/*
* 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/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)
{
struct node *node_dev = to_node(dev);
const struct cpumask *mask = cpumask_of_node(node_dev->dev.id);
/* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
return cpumap_print_to_pagebuf(list, buf, mask);
}
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);
#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;
si_meminfo_node(&i, nid);
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 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"
#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(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE) +
sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
nid, K(sum_zone_node_page_state(nid, NR_SLAB_RECLAIMABLE)),
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
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));
#else
nid, K(sum_zone_node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
#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_node_page_state(dev->id, NUMA_HIT),
sum_zone_node_page_state(dev->id, NUMA_MISS),
sum_zone_node_page_state(dev->id, NUMA_FOREIGN),
sum_zone_node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
sum_zone_node_page_state(dev->id, NUMA_LOCAL),
sum_zone_node_page_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", vmstat_text[i],
sum_zone_node_page_state(nid, i));
for (i = 0; i < NR_VM_NODE_STAT_ITEMS; i++)
n += sprintf(buf+n, "%s %lu\n",
vmstat_text[i + NR_VM_ZONE_STAT_ITEMS],
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, struct node *parent)
{
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){
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 */
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));
}
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
#define page_initialized(page) (page->lru.next)
static int __ref get_nid_for_pfn(unsigned long pfn)
{
struct page *page;
if (!pfn_valid_within(pfn))
return -1;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
if (system_state == SYSTEM_BOOTING)
return early_pfn_to_nid(pfn);
#endif
page = pfn_to_page(pfn);
if (!page_initialized(page))
return -1;
return pfn_to_nid(pfn);
}
/* register memory section under specified node if it spans that node */
int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
{
int ret;
unsigned long pfn, sect_start_pfn, sect_end_pfn;
if (!mem_blk)
return -EFAULT;
if (!node_online(nid))
return 0;
sect_start_pfn = section_nr_to_pfn(mem_blk->start_section_nr);
sect_end_pfn = section_nr_to_pfn(mem_blk->end_section_nr);
sect_end_pfn += PAGES_PER_SECTION - 1;
for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
int page_nid;
/*
* memory block could have several absent sections from start.
* skip pfn range from absent section
*/
if (!pfn_present(pfn)) {
pfn = round_down(pfn + PAGES_PER_SECTION,
PAGES_PER_SECTION) - 1;
continue;
}
page_nid = get_nid_for_pfn(pfn);
if (page_nid < 0)
continue;
if (page_nid != nid)
continue;
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 memory section under all nodes that it spans */
int unregister_mem_sect_under_nodes(struct memory_block *mem_blk,
unsigned long phys_index)
{
NODEMASK_ALLOC(nodemask_t, unlinked_nodes, GFP_KERNEL);
unsigned long pfn, sect_start_pfn, sect_end_pfn;
if (!mem_blk) {
NODEMASK_FREE(unlinked_nodes);
return -EFAULT;
}
if (!unlinked_nodes)
return -ENOMEM;
nodes_clear(*unlinked_nodes);
sect_start_pfn = section_nr_to_pfn(phys_index);
sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
int nid;
nid = get_nid_for_pfn(pfn);
if (nid < 0)
continue;
if (!node_online(nid))
continue;
if (node_test_and_set(nid, *unlinked_nodes))
continue;
sysfs_remove_link(&node_devices[nid]->dev.kobj,
kobject_name(&mem_blk->dev.kobj));
sysfs_remove_link(&mem_blk->dev.kobj,
kobject_name(&node_devices[nid]->dev.kobj));
}
NODEMASK_FREE(unlinked_nodes);
return 0;
}
static int link_mem_sections(int nid)
{
unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
unsigned long pfn;
struct memory_block *mem_blk = NULL;
int err = 0;
for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
unsigned long section_nr = pfn_to_section_nr(pfn);
struct mem_section *mem_sect;
int ret;
if (!present_section_nr(section_nr))
continue;
mem_sect = __nr_to_section(section_nr);
/* same memblock ? */
if (mem_blk)
if ((section_nr >= mem_blk->start_section_nr) &&
(section_nr <= mem_blk->end_section_nr))
continue;
mem_blk = find_memory_block_hinted(mem_sect, mem_blk);
ret = register_mem_sect_under_node(mem_blk, nid);
if (!err)
err = ret;
/* discard ref obtained in find_memory_block() */
}
if (mem_blk)
kobject_put(&mem_blk->dev.kobj);
return err;
}
#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 */
#else /* !CONFIG_MEMORY_HOTPLUG_SPARSE */
static int link_mem_sections(int nid) { return 0; }
#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 = 0;
int cpu;
if (node_online(nid)) {
int p_node = parent_node(nid);
struct node *parent = NULL;
if (p_node != nid)
parent = node_devices[p_node];
node_devices[nid] = kzalloc(sizeof(struct node), GFP_KERNEL);
if (!node_devices[nid])
return -ENOMEM;
error = register_node(node_devices[nid], nid, parent);
/* link cpu under this node */
for_each_present_cpu(cpu) {
if (cpu_to_node(cpu) == nid)
register_cpu_under_node(cpu, nid);
}
/* link memory sections under this node */
error = link_mem_sections(nid);
/* initialize work queue for memory hot plug */
init_node_hugetlb_work(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
#ifdef CONFIG_MOVABLE_NODE
[N_MEMORY] = _NODE_ATTR(has_memory, N_MEMORY),
#endif
[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
#ifdef CONFIG_MOVABLE_NODE
&node_state_attr[N_MEMORY].attr.attr,
#endif
&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);
