--- /dev/null
+/*
+ * 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 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(nid, NR_ACTIVE_ANON) +
+ node_page_state(nid, NR_ACTIVE_FILE)),
+ nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
+ node_page_state(nid, NR_INACTIVE_FILE)),
+ nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
+ nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
+ nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
+ nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
+ nid, K(node_page_state(nid, NR_UNEVICTABLE)),
+ nid, K(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"
+#endif
+ ,
+ nid, K(node_page_state(nid, NR_FILE_DIRTY)),
+ nid, K(node_page_state(nid, NR_WRITEBACK)),
+ nid, K(node_page_state(nid, NR_FILE_PAGES)),
+ nid, K(node_page_state(nid, NR_FILE_MAPPED)),
+ nid, K(node_page_state(nid, NR_ANON_PAGES)),
+ nid, K(i.sharedram),
+ nid, node_page_state(nid, NR_KERNEL_STACK) *
+ THREAD_SIZE / 1024,
+ nid, K(node_page_state(nid, NR_PAGETABLE)),
+ nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
+ nid, K(node_page_state(nid, NR_BOUNCE)),
+ nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
+ nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
+ node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
+ nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE))
+ , nid,
+ K(node_page_state(nid, NR_ANON_TRANSPARENT_HUGEPAGES) *
+ HPAGE_PMD_NR));
+#else
+ nid, K(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",
+ node_page_state(dev->id, NUMA_HIT),
+ node_page_state(dev->id, NUMA_MISS),
+ node_page_state(dev->id, NUMA_FOREIGN),
+ node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
+ node_page_state(dev->id, NUMA_LOCAL),
+ 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;
+ 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],
+ node_page_state(nid, 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 get_nid_for_pfn(unsigned long pfn)
+{
+ struct page *page;
+
+ if (!pfn_valid_within(pfn))
+ return -1;
+ 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;
+
+ 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);
Code Review / kvmfornfv.git / blobdiff