drivers/base/node.c

   1 /*
   2  * drivers/base/node.c - basic Node class support
   3  */
   4
   5 #include <linux/sysdev.h>
   6 #include <linux/module.h>
   7 #include <linux/init.h>
   8 #include <linux/mm.h>
   9 #include <linux/memory.h>
  10 #include <linux/node.h>
  11 #include <linux/hugetlb.h>
  12 #include <linux/cpumask.h>
  13 #include <linux/topology.h>
  14 #include <linux/nodemask.h>
  15 #include <linux/cpu.h>
  16 #include <linux/device.h>
  17 #include <linux/swap.h>
  18
  19 static struct sysdev_class node_class = {
  20         .name = "node",
  21 };
  22
  23
  24 static ssize_t node_read_cpumap(struct sys_device *dev, int type, char *buf)
  25 {
  26         struct node *node_dev = to_node(dev);
  27         const struct cpumask *mask = cpumask_of_node(node_dev->sysdev.id);
  28         int len;
  29
  30         /* 2008/04/07: buf currently PAGE_SIZE, need 9 chars per 32 bits. */
  31         BUILD_BUG_ON((NR_CPUS/32 * 9) > (PAGE_SIZE-1));
  32
  33         len = type?
  34                 cpulist_scnprintf(buf, PAGE_SIZE-2, mask) :
  35                 cpumask_scnprintf(buf, PAGE_SIZE-2, mask);
  36         buf[len++] = '\n';
  37         buf[len] = '\0';
  38         return len;
  39 }
  40
  41 static inline ssize_t node_read_cpumask(struct sys_device *dev,
  42                                 struct sysdev_attribute *attr, char *buf)
  43 {
  44         return node_read_cpumap(dev, 0, buf);
  45 }
  46 static inline ssize_t node_read_cpulist(struct sys_device *dev,
  47                                 struct sysdev_attribute *attr, char *buf)
  48 {
  49         return node_read_cpumap(dev, 1, buf);
  50 }
  51
  52 static SYSDEV_ATTR(cpumap,  S_IRUGO, node_read_cpumask, NULL);
  53 static SYSDEV_ATTR(cpulist, S_IRUGO, node_read_cpulist, NULL);
  54
  55 #define K(x) ((x) << (PAGE_SHIFT - 10))
  56 static ssize_t node_read_meminfo(struct sys_device * dev,
  57                         struct sysdev_attribute *attr, char * buf)
  58 {
  59         int n;
  60         int nid = dev->id;
  61         struct sysinfo i;
  62
  63         si_meminfo_node(&i, nid);
  64
  65         n = sprintf(buf, "\n"
  66                        "Node %d MemTotal:       %8lu kB\n"
  67                        "Node %d MemFree:        %8lu kB\n"
  68                        "Node %d MemUsed:        %8lu kB\n"
  69                        "Node %d Active:         %8lu kB\n"
  70                        "Node %d Inactive:       %8lu kB\n"
  71                        "Node %d Active(anon):   %8lu kB\n"
  72                        "Node %d Inactive(anon): %8lu kB\n"
  73                        "Node %d Active(file):   %8lu kB\n"
  74                        "Node %d Inactive(file): %8lu kB\n"
  75                        "Node %d Unevictable:    %8lu kB\n"
  76                        "Node %d Mlocked:        %8lu kB\n"
  77 #ifdef CONFIG_HIGHMEM
  78                        "Node %d HighTotal:      %8lu kB\n"
  79                        "Node %d HighFree:       %8lu kB\n"
  80                        "Node %d LowTotal:       %8lu kB\n"
  81                        "Node %d LowFree:        %8lu kB\n"
  82 #endif
  83                        "Node %d Dirty:          %8lu kB\n"
  84                        "Node %d Writeback:      %8lu kB\n"
  85                        "Node %d FilePages:      %8lu kB\n"
  86                        "Node %d Mapped:         %8lu kB\n"
  87                        "Node %d AnonPages:      %8lu kB\n"
  88                        "Node %d Shmem:          %8lu kB\n"
  89                        "Node %d KernelStack:    %8lu kB\n"
  90                        "Node %d PageTables:     %8lu kB\n"
  91                        "Node %d NFS_Unstable:   %8lu kB\n"
  92                        "Node %d Bounce:         %8lu kB\n"
  93                        "Node %d WritebackTmp:   %8lu kB\n"
  94                        "Node %d Slab:           %8lu kB\n"
  95                        "Node %d SReclaimable:   %8lu kB\n"
  96                        "Node %d SUnreclaim:     %8lu kB\n",
  97                        nid, K(i.totalram),
  98                        nid, K(i.freeram),
  99                        nid, K(i.totalram - i.freeram),
 100                        nid, K(node_page_state(nid, NR_ACTIVE_ANON) +
 101                                 node_page_state(nid, NR_ACTIVE_FILE)),
 102                        nid, K(node_page_state(nid, NR_INACTIVE_ANON) +
 103                                 node_page_state(nid, NR_INACTIVE_FILE)),
 104                        nid, K(node_page_state(nid, NR_ACTIVE_ANON)),
 105                        nid, K(node_page_state(nid, NR_INACTIVE_ANON)),
 106                        nid, K(node_page_state(nid, NR_ACTIVE_FILE)),
 107                        nid, K(node_page_state(nid, NR_INACTIVE_FILE)),
 108                        nid, K(node_page_state(nid, NR_UNEVICTABLE)),
 109                        nid, K(node_page_state(nid, NR_MLOCK)),
 110 #ifdef CONFIG_HIGHMEM
 111                        nid, K(i.totalhigh),
 112                        nid, K(i.freehigh),
 113                        nid, K(i.totalram - i.totalhigh),
 114                        nid, K(i.freeram - i.freehigh),
 115 #endif
 116                        nid, K(node_page_state(nid, NR_FILE_DIRTY)),
 117                        nid, K(node_page_state(nid, NR_WRITEBACK)),
 118                        nid, K(node_page_state(nid, NR_FILE_PAGES)),
 119                        nid, K(node_page_state(nid, NR_FILE_MAPPED)),
 120                        nid, K(node_page_state(nid, NR_ANON_PAGES)),
 121                        nid, K(node_page_state(nid, NR_SHMEM)),
 122                        nid, node_page_state(nid, NR_KERNEL_STACK) *
 123                                 THREAD_SIZE / 1024,
 124                        nid, K(node_page_state(nid, NR_PAGETABLE)),
 125                        nid, K(node_page_state(nid, NR_UNSTABLE_NFS)),
 126                        nid, K(node_page_state(nid, NR_BOUNCE)),
 127                        nid, K(node_page_state(nid, NR_WRITEBACK_TEMP)),
 128                        nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE) +
 129                                 node_page_state(nid, NR_SLAB_UNRECLAIMABLE)),
 130                        nid, K(node_page_state(nid, NR_SLAB_RECLAIMABLE)),
 131                        nid, K(node_page_state(nid, NR_SLAB_UNRECLAIMABLE)));
 132         n += hugetlb_report_node_meminfo(nid, buf + n);
 133         return n;
 134 }
 135
 136 #undef K
 137 static SYSDEV_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
 138
 139 static ssize_t node_read_numastat(struct sys_device * dev,
 140                                 struct sysdev_attribute *attr, char * buf)
 141 {
 142         return sprintf(buf,
 143                        "numa_hit %lu\n"
 144                        "numa_miss %lu\n"
 145                        "numa_foreign %lu\n"
 146                        "interleave_hit %lu\n"
 147                        "local_node %lu\n"
 148                        "other_node %lu\n",
 149                        node_page_state(dev->id, NUMA_HIT),
 150                        node_page_state(dev->id, NUMA_MISS),
 151                        node_page_state(dev->id, NUMA_FOREIGN),
 152                        node_page_state(dev->id, NUMA_INTERLEAVE_HIT),
 153                        node_page_state(dev->id, NUMA_LOCAL),
 154                        node_page_state(dev->id, NUMA_OTHER));
 155 }
 156 static SYSDEV_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
 157
 158 static ssize_t node_read_distance(struct sys_device * dev,
 159                         struct sysdev_attribute *attr, char * buf)
 160 {
 161         int nid = dev->id;
 162         int len = 0;
 163         int i;
 164
 165         /* buf currently PAGE_SIZE, need ~4 chars per node */
 166         BUILD_BUG_ON(MAX_NUMNODES*4 > PAGE_SIZE/2);
 167
 168         for_each_online_node(i)
 169                 len += sprintf(buf + len, "%s%d", i ? " " : "", node_distance(nid, i));
 170
 171         len += sprintf(buf + len, "\n");
 172         return len;
 173 }
 174 static SYSDEV_ATTR(distance, S_IRUGO, node_read_distance, NULL);
 175
 176 #ifdef CONFIG_HUGETLBFS
 177 /*
 178  * hugetlbfs per node attributes registration interface:
 179  * When/if hugetlb[fs] subsystem initializes [sometime after this module],
 180  * it will register its per node attributes for all online nodes with
 181  * memory.  It will also call register_hugetlbfs_with_node(), below, to
 182  * register its attribute registration functions with this node driver.
 183  * Once these hooks have been initialized, the node driver will call into
 184  * the hugetlb module to [un]register attributes for hot-plugged nodes.
 185  */
 186 static node_registration_func_t __hugetlb_register_node;
 187 static node_registration_func_t __hugetlb_unregister_node;
 188
 189 static inline void hugetlb_register_node(struct node *node)
 190 {
 191         if (__hugetlb_register_node &&
 192                         node_state(node->sysdev.id, N_HIGH_MEMORY))
 193                 __hugetlb_register_node(node);
 194 }
 195
 196 static inline void hugetlb_unregister_node(struct node *node)
 197 {
 198         if (__hugetlb_unregister_node)
 199                 __hugetlb_unregister_node(node);
 200 }
 201
 202 void register_hugetlbfs_with_node(node_registration_func_t doregister,
 203                                   node_registration_func_t unregister)
 204 {
 205         __hugetlb_register_node   = doregister;
 206         __hugetlb_unregister_node = unregister;
 207 }
 208 #else
 209 static inline void hugetlb_register_node(struct node *node) {}
 210
 211 static inline void hugetlb_unregister_node(struct node *node) {}
 212 #endif
 213
 214
 215 /*
 216  * register_node - Setup a sysfs device for a node.
 217  * @num - Node number to use when creating the device.
 218  *
 219  * Initialize and register the node device.
 220  */
 221 int register_node(struct node *node, int num, struct node *parent)
 222 {
 223         int error;
 224
 225         node->sysdev.id = num;
 226         node->sysdev.cls = &node_class;
 227         error = sysdev_register(&node->sysdev);
 228
 229         if (!error){
 230                 sysdev_create_file(&node->sysdev, &attr_cpumap);
 231                 sysdev_create_file(&node->sysdev, &attr_cpulist);
 232                 sysdev_create_file(&node->sysdev, &attr_meminfo);
 233                 sysdev_create_file(&node->sysdev, &attr_numastat);
 234                 sysdev_create_file(&node->sysdev, &attr_distance);
 235
 236                 scan_unevictable_register_node(node);
 237
 238                 hugetlb_register_node(node);
 239         }
 240         return error;
 241 }
 242
 243 /**
 244  * unregister_node - unregister a node device
 245  * @node: node going away
 246  *
 247  * Unregisters a node device @node.  All the devices on the node must be
 248  * unregistered before calling this function.
 249  */
 250 void unregister_node(struct node *node)
 251 {
 252         sysdev_remove_file(&node->sysdev, &attr_cpumap);
 253         sysdev_remove_file(&node->sysdev, &attr_cpulist);
 254         sysdev_remove_file(&node->sysdev, &attr_meminfo);
 255         sysdev_remove_file(&node->sysdev, &attr_numastat);
 256         sysdev_remove_file(&node->sysdev, &attr_distance);
 257
 258         scan_unevictable_unregister_node(node);
 259         hugetlb_unregister_node(node);          /* no-op, if memoryless node */
 260
 261         sysdev_unregister(&node->sysdev);
 262 }
 263
 264 struct node node_devices[MAX_NUMNODES];
 265
 266 /*
 267  * register cpu under node
 268  */
 269 int register_cpu_under_node(unsigned int cpu, unsigned int nid)
 270 {
 271         if (node_online(nid)) {
 272                 struct sys_device *obj = get_cpu_sysdev(cpu);
 273                 if (!obj)
 274                         return 0;
 275                 return sysfs_create_link(&node_devices[nid].sysdev.kobj,
 276                                          &obj->kobj,
 277                                          kobject_name(&obj->kobj));
 278          }
 279
 280         return 0;
 281 }
 282
 283 int unregister_cpu_under_node(unsigned int cpu, unsigned int nid)
 284 {
 285         if (node_online(nid)) {
 286                 struct sys_device *obj = get_cpu_sysdev(cpu);
 287                 if (obj)
 288                         sysfs_remove_link(&node_devices[nid].sysdev.kobj,
 289                                          kobject_name(&obj->kobj));
 290         }
 291         return 0;
 292 }
 293
 294 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 295 #define page_initialized(page)  (page->lru.next)
 296
 297 static int get_nid_for_pfn(unsigned long pfn)
 298 {
 299         struct page *page;
 300
 301         if (!pfn_valid_within(pfn))
 302                 return -1;
 303         page = pfn_to_page(pfn);
 304         if (!page_initialized(page))
 305                 return -1;
 306         return pfn_to_nid(pfn);
 307 }
 308
 309 /* register memory section under specified node if it spans that node */
 310 int register_mem_sect_under_node(struct memory_block *mem_blk, int nid)
 311 {
 312         unsigned long pfn, sect_start_pfn, sect_end_pfn;
 313
 314         if (!mem_blk)
 315                 return -EFAULT;
 316         if (!node_online(nid))
 317                 return 0;
 318         sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index);
 319         sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
 320         for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
 321                 int page_nid;
 322
 323                 page_nid = get_nid_for_pfn(pfn);
 324                 if (page_nid < 0)
 325                         continue;
 326                 if (page_nid != nid)
 327                         continue;
 328                 return sysfs_create_link_nowarn(&node_devices[nid].sysdev.kobj,
 329                                         &mem_blk->sysdev.kobj,
 330                                         kobject_name(&mem_blk->sysdev.kobj));
 331         }
 332         /* mem section does not span the specified node */
 333         return 0;
 334 }
 335
 336 /* unregister memory section under all nodes that it spans */
 337 int unregister_mem_sect_under_nodes(struct memory_block *mem_blk)
 338 {
 339         nodemask_t unlinked_nodes;
 340         unsigned long pfn, sect_start_pfn, sect_end_pfn;
 341
 342         if (!mem_blk)
 343                 return -EFAULT;
 344         nodes_clear(unlinked_nodes);
 345         sect_start_pfn = section_nr_to_pfn(mem_blk->phys_index);
 346         sect_end_pfn = sect_start_pfn + PAGES_PER_SECTION - 1;
 347         for (pfn = sect_start_pfn; pfn <= sect_end_pfn; pfn++) {
 348                 int nid;
 349
 350                 nid = get_nid_for_pfn(pfn);
 351                 if (nid < 0)
 352                         continue;
 353                 if (!node_online(nid))
 354                         continue;
 355                 if (node_test_and_set(nid, unlinked_nodes))
 356                         continue;
 357                 sysfs_remove_link(&node_devices[nid].sysdev.kobj,
 358                          kobject_name(&mem_blk->sysdev.kobj));
 359         }
 360         return 0;
 361 }
 362
 363 static int link_mem_sections(int nid)
 364 {
 365         unsigned long start_pfn = NODE_DATA(nid)->node_start_pfn;
 366         unsigned long end_pfn = start_pfn + NODE_DATA(nid)->node_spanned_pages;
 367         unsigned long pfn;
 368         int err = 0;
 369
 370         for (pfn = start_pfn; pfn < end_pfn; pfn += PAGES_PER_SECTION) {
 371                 unsigned long section_nr = pfn_to_section_nr(pfn);
 372                 struct mem_section *mem_sect;
 373                 struct memory_block *mem_blk;
 374                 int ret;
 375
 376                 if (!present_section_nr(section_nr))
 377                         continue;
 378                 mem_sect = __nr_to_section(section_nr);
 379                 mem_blk = find_memory_block(mem_sect);
 380                 ret = register_mem_sect_under_node(mem_blk, nid);
 381                 if (!err)
 382                         err = ret;
 383
 384                 /* discard ref obtained in find_memory_block() */
 385                 kobject_put(&mem_blk->sysdev.kobj);
 386         }
 387         return err;
 388 }
 389
 390 /*
 391  * Handle per node hstate attribute [un]registration on transistions
 392  * to/from memoryless state.
 393  */
 394
 395 static int node_memory_callback(struct notifier_block *self,
 396                                 unsigned long action, void *arg)
 397 {
 398         struct memory_notify *mnb = arg;
 399         int nid = mnb->status_change_nid;
 400
 401         switch (action) {
 402         case MEM_ONLINE:    /* memory successfully brought online */
 403                 if (nid != NUMA_NO_NODE)
 404                         hugetlb_register_node(&node_devices[nid]);
 405                 break;
 406         case MEM_OFFLINE:   /* or offline */
 407                 if (nid != NUMA_NO_NODE)
 408                         hugetlb_unregister_node(&node_devices[nid]);
 409                 break;
 410         case MEM_GOING_ONLINE:
 411         case MEM_GOING_OFFLINE:
 412         case MEM_CANCEL_ONLINE:
 413         case MEM_CANCEL_OFFLINE:
 414         default:
 415                 break;
 416         }
 417
 418         return NOTIFY_OK;
 419 }
 420 #else
 421 static int link_mem_sections(int nid) { return 0; }
 422
 423 static inline int node_memory_callback(struct notifier_block *self,
 424                                 unsigned long action, void *arg)
 425 {
 426         return NOTIFY_OK;
 427 }
 428 #endif /* CONFIG_MEMORY_HOTPLUG_SPARSE */
 429
 430 int register_one_node(int nid)
 431 {
 432         int error = 0;
 433         int cpu;
 434
 435         if (node_online(nid)) {
 436                 int p_node = parent_node(nid);
 437                 struct node *parent = NULL;
 438
 439                 if (p_node != nid)
 440                         parent = &node_devices[p_node];
 441
 442                 error = register_node(&node_devices[nid], nid, parent);
 443
 444                 /* link cpu under this node */
 445                 for_each_present_cpu(cpu) {
 446                         if (cpu_to_node(cpu) == nid)
 447                                 register_cpu_under_node(cpu, nid);
 448                 }
 449
 450                 /* link memory sections under this node */
 451                 error = link_mem_sections(nid);
 452         }
 453
 454         return error;
 455
 456 }
 457
 458 void unregister_one_node(int nid)
 459 {
 460         unregister_node(&node_devices[nid]);
 461 }
 462
 463 /*
 464  * node states attributes
 465  */
 466
 467 static ssize_t print_nodes_state(enum node_states state, char *buf)
 468 {
 469         int n;
 470
 471         n = nodelist_scnprintf(buf, PAGE_SIZE, node_states[state]);
 472         if (n > 0 && PAGE_SIZE > n + 1) {
 473                 *(buf + n++) = '\n';
 474                 *(buf + n++) = '\0';
 475         }
 476         return n;
 477 }
 478
 479 static ssize_t print_nodes_possible(struct sysdev_class *class, char *buf)
 480 {
 481         return print_nodes_state(N_POSSIBLE, buf);
 482 }
 483
 484 static ssize_t print_nodes_online(struct sysdev_class *class, char *buf)
 485 {
 486         return print_nodes_state(N_ONLINE, buf);
 487 }
 488
 489 static ssize_t print_nodes_has_normal_memory(struct sysdev_class *class,
 490                                                 char *buf)
 491 {
 492         return print_nodes_state(N_NORMAL_MEMORY, buf);
 493 }
 494
 495 static ssize_t print_nodes_has_cpu(struct sysdev_class *class, char *buf)
 496 {
 497         return print_nodes_state(N_CPU, buf);
 498 }
 499
 500 static SYSDEV_CLASS_ATTR(possible, 0444, print_nodes_possible, NULL);
 501 static SYSDEV_CLASS_ATTR(online, 0444, print_nodes_online, NULL);
 502 static SYSDEV_CLASS_ATTR(has_normal_memory, 0444, print_nodes_has_normal_memory,
 503                                                                         NULL);
 504 static SYSDEV_CLASS_ATTR(has_cpu, 0444, print_nodes_has_cpu, NULL);
 505
 506 #ifdef CONFIG_HIGHMEM
 507 static ssize_t print_nodes_has_high_memory(struct sysdev_class *class,
 508                                                  char *buf)
 509 {
 510         return print_nodes_state(N_HIGH_MEMORY, buf);
 511 }
 512
 513 static SYSDEV_CLASS_ATTR(has_high_memory, 0444, print_nodes_has_high_memory,
 514                                                                          NULL);
 515 #endif
 516
 517 struct sysdev_class_attribute *node_state_attr[] = {
 518         &attr_possible,
 519         &attr_online,
 520         &attr_has_normal_memory,
 521 #ifdef CONFIG_HIGHMEM
 522         &attr_has_high_memory,
 523 #endif
 524         &attr_has_cpu,
 525 };
 526
 527 static int node_states_init(void)
 528 {
 529         int i;
 530         int err = 0;
 531
 532         for (i = 0;  i < NR_NODE_STATES; i++) {
 533                 int ret;
 534                 ret = sysdev_class_create_file(&node_class, node_state_attr[i]);
 535                 if (!err)
 536                         err = ret;
 537         }
 538         return err;
 539 }
 540
 541 #define NODE_CALLBACK_PRI       2       /* lower than SLAB */
 542 static int __init register_node_type(void)
 543 {
 544         int ret;
 545
 546         ret = sysdev_class_register(&node_class);
 547         if (!ret) {
 548                 ret = node_states_init();
 549                 hotplug_memory_notifier(node_memory_callback,
 550                                         NODE_CALLBACK_PRI);
 551         }
 552
 553         /*
 554          * Note:  we're not going to unregister the node class if we fail
 555          * to register the node state class attribute files.
 556          */
 557         return ret;
 558 }
 559 postcore_initcall(register_node_type);