev;
dev->parent = node->cache_dev;
dev->release = node_cacheinfo_release;
dev->groups = cache_groups;
if (dev_set_name(dev, "index%d", cache_attrs->level))
goto free_cache;
info->cache_attrs = *cache_attrs;
if (device_register(dev)) {
dev_warn(&node->dev, "failed to add cache level:%d\n",
cache_attrs->level);
goto free_name;
}
pm_runtime_no_callbacks(dev);
list_add_tail(&info->node, &node->cache_attrs);
return;
free_name:
kfree_const(dev->kobj.name);
free_cache:
kfree(info);
}
static void node_remove_caches(struct node *node)
{
struct node_cache_info *info, *next;
if (!node->cache_dev)
return;
list_for_each_entry_safe(info, next, &node->cache_attrs, node) {
list_del(&info->node);
device_unregister(&info->dev);
}
device_unregister(node->cache_dev);
}
static void node_init_caches(unsigned int nid)
{
INIT_LIST_HEAD(&node_devices[nid]->cache_attrs);
}
#else
static void node_init_caches(unsigned int nid) { }
static void node_remove_caches(struct node *node) { }
#endif
#define K(x) ((x) << (PAGE_SHIFT - 10))
static ssize_t node_read_meminfo(struct device *dev,
struct device_attribute *attr, char *buf)
{
int n;
int nid = dev->id;
struct pglist_data *pgdat = NODE_DATA(nid);
struct sysinfo i;
unsigned long sreclaimable, sunreclaimable;
si_meminfo_node(&i, nid);
sreclaimable = node_page_state(pgdat, NR_SLAB_RECLAIMABLE);
sunreclaimable = node_page_state(pgdat, NR_SLAB_UNRECLAIMABLE);
n = sprintf(buf,
"Node %d MemTotal: %8lu kB\n"
"Node %d MemFree: %8lu kB\n"
"Node %d MemUsed: %8lu kB\n"
"Node %d Active: %8lu kB\n"
"Node %d Inactive: %8lu kB\n"
"Node %d Active(anon): %8lu kB\n"
"Node %d Inactive(anon): %8lu kB\n"
"Node %d Active(file): %8lu kB\n"
"Node %d Inactive(file): %8lu kB\n"
"Node %d Unevictable: %8lu kB\n"
"Node %d Mlocked: %8lu kB\n",
nid, K(i.totalram),
nid, K(i.freeram),
nid, K(i.totalram - i.freeram),
nid, K(node_page_state(pgdat, NR_ACTIVE_ANON) +
node_page_state(pgdat, NR_ACTIVE_FILE)),
nid, K(node_page_state(pgdat, NR_INACTIVE_ANON) +
node_page_state(pgdat, NR_INACTIVE_FILE)),
nid, K(node_page_state(pgdat, NR_ACTIVE_ANON)),
nid, K(node_page_state(pgdat, NR_INACTIVE_ANON)),
nid, K(node_page_state(pgdat, NR_ACTIVE_FILE)),
nid, K(node_page_state(pgdat, NR_INACTIVE_FILE)),
nid, K(node_page_state(pgdat, NR_UNEVICTABLE)),
nid, K(sum_zone_node_page_state(nid, NR_MLOCK)));
#ifdef CONFIG_HIGHMEM
n += sprintf(buf + n,
"Node %d HighTotal: %8lu kB\n"
"Node %d HighFree: %8lu kB\n"
"Node %d LowTotal: %8lu kB\n"
"Node %d LowFree: %8lu kB\n",
nid, K(i.totalhigh),
nid, K(i.freehigh),
nid, K(i.totalram - i.totalhigh),
nid, K(i.freeram - i.freehigh));
#endif
n += sprintf(buf + n,
"Node %d Dirty: %8lu kB\n"
"Node %d Writeback: %8lu kB\n"
"Node %d FilePages: %8lu kB\n"
"Node %d Mapped: %8lu kB\n"
"Node %d AnonPages: %8lu kB\n"
"Node %d Shmem: %8lu kB\n"
"Node %d KernelStack: %8lu kB\n"
"Node %d PageTables: %8lu kB\n"
"Node %d NFS_Unstable: %8lu kB\n"
"Node %d Bounce: %8lu kB\n"
"Node %d WritebackTmp: %8lu kB\n"
"Node %d KReclaimable: %8lu kB\n"
"Node %d Slab: %8lu kB\n"
"Node %d SReclaimable: %8lu kB\n"
"Node %d SUnreclaim: %8lu kB\n"
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
"Node %d AnonHugePages: %8lu kB\n"
"Node %d ShmemHugePages: %8lu kB\n"
"Node %d ShmemPmdMapped: %8lu kB\n"
"Node %d FileHugePages: %8lu kB\n"
"Node %d FilePmdMapped: %8lu kB\n"
#endif
,
nid, K(node_page_state(pgdat, NR_FILE_DIRTY)),
nid, K(node_page_state(pgdat, NR_WRITEBACK)),
nid, K(node_page_state(pgdat, NR_FILE_PAGES)),
nid, K(node_page_state(pgdat, NR_FILE_MAPPED)),
nid, K(node_page_state(pgdat, NR_ANON_MAPPED)),
nid, K(i.sharedram),
nid, sum_zone_node_page_state(nid, NR_KERNEL_STACK_KB),
nid, K(sum_zone_node_page_state(nid, NR_PAGETABLE)),
nid, K(node_page_state(pgdat, NR_UNSTABLE_NFS)),
nid, K(sum_zone_node_page_state(nid, NR_BOUNCE)),
nid, K(node_page_state(pgdat, NR_WRITEBACK_TEMP)),
nid, K(sreclaimable +
node_page_state(pgdat, NR_KERNEL_MISC_RECLAIMABLE)),
nid, K(sreclaimable + sunreclaimable),
nid, K(sreclaimable),
nid, K(sunreclaimable)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
,
nid, K(node_page_state(pgdat, NR_ANON_THPS) *
HPAGE_PMD_NR),
nid, K(node_page_state(pgdat, NR_SHMEM_THPS) *
HPAGE_PMD_NR),
nid, K(node_page_state(pgdat, NR_SHMEM_PMDMAPPED) *
HPAGE_PMD_NR),
nid, K(node_page_state(pgdat, NR_FILE_THPS) *
HPAGE_PMD_NR),
nid, K(node_page_state(pgdat, NR_FILE_PMDMAPPED) *
HPAGE_PMD_NR)
#endif
);
n += hugetlb_report_node_meminfo(nid, buf + n);
return n;
}
#undef K
static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
static ssize_t node_read_numastat(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf,
"numa_hit %lu\n"
"numa_miss %lu\n"
"numa_foreign %lu\n"
"interleave_hit %lu\n"
"local_node %lu\n"
"other_node %lu\n",
sum_zone_numa_state(dev->id, NUMA_HIT),
sum_zone_numa_state(dev->id, NUMA_MISS),
sum_zone_numa_state(dev->id, NUMA_FOREIGN),
sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
sum_zone_numa_state(dev->id, NUMA_LOCAL),
sum_zone_numa_state(dev->id, NUMA_OTHER));
}
static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
static ssize_t node_read_vmstat(struct device *dev,
struct device_attribute *attr, char *buf)
{
int nid = dev->id;
struct pglist_data *pgdat = NODE_DATA(nid);
int i;
int n = 0;
for (i = 0; i < NR_VM_ZONE_STAT_ITEMS; i++)
n += sprintf(buf+n, "%s %lu\n", zone_stat_name(i),
sum_zone_node_page_state(nid, i));
#ifdef CONFIG_NUMA
for (i = 0; i < NR_VM_NUMA_STAT_ITEMS; i++)
n += sprintf(buf+n, "%s %lu\n", numa_stat_name(i),
sum_zone_numa_state(nid, i));
#endif
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
n += sprintf(buf+n, "%s %lu\n", node_stat_name(i),
node_page_state(pgdat, i));
return n;
}
static DEVICE_ATTR(vmstat, S_IRUGO, node_read_vmstat, NULL);
static ssize_t node_read_distance(struct device *dev,
struct device_attribute *attr, char *buf)
{
int nid = dev->id;
int len = 0;
int i;
/*
* buf is currently PAGE_SIZE in length and each node needs 4 chars
* at the most (distance + space or newline).
*/
BUILD_BUG_ON(MAX_NUMNODES * 4 > PAGE_SIZE);
for_each_online_node(i)
len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
len += sprintf(buf + len, "\n");
return len;
}
static DEVICE_ATTR(distance, S_IRUGO, node_read_distance, NULL);
static struct attribute *node_dev_attrs[] = {
&dev_attr_cpumap.attr,
&dev_attr_cpulist.attr,
&dev_attr_meminfo.attr,
&dev_attr_numastat.attr,
&dev_attr_distance.attr,
&dev_attr_vmstat.attr,
NULL
};
ATTRIBUTE_GROUPS(node_dev);
#ifdef CONFIG_HUGETLBFS
/*
* hugetlbfs per node attributes registration interface:
* When/if hugetlb[fs] subsystem initializes [sometime after this module],
* it will register its per node attributes for all online nodes with
* memory. It will also call register_hugetlbfs_with_node(), below, to
* register its attribute registration functions with this node driver.
* Once these hooks have been initialized, the node driver will call into
* the hugetlb module to [un]register attributes for hot-plugged nodes.
*/
static node_registration_func_t __hugetlb_register_node;
static node_registration_func_t __hugetlb_unregister_node;
static inline bool hugetlb_register_node(struct node *node)
{
if (__hugetlb_register_node &&
node_state(node->dev.id, N_MEMORY)) {
__hugetlb_register_node(node);
return true;
}
return false;
}
static inline void hugetlb_unregister_node(struct node *node)
{
if (__hugetlb_unregister_node)
__hugetlb_unregister_node(node);
}
void register_hugetlbfs_with_node(node_registration_func_t doregister,
node_registration_func_t unregister)
{
__hugetlb_register_node = doregister;
__hugetlb_unregister_node = unregister;
}
#else
static inline void hugetlb_register_node(struct node *node) {}
static inline void hugetlb_unregister_node(struct node *node) {}
#endif
static void node_device_release(struct device *dev)
{
struct node *node = to_node(dev);
#if defined(CONFIG_MEMORY_HOTPLUG_SPARSE) && defined(CONFIG_HUGETLBFS)
/*
* We schedule the work only when a memory section is
* onlined/offlined on this node. When we come here,
* all the memory on this node has been offlined,
* so we won't enqueue new work to this work.
*
* The work is using node->node_work, so we should
* flush work before freeing the memory.
*/
flush_work(&node->node_work);
#endif
kfree(node);
}
/*
* register_node - Setup a sysfs device for a node.
* @num - Node number to use when creating the device.
*
* Initialize and register the node device.
*/
static int register_node(struct node *node, int num)
{
int error;
node->dev.id = num;
node->dev.bus = &node_subsys;
node->dev.release = node_device_release;
node->dev.groups = node_dev_groups;
error = device_register(&node->dev);
if (error)
put_device(&node->dev);
else {
hugetlb_register_node(node);
compaction_register_node(node);
}
return error;
}
/**
* unregister_node - unregister a node device
* @node: node going away
*
* Unregisters a node device @node. All the devices on the node must be
* unregistered before calling this function.
*/
void unregister_node(struct node *node)
{
hugetlb_unregister_node(node); /* no-op, if memoryless node */
node_remove_accesses(node);
node_remove_caches(node);
device_unregister(&node->dev);
}
struct node *node_devices[MAX_NUMNODES];
/*
* register cpu under node
*/
int register_cpu_under_node(unsigned int cpu, unsigned int nid)
{
int ret;
struct device *obj;
if (!node_online(nid))
return 0;
obj = get_cpu_device(cpu);
if (!obj)
return 0;
ret = sysfs_create_link(&node_devices[nid]->dev.kobj,
&obj->kobj,
kobject_name(&obj->kobj));
if (ret)
return ret;
return sysfs_create_link(&obj->kobj,
&node_devices[nid]->dev.kobj,
kobject_name(&node_devices[nid]->dev.kobj));
}
/**
* register_memory_node_under_compute_node - link memory node to its compute
* node for a given access class.
* @mem_nid: Memory node number
* @cpu_nid: Cpu node number
* @access: Access class to register
*
* Description:
* For use with platforms that may have separate memory and compute nodes.
* This function will export node relationships linking which memory
* initiator nodes can access memory targets at a given ranked access
* class.
*/
int register_memory_node_under_compute_node(unsigned int mem_nid,
unsigned int cpu_nid,
unsigned access)
{
struct node *init_node, *targ_node;
struct node_access_nodes *initiator, *target;
int ret;
if (!node_online(cpu_nid) || !node_online(mem_nid))
return -ENODEV;
init_node = node_devices[cpu_nid];
targ_node = node_devices[mem_nid];
initiator = node_init_node_access(init_node, access);
target = node_init_node_access(targ_node, access);
if (!initiator || !target)
return -ENOMEM;
ret = sysfs_add_link_to_group(&initiator->dev.kobj, "targets",
&targ_node->dev.kobj,
dev_name(&targ_node->dev));
if (ret)
return ret;
ret = sysfs_add_link_to_group(&target->dev.kobj, "initiators",
&init_node->dev.kobj,
dev_name(&init_node->dev));
if (ret)
goto err;
return 0;
err:
sysfs_remove_link_from_group(&initiator->dev.kobj, "targets",
dev_name(&targ_node->dev));
return ret;
}
int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
{
struct device *obj;
if (!node_online(nid))
return 0;
obj = get_cpu_device(cpu);
if (!obj)
return 0;
sysfs_remove_link(&node_devices[nid]->dev.kobj,
kobject_name(&obj->kobj));
sysfs_remove_link(&obj->kobj,
kobject_name(&node_devices[nid]->dev.kobj));
return 0;
}
#ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
static int __ref get_nid_for_pfn(unsigned long pfn)
{
if (!pfn_valid_within(pfn))
return -1;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
if (system_state < SYSTEM_RUNNING)
return early_pfn_to_nid(pfn);
#endif
return pfn_to_nid(pfn);
}
/* register memory section under specified node if it spans that node */
static int register_mem_sect_under_node(struct memory_block *mem_blk,
void *arg)
{
unsigned long memory_block_pfns = memory_block_size_bytes() / PAGE_SIZE;
unsigned long start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
unsigned long end_pfn = start_pfn + memory_block_pfns - 1;
int ret, nid = *(int *)arg;
unsigned long pfn;
for (pfn = start_pfn; pfn <= end_pfn; pfn++) {
int page_nid;
/*
* memory block could have several absent sections from start.
* skip pfn range from absent section
*/
if (!pfn_in_present_section(pfn)) {
pfn = round_down(pfn + PAGES_PER_SECTION,
PAGES_PER_SECTION) - 1;
continue;
}
/*
* We need to check if page belongs to nid only for the boot
* case, during hotplug we know that all pages in the memory
* block belong to the same node.
*/
if (system_state == SYSTEM_BOOTING) {
page_nid = get_nid_for_pfn(pfn);
if (page_nid < 0)
continue;
if (page_nid != nid)
continue;
}
/*
* If this memory block spans multiple nodes, we only indicate
* the last processed node.
*/
mem_blk->nid = nid;
ret = sysfs_create_link_nowarn(&node_devices[nid]->dev.kobj,
&mem_blk->dev.kobj,
kobject_name(&mem_blk->dev.kobj));
if (ret)
return ret;
return sysfs_create_link_nowarn(&mem_blk->dev.kobj,
&node_devices[nid]->dev.kobj,
kobject_name(&node_devices[nid]->dev.kobj));
}
/* mem section does not span the specified node */
return 0;
}
/*
* Unregister a memory block device under the node it spans. Memory blocks
* with multiple nodes cannot be offlined and therefore also never be removed.
*/
void unregister_memory_block_under_nodes(struct memory_block *mem_blk)
{
if (mem_blk->nid == NUMA_NO_NODE)
return;
sysfs_remove_link(&node_devices[mem_blk->nid]->dev.kobj,
kobject_name(&mem_blk->dev.kobj));
sysfs_remove_link(&mem_blk->dev.kobj,
kobject_name(&node_devices[mem_blk->nid]->dev.kobj));
}
int link_mem_sections(int nid, unsigned long start_pfn, unsigned long end_pfn)
{
return walk_memory_blocks(PFN_PHYS(start_pfn),
PFN_PHYS(end_pfn - start_pfn), (void *)&nid,
register_mem_sect_under_node);
}
#ifdef CONFIG_HUGETLBFS
/*
* Handle per node hstate attribute [un]registration on transistions
* to/from memoryless state.
*/
static void node_hugetlb_work(struct work_struct *work)
{
struct node *node = container_of(work, struct node, node_work);
/*
* We only get here when a node transitions to/from memoryless state.
* We can detect which transition occurred by examining whether the
* node has memory now. hugetlb_register_node() already check this
* so we try to register the attributes. If that fails, then the
* node has transitioned to memoryless, try to unregister the
* attributes.
*/
if (!hugetlb_register_node(node))
hugetlb_unregister_node(node);
}
static void init_node_hugetlb_work(int nid)
{
INIT_WORK(&node_devices[nid]->node_work, node_hugetlb_work);
}
static int node_memory_callback(struct notifier_block *self,
unsigned long action, void *arg)
{
struct memory_notify *mnb = arg;
int nid = mnb->status_change_nid;
switch (action) {
case MEM_ONLINE:
case MEM_OFFLINE:
/*
* offload per node hstate [un]registration to a work thread
* when transitioning to/from memoryless state.
*/
if (nid != NUMA_NO_NODE)
schedule_work(&node_devices[nid]->node_work);
break;
case MEM_GOING_ONLINE:
case MEM_GOING_OFFLINE:
case MEM_CANCEL_ONLINE:
case MEM_CANCEL_OFFLINE:
default:
break;
}
return NOTIFY_OK;
}
#endif /* CONFIG_HUGETLBFS */
#endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
#if !defined(CONFIG_MEMORY_HOTPLUG_SPARSE) || \
!defined(CONFIG_HUGETLBFS)
static inline int node_memory_callback(struct notifier_block *self,
unsigned long action, void *arg)
{
return NOTIFY_OK;
}
static void init_node_hugetlb_work(int nid) { }
#endif
int __register_one_node(int nid)
{
int error;
int cpu;
node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
if (!node_devices[nid])
return -ENOMEM;
error = register_node(node_devices[nid], nid);
/* link cpu under this node */
for_each_present_cpu(cpu) {
if (cpu_to_node(cpu) == nid)
register_cpu_under_node(cpu, nid);
}
INIT_LIST_HEAD(&node_devices[nid]->access_list);
/* initialize work queue for memory hot plug */
init_node_hugetlb_work(nid);
node_init_caches(nid);
return error;
}
void unregister_one_node(int nid)
{
if (!node_devices[nid])
return;
unregister_node(node_devices[nid]);
node_devices[nid] = NULL;
}
/*
* node states attributes
*/
static ssize_t print_nodes_state(enum node_states state, char *buf)
{
int n;
n = scnprintf(buf, PAGE_SIZE - 1, "%*pbl",
nodemask_pr_args(&node_states[state]));
buf[n++] = '\n';
buf[n] = '\0';
return n;
}
struct node_attr {
struct device_attribute attr;
enum node_states state;
};
static ssize_t show_node_state(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct node_attr *na = container_of(attr, struct node_attr, attr);
return print_nodes_state(na->state, buf);
}
#define _NODE_ATTR(name, state) \
{ __ATTR(name, 0444, show_node_state, NULL), state }
static struct node_attr node_state_attr[] = {
[N_POSSIBLE] = _NODE_ATTR(possible, N_POSSIBLE),
[N_ONLINE] = _NODE_ATTR(online, N_ONLINE),
[N_NORMAL_MEMORY] = _NODE_ATTR(has_normal_memory, N_NORMAL_MEMORY),
#ifdef CONFIG_HIGHMEM
[N_HIGH_MEMORY] = _NODE_ATTR(has_high_memory, N_HIGH_MEMORY),
#endif
[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
[N_CPU] = _NODE_ATTR(has_cpu, N_CPU),
};
static struct attribute *node_state_attrs[] = {
&node_state_attr[N_POSSIBLE].attr.attr,
&node_state_attr[N_ONLINE].attr.attr,
&node_state_attr[N_NORMAL_MEMORY].attr.attr,
#ifdef CONFIG_HIGHMEM
&node_state_attr[N_HIGH_MEMORY].attr.attr,
#endif
&node_state_attr[N_MEMORY].attr.attr,
&node_state_attr[N_CPU].attr.attr,
NULL
};
static struct attribute_group memory_root_attr_group = {
.attrs = node_state_attrs,
};
static const struct attribute_group *cpu_root_attr_groups[] = {
&memory_root_attr_group,
NULL,
};
#define NODE_CALLBACK_PRI 2 /* lower than SLAB */
static int __init register_node_type(void)
{
int ret;
BUILD_BUG_ON(ARRAY_SIZE(node_state_attr) != NR_NODE_STATES);
BUILD_BUG_ON(ARRAY_SIZE(node_state_attrs)-1 != NR_NODE_STATES);
ret = subsys_system_register(&node_subsys, cpu_root_attr_groups);
if (!ret) {
static struct notifier_block node_memory_callback_nb = {
.notifier_call = node_memory_callback,
.priority = NODE_CALLBACK_PRI,
};
register_hotmemory_notifier(&node_memory_callback_nb);
}
/*
* Note: we're not going to unregister the node class if we fail
* to register the node state class attribute files.
*/
return ret;
}
postcore_initcall(register_node_type);