page_alloc.c revision 7f33d49a2ed546e01f7b1d0607661810f2421859
1/* 2 * linux/mm/page_alloc.c 3 * 4 * Manages the free list, the system allocates free pages here. 5 * Note that kmalloc() lives in slab.c 6 * 7 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds 8 * Swap reorganised 29.12.95, Stephen Tweedie 9 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 10 * Reshaped it to be a zoned allocator, Ingo Molnar, Red Hat, 1999 11 * Discontiguous memory support, Kanoj Sarcar, SGI, Nov 1999 12 * Zone balancing, Kanoj Sarcar, SGI, Jan 2000 13 * Per cpu hot/cold page lists, bulk allocation, Martin J. Bligh, Sept 2002 14 * (lots of bits borrowed from Ingo Molnar & Andrew Morton) 15 */ 16 17#include <linux/stddef.h> 18#include <linux/mm.h> 19#include <linux/swap.h> 20#include <linux/interrupt.h> 21#include <linux/pagemap.h> 22#include <linux/jiffies.h> 23#include <linux/bootmem.h> 24#include <linux/compiler.h> 25#include <linux/kernel.h> 26#include <linux/module.h> 27#include <linux/suspend.h> 28#include <linux/pagevec.h> 29#include <linux/blkdev.h> 30#include <linux/slab.h> 31#include <linux/oom.h> 32#include <linux/notifier.h> 33#include <linux/topology.h> 34#include <linux/sysctl.h> 35#include <linux/cpu.h> 36#include <linux/cpuset.h> 37#include <linux/memory_hotplug.h> 38#include <linux/nodemask.h> 39#include <linux/vmalloc.h> 40#include <linux/mempolicy.h> 41#include <linux/stop_machine.h> 42#include <linux/sort.h> 43#include <linux/pfn.h> 44#include <linux/backing-dev.h> 45#include <linux/fault-inject.h> 46#include <linux/page-isolation.h> 47#include <linux/page_cgroup.h> 48#include <linux/debugobjects.h> 49#include <linux/kmemleak.h> 50 51#include <asm/tlbflush.h> 52#include <asm/div64.h> 53#include "internal.h" 54 55/* 56 * Array of node states. 57 */ 58nodemask_t node_states[NR_NODE_STATES] __read_mostly = { 59 [N_POSSIBLE] = NODE_MASK_ALL, 60 [N_ONLINE] = { { [0] = 1UL } }, 61#ifndef CONFIG_NUMA 62 [N_NORMAL_MEMORY] = { { [0] = 1UL } }, 63#ifdef CONFIG_HIGHMEM 64 [N_HIGH_MEMORY] = { { [0] = 1UL } }, 65#endif 66 [N_CPU] = { { [0] = 1UL } }, 67#endif /* NUMA */ 68}; 69EXPORT_SYMBOL(node_states); 70 71unsigned long totalram_pages __read_mostly; 72unsigned long totalreserve_pages __read_mostly; 73unsigned long highest_memmap_pfn __read_mostly; 74int percpu_pagelist_fraction; 75 76#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE 77int pageblock_order __read_mostly; 78#endif 79 80static void __free_pages_ok(struct page *page, unsigned int order); 81 82/* 83 * results with 256, 32 in the lowmem_reserve sysctl: 84 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high) 85 * 1G machine -> (16M dma, 784M normal, 224M high) 86 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA 87 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL 88 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA 89 * 90 * TBD: should special case ZONE_DMA32 machines here - in those we normally 91 * don't need any ZONE_NORMAL reservation 92 */ 93int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 94#ifdef CONFIG_ZONE_DMA 95 256, 96#endif 97#ifdef CONFIG_ZONE_DMA32 98 256, 99#endif 100#ifdef CONFIG_HIGHMEM 101 32, 102#endif 103 32, 104}; 105 106EXPORT_SYMBOL(totalram_pages); 107 108static char * const zone_names[MAX_NR_ZONES] = { 109#ifdef CONFIG_ZONE_DMA 110 "DMA", 111#endif 112#ifdef CONFIG_ZONE_DMA32 113 "DMA32", 114#endif 115 "Normal", 116#ifdef CONFIG_HIGHMEM 117 "HighMem", 118#endif 119 "Movable", 120}; 121 122int min_free_kbytes = 1024; 123 124unsigned long __meminitdata nr_kernel_pages; 125unsigned long __meminitdata nr_all_pages; 126static unsigned long __meminitdata dma_reserve; 127 128#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 129 /* 130 * MAX_ACTIVE_REGIONS determines the maximum number of distinct 131 * ranges of memory (RAM) that may be registered with add_active_range(). 132 * Ranges passed to add_active_range() will be merged if possible 133 * so the number of times add_active_range() can be called is 134 * related to the number of nodes and the number of holes 135 */ 136 #ifdef CONFIG_MAX_ACTIVE_REGIONS 137 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */ 138 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS 139 #else 140 #if MAX_NUMNODES >= 32 141 /* If there can be many nodes, allow up to 50 holes per node */ 142 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50) 143 #else 144 /* By default, allow up to 256 distinct regions */ 145 #define MAX_ACTIVE_REGIONS 256 146 #endif 147 #endif 148 149 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS]; 150 static int __meminitdata nr_nodemap_entries; 151 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES]; 152 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES]; 153 static unsigned long __initdata required_kernelcore; 154 static unsigned long __initdata required_movablecore; 155 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES]; 156 157 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ 158 int movable_zone; 159 EXPORT_SYMBOL(movable_zone); 160#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 161 162#if MAX_NUMNODES > 1 163int nr_node_ids __read_mostly = MAX_NUMNODES; 164int nr_online_nodes __read_mostly = 1; 165EXPORT_SYMBOL(nr_node_ids); 166EXPORT_SYMBOL(nr_online_nodes); 167#endif 168 169int page_group_by_mobility_disabled __read_mostly; 170 171static void set_pageblock_migratetype(struct page *page, int migratetype) 172{ 173 174 if (unlikely(page_group_by_mobility_disabled)) 175 migratetype = MIGRATE_UNMOVABLE; 176 177 set_pageblock_flags_group(page, (unsigned long)migratetype, 178 PB_migrate, PB_migrate_end); 179} 180 181bool oom_killer_disabled __read_mostly; 182 183#ifdef CONFIG_DEBUG_VM 184static int page_outside_zone_boundaries(struct zone *zone, struct page *page) 185{ 186 int ret = 0; 187 unsigned seq; 188 unsigned long pfn = page_to_pfn(page); 189 190 do { 191 seq = zone_span_seqbegin(zone); 192 if (pfn >= zone->zone_start_pfn + zone->spanned_pages) 193 ret = 1; 194 else if (pfn < zone->zone_start_pfn) 195 ret = 1; 196 } while (zone_span_seqretry(zone, seq)); 197 198 return ret; 199} 200 201static int page_is_consistent(struct zone *zone, struct page *page) 202{ 203 if (!pfn_valid_within(page_to_pfn(page))) 204 return 0; 205 if (zone != page_zone(page)) 206 return 0; 207 208 return 1; 209} 210/* 211 * Temporary debugging check for pages not lying within a given zone. 212 */ 213static int bad_range(struct zone *zone, struct page *page) 214{ 215 if (page_outside_zone_boundaries(zone, page)) 216 return 1; 217 if (!page_is_consistent(zone, page)) 218 return 1; 219 220 return 0; 221} 222#else 223static inline int bad_range(struct zone *zone, struct page *page) 224{ 225 return 0; 226} 227#endif 228 229static void bad_page(struct page *page) 230{ 231 static unsigned long resume; 232 static unsigned long nr_shown; 233 static unsigned long nr_unshown; 234 235 /* 236 * Allow a burst of 60 reports, then keep quiet for that minute; 237 * or allow a steady drip of one report per second. 238 */ 239 if (nr_shown == 60) { 240 if (time_before(jiffies, resume)) { 241 nr_unshown++; 242 goto out; 243 } 244 if (nr_unshown) { 245 printk(KERN_ALERT 246 "BUG: Bad page state: %lu messages suppressed\n", 247 nr_unshown); 248 nr_unshown = 0; 249 } 250 nr_shown = 0; 251 } 252 if (nr_shown++ == 0) 253 resume = jiffies + 60 * HZ; 254 255 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n", 256 current->comm, page_to_pfn(page)); 257 printk(KERN_ALERT 258 "page:%p flags:%p count:%d mapcount:%d mapping:%p index:%lx\n", 259 page, (void *)page->flags, page_count(page), 260 page_mapcount(page), page->mapping, page->index); 261 262 dump_stack(); 263out: 264 /* Leave bad fields for debug, except PageBuddy could make trouble */ 265 __ClearPageBuddy(page); 266 add_taint(TAINT_BAD_PAGE); 267} 268 269/* 270 * Higher-order pages are called "compound pages". They are structured thusly: 271 * 272 * The first PAGE_SIZE page is called the "head page". 273 * 274 * The remaining PAGE_SIZE pages are called "tail pages". 275 * 276 * All pages have PG_compound set. All pages have their ->private pointing at 277 * the head page (even the head page has this). 278 * 279 * The first tail page's ->lru.next holds the address of the compound page's 280 * put_page() function. Its ->lru.prev holds the order of allocation. 281 * This usage means that zero-order pages may not be compound. 282 */ 283 284static void free_compound_page(struct page *page) 285{ 286 __free_pages_ok(page, compound_order(page)); 287} 288 289void prep_compound_page(struct page *page, unsigned long order) 290{ 291 int i; 292 int nr_pages = 1 << order; 293 294 set_compound_page_dtor(page, free_compound_page); 295 set_compound_order(page, order); 296 __SetPageHead(page); 297 for (i = 1; i < nr_pages; i++) { 298 struct page *p = page + i; 299 300 __SetPageTail(p); 301 p->first_page = page; 302 } 303} 304 305static int destroy_compound_page(struct page *page, unsigned long order) 306{ 307 int i; 308 int nr_pages = 1 << order; 309 int bad = 0; 310 311 if (unlikely(compound_order(page) != order) || 312 unlikely(!PageHead(page))) { 313 bad_page(page); 314 bad++; 315 } 316 317 __ClearPageHead(page); 318 319 for (i = 1; i < nr_pages; i++) { 320 struct page *p = page + i; 321 322 if (unlikely(!PageTail(p) || (p->first_page != page))) { 323 bad_page(page); 324 bad++; 325 } 326 __ClearPageTail(p); 327 } 328 329 return bad; 330} 331 332static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags) 333{ 334 int i; 335 336 /* 337 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO 338 * and __GFP_HIGHMEM from hard or soft interrupt context. 339 */ 340 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt()); 341 for (i = 0; i < (1 << order); i++) 342 clear_highpage(page + i); 343} 344 345static inline void set_page_order(struct page *page, int order) 346{ 347 set_page_private(page, order); 348 __SetPageBuddy(page); 349} 350 351static inline void rmv_page_order(struct page *page) 352{ 353 __ClearPageBuddy(page); 354 set_page_private(page, 0); 355} 356 357/* 358 * Locate the struct page for both the matching buddy in our 359 * pair (buddy1) and the combined O(n+1) page they form (page). 360 * 361 * 1) Any buddy B1 will have an order O twin B2 which satisfies 362 * the following equation: 363 * B2 = B1 ^ (1 << O) 364 * For example, if the starting buddy (buddy2) is #8 its order 365 * 1 buddy is #10: 366 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 367 * 368 * 2) Any buddy B will have an order O+1 parent P which 369 * satisfies the following equation: 370 * P = B & ~(1 << O) 371 * 372 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER 373 */ 374static inline struct page * 375__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order) 376{ 377 unsigned long buddy_idx = page_idx ^ (1 << order); 378 379 return page + (buddy_idx - page_idx); 380} 381 382static inline unsigned long 383__find_combined_index(unsigned long page_idx, unsigned int order) 384{ 385 return (page_idx & ~(1 << order)); 386} 387 388/* 389 * This function checks whether a page is free && is the buddy 390 * we can do coalesce a page and its buddy if 391 * (a) the buddy is not in a hole && 392 * (b) the buddy is in the buddy system && 393 * (c) a page and its buddy have the same order && 394 * (d) a page and its buddy are in the same zone. 395 * 396 * For recording whether a page is in the buddy system, we use PG_buddy. 397 * Setting, clearing, and testing PG_buddy is serialized by zone->lock. 398 * 399 * For recording page's order, we use page_private(page). 400 */ 401static inline int page_is_buddy(struct page *page, struct page *buddy, 402 int order) 403{ 404 if (!pfn_valid_within(page_to_pfn(buddy))) 405 return 0; 406 407 if (page_zone_id(page) != page_zone_id(buddy)) 408 return 0; 409 410 if (PageBuddy(buddy) && page_order(buddy) == order) { 411 VM_BUG_ON(page_count(buddy) != 0); 412 return 1; 413 } 414 return 0; 415} 416 417/* 418 * Freeing function for a buddy system allocator. 419 * 420 * The concept of a buddy system is to maintain direct-mapped table 421 * (containing bit values) for memory blocks of various "orders". 422 * The bottom level table contains the map for the smallest allocatable 423 * units of memory (here, pages), and each level above it describes 424 * pairs of units from the levels below, hence, "buddies". 425 * At a high level, all that happens here is marking the table entry 426 * at the bottom level available, and propagating the changes upward 427 * as necessary, plus some accounting needed to play nicely with other 428 * parts of the VM system. 429 * At each level, we keep a list of pages, which are heads of continuous 430 * free pages of length of (1 << order) and marked with PG_buddy. Page's 431 * order is recorded in page_private(page) field. 432 * So when we are allocating or freeing one, we can derive the state of the 433 * other. That is, if we allocate a small block, and both were 434 * free, the remainder of the region must be split into blocks. 435 * If a block is freed, and its buddy is also free, then this 436 * triggers coalescing into a block of larger size. 437 * 438 * -- wli 439 */ 440 441static inline void __free_one_page(struct page *page, 442 struct zone *zone, unsigned int order, 443 int migratetype) 444{ 445 unsigned long page_idx; 446 447 if (unlikely(PageCompound(page))) 448 if (unlikely(destroy_compound_page(page, order))) 449 return; 450 451 VM_BUG_ON(migratetype == -1); 452 453 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); 454 455 VM_BUG_ON(page_idx & ((1 << order) - 1)); 456 VM_BUG_ON(bad_range(zone, page)); 457 458 while (order < MAX_ORDER-1) { 459 unsigned long combined_idx; 460 struct page *buddy; 461 462 buddy = __page_find_buddy(page, page_idx, order); 463 if (!page_is_buddy(page, buddy, order)) 464 break; 465 466 /* Our buddy is free, merge with it and move up one order. */ 467 list_del(&buddy->lru); 468 zone->free_area[order].nr_free--; 469 rmv_page_order(buddy); 470 combined_idx = __find_combined_index(page_idx, order); 471 page = page + (combined_idx - page_idx); 472 page_idx = combined_idx; 473 order++; 474 } 475 set_page_order(page, order); 476 list_add(&page->lru, 477 &zone->free_area[order].free_list[migratetype]); 478 zone->free_area[order].nr_free++; 479} 480 481#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT 482/* 483 * free_page_mlock() -- clean up attempts to free and mlocked() page. 484 * Page should not be on lru, so no need to fix that up. 485 * free_pages_check() will verify... 486 */ 487static inline void free_page_mlock(struct page *page) 488{ 489 __ClearPageMlocked(page); 490 __dec_zone_page_state(page, NR_MLOCK); 491 __count_vm_event(UNEVICTABLE_MLOCKFREED); 492} 493#else 494static void free_page_mlock(struct page *page) { } 495#endif 496 497static inline int free_pages_check(struct page *page) 498{ 499 if (unlikely(page_mapcount(page) | 500 (page->mapping != NULL) | 501 (atomic_read(&page->_count) != 0) | 502 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) { 503 bad_page(page); 504 return 1; 505 } 506 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP) 507 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; 508 return 0; 509} 510 511/* 512 * Frees a list of pages. 513 * Assumes all pages on list are in same zone, and of same order. 514 * count is the number of pages to free. 515 * 516 * If the zone was previously in an "all pages pinned" state then look to 517 * see if this freeing clears that state. 518 * 519 * And clear the zone's pages_scanned counter, to hold off the "all pages are 520 * pinned" detection logic. 521 */ 522static void free_pages_bulk(struct zone *zone, int count, 523 struct list_head *list, int order) 524{ 525 spin_lock(&zone->lock); 526 zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); 527 zone->pages_scanned = 0; 528 529 __mod_zone_page_state(zone, NR_FREE_PAGES, count << order); 530 while (count--) { 531 struct page *page; 532 533 VM_BUG_ON(list_empty(list)); 534 page = list_entry(list->prev, struct page, lru); 535 /* have to delete it as __free_one_page list manipulates */ 536 list_del(&page->lru); 537 __free_one_page(page, zone, order, page_private(page)); 538 } 539 spin_unlock(&zone->lock); 540} 541 542static void free_one_page(struct zone *zone, struct page *page, int order, 543 int migratetype) 544{ 545 spin_lock(&zone->lock); 546 zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE); 547 zone->pages_scanned = 0; 548 549 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order); 550 __free_one_page(page, zone, order, migratetype); 551 spin_unlock(&zone->lock); 552} 553 554static void __free_pages_ok(struct page *page, unsigned int order) 555{ 556 unsigned long flags; 557 int i; 558 int bad = 0; 559 int clearMlocked = PageMlocked(page); 560 561 for (i = 0 ; i < (1 << order) ; ++i) 562 bad += free_pages_check(page + i); 563 if (bad) 564 return; 565 566 if (!PageHighMem(page)) { 567 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order); 568 debug_check_no_obj_freed(page_address(page), 569 PAGE_SIZE << order); 570 } 571 arch_free_page(page, order); 572 kernel_map_pages(page, 1 << order, 0); 573 574 local_irq_save(flags); 575 if (unlikely(clearMlocked)) 576 free_page_mlock(page); 577 __count_vm_events(PGFREE, 1 << order); 578 free_one_page(page_zone(page), page, order, 579 get_pageblock_migratetype(page)); 580 local_irq_restore(flags); 581} 582 583/* 584 * permit the bootmem allocator to evade page validation on high-order frees 585 */ 586void __meminit __free_pages_bootmem(struct page *page, unsigned int order) 587{ 588 if (order == 0) { 589 __ClearPageReserved(page); 590 set_page_count(page, 0); 591 set_page_refcounted(page); 592 __free_page(page); 593 } else { 594 int loop; 595 596 prefetchw(page); 597 for (loop = 0; loop < BITS_PER_LONG; loop++) { 598 struct page *p = &page[loop]; 599 600 if (loop + 1 < BITS_PER_LONG) 601 prefetchw(p + 1); 602 __ClearPageReserved(p); 603 set_page_count(p, 0); 604 } 605 606 set_page_refcounted(page); 607 __free_pages(page, order); 608 } 609} 610 611 612/* 613 * The order of subdivision here is critical for the IO subsystem. 614 * Please do not alter this order without good reasons and regression 615 * testing. Specifically, as large blocks of memory are subdivided, 616 * the order in which smaller blocks are delivered depends on the order 617 * they're subdivided in this function. This is the primary factor 618 * influencing the order in which pages are delivered to the IO 619 * subsystem according to empirical testing, and this is also justified 620 * by considering the behavior of a buddy system containing a single 621 * large block of memory acted on by a series of small allocations. 622 * This behavior is a critical factor in sglist merging's success. 623 * 624 * -- wli 625 */ 626static inline void expand(struct zone *zone, struct page *page, 627 int low, int high, struct free_area *area, 628 int migratetype) 629{ 630 unsigned long size = 1 << high; 631 632 while (high > low) { 633 area--; 634 high--; 635 size >>= 1; 636 VM_BUG_ON(bad_range(zone, &page[size])); 637 list_add(&page[size].lru, &area->free_list[migratetype]); 638 area->nr_free++; 639 set_page_order(&page[size], high); 640 } 641} 642 643/* 644 * This page is about to be returned from the page allocator 645 */ 646static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) 647{ 648 if (unlikely(page_mapcount(page) | 649 (page->mapping != NULL) | 650 (atomic_read(&page->_count) != 0) | 651 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) { 652 bad_page(page); 653 return 1; 654 } 655 656 set_page_private(page, 0); 657 set_page_refcounted(page); 658 659 arch_alloc_page(page, order); 660 kernel_map_pages(page, 1 << order, 1); 661 662 if (gfp_flags & __GFP_ZERO) 663 prep_zero_page(page, order, gfp_flags); 664 665 if (order && (gfp_flags & __GFP_COMP)) 666 prep_compound_page(page, order); 667 668 return 0; 669} 670 671/* 672 * Go through the free lists for the given migratetype and remove 673 * the smallest available page from the freelists 674 */ 675static inline 676struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, 677 int migratetype) 678{ 679 unsigned int current_order; 680 struct free_area * area; 681 struct page *page; 682 683 /* Find a page of the appropriate size in the preferred list */ 684 for (current_order = order; current_order < MAX_ORDER; ++current_order) { 685 area = &(zone->free_area[current_order]); 686 if (list_empty(&area->free_list[migratetype])) 687 continue; 688 689 page = list_entry(area->free_list[migratetype].next, 690 struct page, lru); 691 list_del(&page->lru); 692 rmv_page_order(page); 693 area->nr_free--; 694 expand(zone, page, order, current_order, area, migratetype); 695 return page; 696 } 697 698 return NULL; 699} 700 701 702/* 703 * This array describes the order lists are fallen back to when 704 * the free lists for the desirable migrate type are depleted 705 */ 706static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = { 707 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, 708 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, 709 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE }, 710 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */ 711}; 712 713/* 714 * Move the free pages in a range to the free lists of the requested type. 715 * Note that start_page and end_pages are not aligned on a pageblock 716 * boundary. If alignment is required, use move_freepages_block() 717 */ 718static int move_freepages(struct zone *zone, 719 struct page *start_page, struct page *end_page, 720 int migratetype) 721{ 722 struct page *page; 723 unsigned long order; 724 int pages_moved = 0; 725 726#ifndef CONFIG_HOLES_IN_ZONE 727 /* 728 * page_zone is not safe to call in this context when 729 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant 730 * anyway as we check zone boundaries in move_freepages_block(). 731 * Remove at a later date when no bug reports exist related to 732 * grouping pages by mobility 733 */ 734 BUG_ON(page_zone(start_page) != page_zone(end_page)); 735#endif 736 737 for (page = start_page; page <= end_page;) { 738 /* Make sure we are not inadvertently changing nodes */ 739 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone)); 740 741 if (!pfn_valid_within(page_to_pfn(page))) { 742 page++; 743 continue; 744 } 745 746 if (!PageBuddy(page)) { 747 page++; 748 continue; 749 } 750 751 order = page_order(page); 752 list_del(&page->lru); 753 list_add(&page->lru, 754 &zone->free_area[order].free_list[migratetype]); 755 page += 1 << order; 756 pages_moved += 1 << order; 757 } 758 759 return pages_moved; 760} 761 762static int move_freepages_block(struct zone *zone, struct page *page, 763 int migratetype) 764{ 765 unsigned long start_pfn, end_pfn; 766 struct page *start_page, *end_page; 767 768 start_pfn = page_to_pfn(page); 769 start_pfn = start_pfn & ~(pageblock_nr_pages-1); 770 start_page = pfn_to_page(start_pfn); 771 end_page = start_page + pageblock_nr_pages - 1; 772 end_pfn = start_pfn + pageblock_nr_pages - 1; 773 774 /* Do not cross zone boundaries */ 775 if (start_pfn < zone->zone_start_pfn) 776 start_page = page; 777 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages) 778 return 0; 779 780 return move_freepages(zone, start_page, end_page, migratetype); 781} 782 783/* Remove an element from the buddy allocator from the fallback list */ 784static inline struct page * 785__rmqueue_fallback(struct zone *zone, int order, int start_migratetype) 786{ 787 struct free_area * area; 788 int current_order; 789 struct page *page; 790 int migratetype, i; 791 792 /* Find the largest possible block of pages in the other list */ 793 for (current_order = MAX_ORDER-1; current_order >= order; 794 --current_order) { 795 for (i = 0; i < MIGRATE_TYPES - 1; i++) { 796 migratetype = fallbacks[start_migratetype][i]; 797 798 /* MIGRATE_RESERVE handled later if necessary */ 799 if (migratetype == MIGRATE_RESERVE) 800 continue; 801 802 area = &(zone->free_area[current_order]); 803 if (list_empty(&area->free_list[migratetype])) 804 continue; 805 806 page = list_entry(area->free_list[migratetype].next, 807 struct page, lru); 808 area->nr_free--; 809 810 /* 811 * If breaking a large block of pages, move all free 812 * pages to the preferred allocation list. If falling 813 * back for a reclaimable kernel allocation, be more 814 * agressive about taking ownership of free pages 815 */ 816 if (unlikely(current_order >= (pageblock_order >> 1)) || 817 start_migratetype == MIGRATE_RECLAIMABLE) { 818 unsigned long pages; 819 pages = move_freepages_block(zone, page, 820 start_migratetype); 821 822 /* Claim the whole block if over half of it is free */ 823 if (pages >= (1 << (pageblock_order-1))) 824 set_pageblock_migratetype(page, 825 start_migratetype); 826 827 migratetype = start_migratetype; 828 } 829 830 /* Remove the page from the freelists */ 831 list_del(&page->lru); 832 rmv_page_order(page); 833 834 if (current_order == pageblock_order) 835 set_pageblock_migratetype(page, 836 start_migratetype); 837 838 expand(zone, page, order, current_order, area, migratetype); 839 return page; 840 } 841 } 842 843 return NULL; 844} 845 846/* 847 * Do the hard work of removing an element from the buddy allocator. 848 * Call me with the zone->lock already held. 849 */ 850static struct page *__rmqueue(struct zone *zone, unsigned int order, 851 int migratetype) 852{ 853 struct page *page; 854 855retry_reserve: 856 page = __rmqueue_smallest(zone, order, migratetype); 857 858 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) { 859 page = __rmqueue_fallback(zone, order, migratetype); 860 861 /* 862 * Use MIGRATE_RESERVE rather than fail an allocation. goto 863 * is used because __rmqueue_smallest is an inline function 864 * and we want just one call site 865 */ 866 if (!page) { 867 migratetype = MIGRATE_RESERVE; 868 goto retry_reserve; 869 } 870 } 871 872 return page; 873} 874 875/* 876 * Obtain a specified number of elements from the buddy allocator, all under 877 * a single hold of the lock, for efficiency. Add them to the supplied list. 878 * Returns the number of new pages which were placed at *list. 879 */ 880static int rmqueue_bulk(struct zone *zone, unsigned int order, 881 unsigned long count, struct list_head *list, 882 int migratetype) 883{ 884 int i; 885 886 spin_lock(&zone->lock); 887 for (i = 0; i < count; ++i) { 888 struct page *page = __rmqueue(zone, order, migratetype); 889 if (unlikely(page == NULL)) 890 break; 891 892 /* 893 * Split buddy pages returned by expand() are received here 894 * in physical page order. The page is added to the callers and 895 * list and the list head then moves forward. From the callers 896 * perspective, the linked list is ordered by page number in 897 * some conditions. This is useful for IO devices that can 898 * merge IO requests if the physical pages are ordered 899 * properly. 900 */ 901 list_add(&page->lru, list); 902 set_page_private(page, migratetype); 903 list = &page->lru; 904 } 905 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); 906 spin_unlock(&zone->lock); 907 return i; 908} 909 910#ifdef CONFIG_NUMA 911/* 912 * Called from the vmstat counter updater to drain pagesets of this 913 * currently executing processor on remote nodes after they have 914 * expired. 915 * 916 * Note that this function must be called with the thread pinned to 917 * a single processor. 918 */ 919void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) 920{ 921 unsigned long flags; 922 int to_drain; 923 924 local_irq_save(flags); 925 if (pcp->count >= pcp->batch) 926 to_drain = pcp->batch; 927 else 928 to_drain = pcp->count; 929 free_pages_bulk(zone, to_drain, &pcp->list, 0); 930 pcp->count -= to_drain; 931 local_irq_restore(flags); 932} 933#endif 934 935/* 936 * Drain pages of the indicated processor. 937 * 938 * The processor must either be the current processor and the 939 * thread pinned to the current processor or a processor that 940 * is not online. 941 */ 942static void drain_pages(unsigned int cpu) 943{ 944 unsigned long flags; 945 struct zone *zone; 946 947 for_each_populated_zone(zone) { 948 struct per_cpu_pageset *pset; 949 struct per_cpu_pages *pcp; 950 951 pset = zone_pcp(zone, cpu); 952 953 pcp = &pset->pcp; 954 local_irq_save(flags); 955 free_pages_bulk(zone, pcp->count, &pcp->list, 0); 956 pcp->count = 0; 957 local_irq_restore(flags); 958 } 959} 960 961/* 962 * Spill all of this CPU's per-cpu pages back into the buddy allocator. 963 */ 964void drain_local_pages(void *arg) 965{ 966 drain_pages(smp_processor_id()); 967} 968 969/* 970 * Spill all the per-cpu pages from all CPUs back into the buddy allocator 971 */ 972void drain_all_pages(void) 973{ 974 on_each_cpu(drain_local_pages, NULL, 1); 975} 976 977#ifdef CONFIG_HIBERNATION 978 979void mark_free_pages(struct zone *zone) 980{ 981 unsigned long pfn, max_zone_pfn; 982 unsigned long flags; 983 int order, t; 984 struct list_head *curr; 985 986 if (!zone->spanned_pages) 987 return; 988 989 spin_lock_irqsave(&zone->lock, flags); 990 991 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; 992 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) 993 if (pfn_valid(pfn)) { 994 struct page *page = pfn_to_page(pfn); 995 996 if (!swsusp_page_is_forbidden(page)) 997 swsusp_unset_page_free(page); 998 } 999 1000 for_each_migratetype_order(order, t) { 1001 list_for_each(curr, &zone->free_area[order].free_list[t]) { 1002 unsigned long i; 1003 1004 pfn = page_to_pfn(list_entry(curr, struct page, lru)); 1005 for (i = 0; i < (1UL << order); i++) 1006 swsusp_set_page_free(pfn_to_page(pfn + i)); 1007 } 1008 } 1009 spin_unlock_irqrestore(&zone->lock, flags); 1010} 1011#endif /* CONFIG_PM */ 1012 1013/* 1014 * Free a 0-order page 1015 */ 1016static void free_hot_cold_page(struct page *page, int cold) 1017{ 1018 struct zone *zone = page_zone(page); 1019 struct per_cpu_pages *pcp; 1020 unsigned long flags; 1021 int clearMlocked = PageMlocked(page); 1022 1023 if (PageAnon(page)) 1024 page->mapping = NULL; 1025 if (free_pages_check(page)) 1026 return; 1027 1028 if (!PageHighMem(page)) { 1029 debug_check_no_locks_freed(page_address(page), PAGE_SIZE); 1030 debug_check_no_obj_freed(page_address(page), PAGE_SIZE); 1031 } 1032 arch_free_page(page, 0); 1033 kernel_map_pages(page, 1, 0); 1034 1035 pcp = &zone_pcp(zone, get_cpu())->pcp; 1036 set_page_private(page, get_pageblock_migratetype(page)); 1037 local_irq_save(flags); 1038 if (unlikely(clearMlocked)) 1039 free_page_mlock(page); 1040 __count_vm_event(PGFREE); 1041 1042 if (cold) 1043 list_add_tail(&page->lru, &pcp->list); 1044 else 1045 list_add(&page->lru, &pcp->list); 1046 pcp->count++; 1047 if (pcp->count >= pcp->high) { 1048 free_pages_bulk(zone, pcp->batch, &pcp->list, 0); 1049 pcp->count -= pcp->batch; 1050 } 1051 local_irq_restore(flags); 1052 put_cpu(); 1053} 1054 1055void free_hot_page(struct page *page) 1056{ 1057 free_hot_cold_page(page, 0); 1058} 1059 1060void free_cold_page(struct page *page) 1061{ 1062 free_hot_cold_page(page, 1); 1063} 1064 1065/* 1066 * split_page takes a non-compound higher-order page, and splits it into 1067 * n (1<<order) sub-pages: page[0..n] 1068 * Each sub-page must be freed individually. 1069 * 1070 * Note: this is probably too low level an operation for use in drivers. 1071 * Please consult with lkml before using this in your driver. 1072 */ 1073void split_page(struct page *page, unsigned int order) 1074{ 1075 int i; 1076 1077 VM_BUG_ON(PageCompound(page)); 1078 VM_BUG_ON(!page_count(page)); 1079 for (i = 1; i < (1 << order); i++) 1080 set_page_refcounted(page + i); 1081} 1082 1083/* 1084 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But 1085 * we cheat by calling it from here, in the order > 0 path. Saves a branch 1086 * or two. 1087 */ 1088static inline 1089struct page *buffered_rmqueue(struct zone *preferred_zone, 1090 struct zone *zone, int order, gfp_t gfp_flags, 1091 int migratetype) 1092{ 1093 unsigned long flags; 1094 struct page *page; 1095 int cold = !!(gfp_flags & __GFP_COLD); 1096 int cpu; 1097 1098again: 1099 cpu = get_cpu(); 1100 if (likely(order == 0)) { 1101 struct per_cpu_pages *pcp; 1102 1103 pcp = &zone_pcp(zone, cpu)->pcp; 1104 local_irq_save(flags); 1105 if (!pcp->count) { 1106 pcp->count = rmqueue_bulk(zone, 0, 1107 pcp->batch, &pcp->list, migratetype); 1108 if (unlikely(!pcp->count)) 1109 goto failed; 1110 } 1111 1112 /* Find a page of the appropriate migrate type */ 1113 if (cold) { 1114 list_for_each_entry_reverse(page, &pcp->list, lru) 1115 if (page_private(page) == migratetype) 1116 break; 1117 } else { 1118 list_for_each_entry(page, &pcp->list, lru) 1119 if (page_private(page) == migratetype) 1120 break; 1121 } 1122 1123 /* Allocate more to the pcp list if necessary */ 1124 if (unlikely(&page->lru == &pcp->list)) { 1125 pcp->count += rmqueue_bulk(zone, 0, 1126 pcp->batch, &pcp->list, migratetype); 1127 page = list_entry(pcp->list.next, struct page, lru); 1128 } 1129 1130 list_del(&page->lru); 1131 pcp->count--; 1132 } else { 1133 if (unlikely(gfp_flags & __GFP_NOFAIL)) { 1134 /* 1135 * __GFP_NOFAIL is not to be used in new code. 1136 * 1137 * All __GFP_NOFAIL callers should be fixed so that they 1138 * properly detect and handle allocation failures. 1139 * 1140 * We most definitely don't want callers attempting to 1141 * allocate greater than single-page units with 1142 * __GFP_NOFAIL. 1143 */ 1144 WARN_ON_ONCE(order > 0); 1145 } 1146 spin_lock_irqsave(&zone->lock, flags); 1147 page = __rmqueue(zone, order, migratetype); 1148 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order)); 1149 spin_unlock(&zone->lock); 1150 if (!page) 1151 goto failed; 1152 } 1153 1154 __count_zone_vm_events(PGALLOC, zone, 1 << order); 1155 zone_statistics(preferred_zone, zone); 1156 local_irq_restore(flags); 1157 put_cpu(); 1158 1159 VM_BUG_ON(bad_range(zone, page)); 1160 if (prep_new_page(page, order, gfp_flags)) 1161 goto again; 1162 return page; 1163 1164failed: 1165 local_irq_restore(flags); 1166 put_cpu(); 1167 return NULL; 1168} 1169 1170/* The ALLOC_WMARK bits are used as an index to zone->watermark */ 1171#define ALLOC_WMARK_MIN WMARK_MIN 1172#define ALLOC_WMARK_LOW WMARK_LOW 1173#define ALLOC_WMARK_HIGH WMARK_HIGH 1174#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 1175 1176/* Mask to get the watermark bits */ 1177#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 1178 1179#define ALLOC_HARDER 0x10 /* try to alloc harder */ 1180#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ 1181#define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 1182 1183#ifdef CONFIG_FAIL_PAGE_ALLOC 1184 1185static struct fail_page_alloc_attr { 1186 struct fault_attr attr; 1187 1188 u32 ignore_gfp_highmem; 1189 u32 ignore_gfp_wait; 1190 u32 min_order; 1191 1192#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS 1193 1194 struct dentry *ignore_gfp_highmem_file; 1195 struct dentry *ignore_gfp_wait_file; 1196 struct dentry *min_order_file; 1197 1198#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ 1199 1200} fail_page_alloc = { 1201 .attr = FAULT_ATTR_INITIALIZER, 1202 .ignore_gfp_wait = 1, 1203 .ignore_gfp_highmem = 1, 1204 .min_order = 1, 1205}; 1206 1207static int __init setup_fail_page_alloc(char *str) 1208{ 1209 return setup_fault_attr(&fail_page_alloc.attr, str); 1210} 1211__setup("fail_page_alloc=", setup_fail_page_alloc); 1212 1213static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) 1214{ 1215 if (order < fail_page_alloc.min_order) 1216 return 0; 1217 if (gfp_mask & __GFP_NOFAIL) 1218 return 0; 1219 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) 1220 return 0; 1221 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT)) 1222 return 0; 1223 1224 return should_fail(&fail_page_alloc.attr, 1 << order); 1225} 1226 1227#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS 1228 1229static int __init fail_page_alloc_debugfs(void) 1230{ 1231 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR; 1232 struct dentry *dir; 1233 int err; 1234 1235 err = init_fault_attr_dentries(&fail_page_alloc.attr, 1236 "fail_page_alloc"); 1237 if (err) 1238 return err; 1239 dir = fail_page_alloc.attr.dentries.dir; 1240 1241 fail_page_alloc.ignore_gfp_wait_file = 1242 debugfs_create_bool("ignore-gfp-wait", mode, dir, 1243 &fail_page_alloc.ignore_gfp_wait); 1244 1245 fail_page_alloc.ignore_gfp_highmem_file = 1246 debugfs_create_bool("ignore-gfp-highmem", mode, dir, 1247 &fail_page_alloc.ignore_gfp_highmem); 1248 fail_page_alloc.min_order_file = 1249 debugfs_create_u32("min-order", mode, dir, 1250 &fail_page_alloc.min_order); 1251 1252 if (!fail_page_alloc.ignore_gfp_wait_file || 1253 !fail_page_alloc.ignore_gfp_highmem_file || 1254 !fail_page_alloc.min_order_file) { 1255 err = -ENOMEM; 1256 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file); 1257 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file); 1258 debugfs_remove(fail_page_alloc.min_order_file); 1259 cleanup_fault_attr_dentries(&fail_page_alloc.attr); 1260 } 1261 1262 return err; 1263} 1264 1265late_initcall(fail_page_alloc_debugfs); 1266 1267#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ 1268 1269#else /* CONFIG_FAIL_PAGE_ALLOC */ 1270 1271static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) 1272{ 1273 return 0; 1274} 1275 1276#endif /* CONFIG_FAIL_PAGE_ALLOC */ 1277 1278/* 1279 * Return 1 if free pages are above 'mark'. This takes into account the order 1280 * of the allocation. 1281 */ 1282int zone_watermark_ok(struct zone *z, int order, unsigned long mark, 1283 int classzone_idx, int alloc_flags) 1284{ 1285 /* free_pages my go negative - that's OK */ 1286 long min = mark; 1287 long free_pages = zone_page_state(z, NR_FREE_PAGES) - (1 << order) + 1; 1288 int o; 1289 1290 if (alloc_flags & ALLOC_HIGH) 1291 min -= min / 2; 1292 if (alloc_flags & ALLOC_HARDER) 1293 min -= min / 4; 1294 1295 if (free_pages <= min + z->lowmem_reserve[classzone_idx]) 1296 return 0; 1297 for (o = 0; o < order; o++) { 1298 /* At the next order, this order's pages become unavailable */ 1299 free_pages -= z->free_area[o].nr_free << o; 1300 1301 /* Require fewer higher order pages to be free */ 1302 min >>= 1; 1303 1304 if (free_pages <= min) 1305 return 0; 1306 } 1307 return 1; 1308} 1309 1310#ifdef CONFIG_NUMA 1311/* 1312 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to 1313 * skip over zones that are not allowed by the cpuset, or that have 1314 * been recently (in last second) found to be nearly full. See further 1315 * comments in mmzone.h. Reduces cache footprint of zonelist scans 1316 * that have to skip over a lot of full or unallowed zones. 1317 * 1318 * If the zonelist cache is present in the passed in zonelist, then 1319 * returns a pointer to the allowed node mask (either the current 1320 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].) 1321 * 1322 * If the zonelist cache is not available for this zonelist, does 1323 * nothing and returns NULL. 1324 * 1325 * If the fullzones BITMAP in the zonelist cache is stale (more than 1326 * a second since last zap'd) then we zap it out (clear its bits.) 1327 * 1328 * We hold off even calling zlc_setup, until after we've checked the 1329 * first zone in the zonelist, on the theory that most allocations will 1330 * be satisfied from that first zone, so best to examine that zone as 1331 * quickly as we can. 1332 */ 1333static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) 1334{ 1335 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1336 nodemask_t *allowednodes; /* zonelist_cache approximation */ 1337 1338 zlc = zonelist->zlcache_ptr; 1339 if (!zlc) 1340 return NULL; 1341 1342 if (time_after(jiffies, zlc->last_full_zap + HZ)) { 1343 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); 1344 zlc->last_full_zap = jiffies; 1345 } 1346 1347 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ? 1348 &cpuset_current_mems_allowed : 1349 &node_states[N_HIGH_MEMORY]; 1350 return allowednodes; 1351} 1352 1353/* 1354 * Given 'z' scanning a zonelist, run a couple of quick checks to see 1355 * if it is worth looking at further for free memory: 1356 * 1) Check that the zone isn't thought to be full (doesn't have its 1357 * bit set in the zonelist_cache fullzones BITMAP). 1358 * 2) Check that the zones node (obtained from the zonelist_cache 1359 * z_to_n[] mapping) is allowed in the passed in allowednodes mask. 1360 * Return true (non-zero) if zone is worth looking at further, or 1361 * else return false (zero) if it is not. 1362 * 1363 * This check -ignores- the distinction between various watermarks, 1364 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is 1365 * found to be full for any variation of these watermarks, it will 1366 * be considered full for up to one second by all requests, unless 1367 * we are so low on memory on all allowed nodes that we are forced 1368 * into the second scan of the zonelist. 1369 * 1370 * In the second scan we ignore this zonelist cache and exactly 1371 * apply the watermarks to all zones, even it is slower to do so. 1372 * We are low on memory in the second scan, and should leave no stone 1373 * unturned looking for a free page. 1374 */ 1375static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, 1376 nodemask_t *allowednodes) 1377{ 1378 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1379 int i; /* index of *z in zonelist zones */ 1380 int n; /* node that zone *z is on */ 1381 1382 zlc = zonelist->zlcache_ptr; 1383 if (!zlc) 1384 return 1; 1385 1386 i = z - zonelist->_zonerefs; 1387 n = zlc->z_to_n[i]; 1388 1389 /* This zone is worth trying if it is allowed but not full */ 1390 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones); 1391} 1392 1393/* 1394 * Given 'z' scanning a zonelist, set the corresponding bit in 1395 * zlc->fullzones, so that subsequent attempts to allocate a page 1396 * from that zone don't waste time re-examining it. 1397 */ 1398static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) 1399{ 1400 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1401 int i; /* index of *z in zonelist zones */ 1402 1403 zlc = zonelist->zlcache_ptr; 1404 if (!zlc) 1405 return; 1406 1407 i = z - zonelist->_zonerefs; 1408 1409 set_bit(i, zlc->fullzones); 1410} 1411 1412#else /* CONFIG_NUMA */ 1413 1414static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) 1415{ 1416 return NULL; 1417} 1418 1419static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, 1420 nodemask_t *allowednodes) 1421{ 1422 return 1; 1423} 1424 1425static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) 1426{ 1427} 1428#endif /* CONFIG_NUMA */ 1429 1430/* 1431 * get_page_from_freelist goes through the zonelist trying to allocate 1432 * a page. 1433 */ 1434static struct page * 1435get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order, 1436 struct zonelist *zonelist, int high_zoneidx, int alloc_flags, 1437 struct zone *preferred_zone, int migratetype) 1438{ 1439 struct zoneref *z; 1440 struct page *page = NULL; 1441 int classzone_idx; 1442 struct zone *zone; 1443 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */ 1444 int zlc_active = 0; /* set if using zonelist_cache */ 1445 int did_zlc_setup = 0; /* just call zlc_setup() one time */ 1446 1447 classzone_idx = zone_idx(preferred_zone); 1448zonelist_scan: 1449 /* 1450 * Scan zonelist, looking for a zone with enough free. 1451 * See also cpuset_zone_allowed() comment in kernel/cpuset.c. 1452 */ 1453 for_each_zone_zonelist_nodemask(zone, z, zonelist, 1454 high_zoneidx, nodemask) { 1455 if (NUMA_BUILD && zlc_active && 1456 !zlc_zone_worth_trying(zonelist, z, allowednodes)) 1457 continue; 1458 if ((alloc_flags & ALLOC_CPUSET) && 1459 !cpuset_zone_allowed_softwall(zone, gfp_mask)) 1460 goto try_next_zone; 1461 1462 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); 1463 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) { 1464 unsigned long mark; 1465 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; 1466 if (!zone_watermark_ok(zone, order, mark, 1467 classzone_idx, alloc_flags)) { 1468 if (!zone_reclaim_mode || 1469 !zone_reclaim(zone, gfp_mask, order)) 1470 goto this_zone_full; 1471 } 1472 } 1473 1474 page = buffered_rmqueue(preferred_zone, zone, order, 1475 gfp_mask, migratetype); 1476 if (page) 1477 break; 1478this_zone_full: 1479 if (NUMA_BUILD) 1480 zlc_mark_zone_full(zonelist, z); 1481try_next_zone: 1482 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) { 1483 /* 1484 * we do zlc_setup after the first zone is tried but only 1485 * if there are multiple nodes make it worthwhile 1486 */ 1487 allowednodes = zlc_setup(zonelist, alloc_flags); 1488 zlc_active = 1; 1489 did_zlc_setup = 1; 1490 } 1491 } 1492 1493 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) { 1494 /* Disable zlc cache for second zonelist scan */ 1495 zlc_active = 0; 1496 goto zonelist_scan; 1497 } 1498 return page; 1499} 1500 1501static inline int 1502should_alloc_retry(gfp_t gfp_mask, unsigned int order, 1503 unsigned long pages_reclaimed) 1504{ 1505 /* Do not loop if specifically requested */ 1506 if (gfp_mask & __GFP_NORETRY) 1507 return 0; 1508 1509 /* 1510 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER 1511 * means __GFP_NOFAIL, but that may not be true in other 1512 * implementations. 1513 */ 1514 if (order <= PAGE_ALLOC_COSTLY_ORDER) 1515 return 1; 1516 1517 /* 1518 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is 1519 * specified, then we retry until we no longer reclaim any pages 1520 * (above), or we've reclaimed an order of pages at least as 1521 * large as the allocation's order. In both cases, if the 1522 * allocation still fails, we stop retrying. 1523 */ 1524 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order)) 1525 return 1; 1526 1527 /* 1528 * Don't let big-order allocations loop unless the caller 1529 * explicitly requests that. 1530 */ 1531 if (gfp_mask & __GFP_NOFAIL) 1532 return 1; 1533 1534 return 0; 1535} 1536 1537static inline struct page * 1538__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, 1539 struct zonelist *zonelist, enum zone_type high_zoneidx, 1540 nodemask_t *nodemask, struct zone *preferred_zone, 1541 int migratetype) 1542{ 1543 struct page *page; 1544 1545 /* Acquire the OOM killer lock for the zones in zonelist */ 1546 if (!try_set_zone_oom(zonelist, gfp_mask)) { 1547 schedule_timeout_uninterruptible(1); 1548 return NULL; 1549 } 1550 1551 /* 1552 * Go through the zonelist yet one more time, keep very high watermark 1553 * here, this is only to catch a parallel oom killing, we must fail if 1554 * we're still under heavy pressure. 1555 */ 1556 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, 1557 order, zonelist, high_zoneidx, 1558 ALLOC_WMARK_HIGH|ALLOC_CPUSET, 1559 preferred_zone, migratetype); 1560 if (page) 1561 goto out; 1562 1563 /* The OOM killer will not help higher order allocs */ 1564 if (order > PAGE_ALLOC_COSTLY_ORDER) 1565 goto out; 1566 1567 /* Exhausted what can be done so it's blamo time */ 1568 out_of_memory(zonelist, gfp_mask, order); 1569 1570out: 1571 clear_zonelist_oom(zonelist, gfp_mask); 1572 return page; 1573} 1574 1575/* The really slow allocator path where we enter direct reclaim */ 1576static inline struct page * 1577__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, 1578 struct zonelist *zonelist, enum zone_type high_zoneidx, 1579 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, 1580 int migratetype, unsigned long *did_some_progress) 1581{ 1582 struct page *page = NULL; 1583 struct reclaim_state reclaim_state; 1584 struct task_struct *p = current; 1585 1586 cond_resched(); 1587 1588 /* We now go into synchronous reclaim */ 1589 cpuset_memory_pressure_bump(); 1590 1591 /* 1592 * The task's cpuset might have expanded its set of allowable nodes 1593 */ 1594 p->flags |= PF_MEMALLOC; 1595 lockdep_set_current_reclaim_state(gfp_mask); 1596 reclaim_state.reclaimed_slab = 0; 1597 p->reclaim_state = &reclaim_state; 1598 1599 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask); 1600 1601 p->reclaim_state = NULL; 1602 lockdep_clear_current_reclaim_state(); 1603 p->flags &= ~PF_MEMALLOC; 1604 1605 cond_resched(); 1606 1607 if (order != 0) 1608 drain_all_pages(); 1609 1610 if (likely(*did_some_progress)) 1611 page = get_page_from_freelist(gfp_mask, nodemask, order, 1612 zonelist, high_zoneidx, 1613 alloc_flags, preferred_zone, 1614 migratetype); 1615 return page; 1616} 1617 1618/* 1619 * This is called in the allocator slow-path if the allocation request is of 1620 * sufficient urgency to ignore watermarks and take other desperate measures 1621 */ 1622static inline struct page * 1623__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order, 1624 struct zonelist *zonelist, enum zone_type high_zoneidx, 1625 nodemask_t *nodemask, struct zone *preferred_zone, 1626 int migratetype) 1627{ 1628 struct page *page; 1629 1630 do { 1631 page = get_page_from_freelist(gfp_mask, nodemask, order, 1632 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS, 1633 preferred_zone, migratetype); 1634 1635 if (!page && gfp_mask & __GFP_NOFAIL) 1636 congestion_wait(WRITE, HZ/50); 1637 } while (!page && (gfp_mask & __GFP_NOFAIL)); 1638 1639 return page; 1640} 1641 1642static inline 1643void wake_all_kswapd(unsigned int order, struct zonelist *zonelist, 1644 enum zone_type high_zoneidx) 1645{ 1646 struct zoneref *z; 1647 struct zone *zone; 1648 1649 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) 1650 wakeup_kswapd(zone, order); 1651} 1652 1653static inline int 1654gfp_to_alloc_flags(gfp_t gfp_mask) 1655{ 1656 struct task_struct *p = current; 1657 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; 1658 const gfp_t wait = gfp_mask & __GFP_WAIT; 1659 1660 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ 1661 BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH); 1662 1663 /* 1664 * The caller may dip into page reserves a bit more if the caller 1665 * cannot run direct reclaim, or if the caller has realtime scheduling 1666 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will 1667 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). 1668 */ 1669 alloc_flags |= (gfp_mask & __GFP_HIGH); 1670 1671 if (!wait) { 1672 alloc_flags |= ALLOC_HARDER; 1673 /* 1674 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. 1675 * See also cpuset_zone_allowed() comment in kernel/cpuset.c. 1676 */ 1677 alloc_flags &= ~ALLOC_CPUSET; 1678 } else if (unlikely(rt_task(p))) 1679 alloc_flags |= ALLOC_HARDER; 1680 1681 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { 1682 if (!in_interrupt() && 1683 ((p->flags & PF_MEMALLOC) || 1684 unlikely(test_thread_flag(TIF_MEMDIE)))) 1685 alloc_flags |= ALLOC_NO_WATERMARKS; 1686 } 1687 1688 return alloc_flags; 1689} 1690 1691static inline struct page * 1692__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, 1693 struct zonelist *zonelist, enum zone_type high_zoneidx, 1694 nodemask_t *nodemask, struct zone *preferred_zone, 1695 int migratetype) 1696{ 1697 const gfp_t wait = gfp_mask & __GFP_WAIT; 1698 struct page *page = NULL; 1699 int alloc_flags; 1700 unsigned long pages_reclaimed = 0; 1701 unsigned long did_some_progress; 1702 struct task_struct *p = current; 1703 1704 /* 1705 * In the slowpath, we sanity check order to avoid ever trying to 1706 * reclaim >= MAX_ORDER areas which will never succeed. Callers may 1707 * be using allocators in order of preference for an area that is 1708 * too large. 1709 */ 1710 if (WARN_ON_ONCE(order >= MAX_ORDER)) 1711 return NULL; 1712 1713 /* 1714 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and 1715 * __GFP_NOWARN set) should not cause reclaim since the subsystem 1716 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim 1717 * using a larger set of nodes after it has established that the 1718 * allowed per node queues are empty and that nodes are 1719 * over allocated. 1720 */ 1721 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE) 1722 goto nopage; 1723 1724 wake_all_kswapd(order, zonelist, high_zoneidx); 1725 1726 /* 1727 * OK, we're below the kswapd watermark and have kicked background 1728 * reclaim. Now things get more complex, so set up alloc_flags according 1729 * to how we want to proceed. 1730 */ 1731 alloc_flags = gfp_to_alloc_flags(gfp_mask); 1732 1733restart: 1734 /* This is the last chance, in general, before the goto nopage. */ 1735 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, 1736 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, 1737 preferred_zone, migratetype); 1738 if (page) 1739 goto got_pg; 1740 1741rebalance: 1742 /* Allocate without watermarks if the context allows */ 1743 if (alloc_flags & ALLOC_NO_WATERMARKS) { 1744 page = __alloc_pages_high_priority(gfp_mask, order, 1745 zonelist, high_zoneidx, nodemask, 1746 preferred_zone, migratetype); 1747 if (page) 1748 goto got_pg; 1749 } 1750 1751 /* Atomic allocations - we can't balance anything */ 1752 if (!wait) 1753 goto nopage; 1754 1755 /* Avoid recursion of direct reclaim */ 1756 if (p->flags & PF_MEMALLOC) 1757 goto nopage; 1758 1759 /* Try direct reclaim and then allocating */ 1760 page = __alloc_pages_direct_reclaim(gfp_mask, order, 1761 zonelist, high_zoneidx, 1762 nodemask, 1763 alloc_flags, preferred_zone, 1764 migratetype, &did_some_progress); 1765 if (page) 1766 goto got_pg; 1767 1768 /* 1769 * If we failed to make any progress reclaiming, then we are 1770 * running out of options and have to consider going OOM 1771 */ 1772 if (!did_some_progress) { 1773 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { 1774 if (oom_killer_disabled) 1775 goto nopage; 1776 page = __alloc_pages_may_oom(gfp_mask, order, 1777 zonelist, high_zoneidx, 1778 nodemask, preferred_zone, 1779 migratetype); 1780 if (page) 1781 goto got_pg; 1782 1783 /* 1784 * The OOM killer does not trigger for high-order allocations 1785 * but if no progress is being made, there are no other 1786 * options and retrying is unlikely to help 1787 */ 1788 if (order > PAGE_ALLOC_COSTLY_ORDER) 1789 goto nopage; 1790 1791 goto restart; 1792 } 1793 } 1794 1795 /* Check if we should retry the allocation */ 1796 pages_reclaimed += did_some_progress; 1797 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) { 1798 /* Wait for some write requests to complete then retry */ 1799 congestion_wait(WRITE, HZ/50); 1800 goto rebalance; 1801 } 1802 1803nopage: 1804 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) { 1805 printk(KERN_WARNING "%s: page allocation failure." 1806 " order:%d, mode:0x%x\n", 1807 p->comm, order, gfp_mask); 1808 dump_stack(); 1809 show_mem(); 1810 } 1811got_pg: 1812 return page; 1813 1814} 1815 1816/* 1817 * This is the 'heart' of the zoned buddy allocator. 1818 */ 1819struct page * 1820__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, 1821 struct zonelist *zonelist, nodemask_t *nodemask) 1822{ 1823 enum zone_type high_zoneidx = gfp_zone(gfp_mask); 1824 struct zone *preferred_zone; 1825 struct page *page; 1826 int migratetype = allocflags_to_migratetype(gfp_mask); 1827 1828 lockdep_trace_alloc(gfp_mask); 1829 1830 might_sleep_if(gfp_mask & __GFP_WAIT); 1831 1832 if (should_fail_alloc_page(gfp_mask, order)) 1833 return NULL; 1834 1835 /* 1836 * Check the zones suitable for the gfp_mask contain at least one 1837 * valid zone. It's possible to have an empty zonelist as a result 1838 * of GFP_THISNODE and a memoryless node 1839 */ 1840 if (unlikely(!zonelist->_zonerefs->zone)) 1841 return NULL; 1842 1843 /* The preferred zone is used for statistics later */ 1844 first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone); 1845 if (!preferred_zone) 1846 return NULL; 1847 1848 /* First allocation attempt */ 1849 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, 1850 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET, 1851 preferred_zone, migratetype); 1852 if (unlikely(!page)) 1853 page = __alloc_pages_slowpath(gfp_mask, order, 1854 zonelist, high_zoneidx, nodemask, 1855 preferred_zone, migratetype); 1856 1857 return page; 1858} 1859EXPORT_SYMBOL(__alloc_pages_nodemask); 1860 1861/* 1862 * Common helper functions. 1863 */ 1864unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) 1865{ 1866 struct page * page; 1867 page = alloc_pages(gfp_mask, order); 1868 if (!page) 1869 return 0; 1870 return (unsigned long) page_address(page); 1871} 1872 1873EXPORT_SYMBOL(__get_free_pages); 1874 1875unsigned long get_zeroed_page(gfp_t gfp_mask) 1876{ 1877 struct page * page; 1878 1879 /* 1880 * get_zeroed_page() returns a 32-bit address, which cannot represent 1881 * a highmem page 1882 */ 1883 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0); 1884 1885 page = alloc_pages(gfp_mask | __GFP_ZERO, 0); 1886 if (page) 1887 return (unsigned long) page_address(page); 1888 return 0; 1889} 1890 1891EXPORT_SYMBOL(get_zeroed_page); 1892 1893void __pagevec_free(struct pagevec *pvec) 1894{ 1895 int i = pagevec_count(pvec); 1896 1897 while (--i >= 0) 1898 free_hot_cold_page(pvec->pages[i], pvec->cold); 1899} 1900 1901void __free_pages(struct page *page, unsigned int order) 1902{ 1903 if (put_page_testzero(page)) { 1904 if (order == 0) 1905 free_hot_page(page); 1906 else 1907 __free_pages_ok(page, order); 1908 } 1909} 1910 1911EXPORT_SYMBOL(__free_pages); 1912 1913void free_pages(unsigned long addr, unsigned int order) 1914{ 1915 if (addr != 0) { 1916 VM_BUG_ON(!virt_addr_valid((void *)addr)); 1917 __free_pages(virt_to_page((void *)addr), order); 1918 } 1919} 1920 1921EXPORT_SYMBOL(free_pages); 1922 1923/** 1924 * alloc_pages_exact - allocate an exact number physically-contiguous pages. 1925 * @size: the number of bytes to allocate 1926 * @gfp_mask: GFP flags for the allocation 1927 * 1928 * This function is similar to alloc_pages(), except that it allocates the 1929 * minimum number of pages to satisfy the request. alloc_pages() can only 1930 * allocate memory in power-of-two pages. 1931 * 1932 * This function is also limited by MAX_ORDER. 1933 * 1934 * Memory allocated by this function must be released by free_pages_exact(). 1935 */ 1936void *alloc_pages_exact(size_t size, gfp_t gfp_mask) 1937{ 1938 unsigned int order = get_order(size); 1939 unsigned long addr; 1940 1941 addr = __get_free_pages(gfp_mask, order); 1942 if (addr) { 1943 unsigned long alloc_end = addr + (PAGE_SIZE << order); 1944 unsigned long used = addr + PAGE_ALIGN(size); 1945 1946 split_page(virt_to_page(addr), order); 1947 while (used < alloc_end) { 1948 free_page(used); 1949 used += PAGE_SIZE; 1950 } 1951 } 1952 1953 return (void *)addr; 1954} 1955EXPORT_SYMBOL(alloc_pages_exact); 1956 1957/** 1958 * free_pages_exact - release memory allocated via alloc_pages_exact() 1959 * @virt: the value returned by alloc_pages_exact. 1960 * @size: size of allocation, same value as passed to alloc_pages_exact(). 1961 * 1962 * Release the memory allocated by a previous call to alloc_pages_exact. 1963 */ 1964void free_pages_exact(void *virt, size_t size) 1965{ 1966 unsigned long addr = (unsigned long)virt; 1967 unsigned long end = addr + PAGE_ALIGN(size); 1968 1969 while (addr < end) { 1970 free_page(addr); 1971 addr += PAGE_SIZE; 1972 } 1973} 1974EXPORT_SYMBOL(free_pages_exact); 1975 1976static unsigned int nr_free_zone_pages(int offset) 1977{ 1978 struct zoneref *z; 1979 struct zone *zone; 1980 1981 /* Just pick one node, since fallback list is circular */ 1982 unsigned int sum = 0; 1983 1984 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL); 1985 1986 for_each_zone_zonelist(zone, z, zonelist, offset) { 1987 unsigned long size = zone->present_pages; 1988 unsigned long high = high_wmark_pages(zone); 1989 if (size > high) 1990 sum += size - high; 1991 } 1992 1993 return sum; 1994} 1995 1996/* 1997 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL 1998 */ 1999unsigned int nr_free_buffer_pages(void) 2000{ 2001 return nr_free_zone_pages(gfp_zone(GFP_USER)); 2002} 2003EXPORT_SYMBOL_GPL(nr_free_buffer_pages); 2004 2005/* 2006 * Amount of free RAM allocatable within all zones 2007 */ 2008unsigned int nr_free_pagecache_pages(void) 2009{ 2010 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); 2011} 2012 2013static inline void show_node(struct zone *zone) 2014{ 2015 if (NUMA_BUILD) 2016 printk("Node %d ", zone_to_nid(zone)); 2017} 2018 2019void si_meminfo(struct sysinfo *val) 2020{ 2021 val->totalram = totalram_pages; 2022 val->sharedram = 0; 2023 val->freeram = global_page_state(NR_FREE_PAGES); 2024 val->bufferram = nr_blockdev_pages(); 2025 val->totalhigh = totalhigh_pages; 2026 val->freehigh = nr_free_highpages(); 2027 val->mem_unit = PAGE_SIZE; 2028} 2029 2030EXPORT_SYMBOL(si_meminfo); 2031 2032#ifdef CONFIG_NUMA 2033void si_meminfo_node(struct sysinfo *val, int nid) 2034{ 2035 pg_data_t *pgdat = NODE_DATA(nid); 2036 2037 val->totalram = pgdat->node_present_pages; 2038 val->freeram = node_page_state(nid, NR_FREE_PAGES); 2039#ifdef CONFIG_HIGHMEM 2040 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages; 2041 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM], 2042 NR_FREE_PAGES); 2043#else 2044 val->totalhigh = 0; 2045 val->freehigh = 0; 2046#endif 2047 val->mem_unit = PAGE_SIZE; 2048} 2049#endif 2050 2051#define K(x) ((x) << (PAGE_SHIFT-10)) 2052 2053/* 2054 * Show free area list (used inside shift_scroll-lock stuff) 2055 * We also calculate the percentage fragmentation. We do this by counting the 2056 * memory on each free list with the exception of the first item on the list. 2057 */ 2058void show_free_areas(void) 2059{ 2060 int cpu; 2061 struct zone *zone; 2062 2063 for_each_populated_zone(zone) { 2064 show_node(zone); 2065 printk("%s per-cpu:\n", zone->name); 2066 2067 for_each_online_cpu(cpu) { 2068 struct per_cpu_pageset *pageset; 2069 2070 pageset = zone_pcp(zone, cpu); 2071 2072 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n", 2073 cpu, pageset->pcp.high, 2074 pageset->pcp.batch, pageset->pcp.count); 2075 } 2076 } 2077 2078 printk("Active_anon:%lu active_file:%lu inactive_anon:%lu\n" 2079 " inactive_file:%lu" 2080//TODO: check/adjust line lengths 2081#ifdef CONFIG_UNEVICTABLE_LRU 2082 " unevictable:%lu" 2083#endif 2084 " dirty:%lu writeback:%lu unstable:%lu\n" 2085 " free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n", 2086 global_page_state(NR_ACTIVE_ANON), 2087 global_page_state(NR_ACTIVE_FILE), 2088 global_page_state(NR_INACTIVE_ANON), 2089 global_page_state(NR_INACTIVE_FILE), 2090#ifdef CONFIG_UNEVICTABLE_LRU 2091 global_page_state(NR_UNEVICTABLE), 2092#endif 2093 global_page_state(NR_FILE_DIRTY), 2094 global_page_state(NR_WRITEBACK), 2095 global_page_state(NR_UNSTABLE_NFS), 2096 global_page_state(NR_FREE_PAGES), 2097 global_page_state(NR_SLAB_RECLAIMABLE) + 2098 global_page_state(NR_SLAB_UNRECLAIMABLE), 2099 global_page_state(NR_FILE_MAPPED), 2100 global_page_state(NR_PAGETABLE), 2101 global_page_state(NR_BOUNCE)); 2102 2103 for_each_populated_zone(zone) { 2104 int i; 2105 2106 show_node(zone); 2107 printk("%s" 2108 " free:%lukB" 2109 " min:%lukB" 2110 " low:%lukB" 2111 " high:%lukB" 2112 " active_anon:%lukB" 2113 " inactive_anon:%lukB" 2114 " active_file:%lukB" 2115 " inactive_file:%lukB" 2116#ifdef CONFIG_UNEVICTABLE_LRU 2117 " unevictable:%lukB" 2118#endif 2119 " present:%lukB" 2120 " pages_scanned:%lu" 2121 " all_unreclaimable? %s" 2122 "\n", 2123 zone->name, 2124 K(zone_page_state(zone, NR_FREE_PAGES)), 2125 K(min_wmark_pages(zone)), 2126 K(low_wmark_pages(zone)), 2127 K(high_wmark_pages(zone)), 2128 K(zone_page_state(zone, NR_ACTIVE_ANON)), 2129 K(zone_page_state(zone, NR_INACTIVE_ANON)), 2130 K(zone_page_state(zone, NR_ACTIVE_FILE)), 2131 K(zone_page_state(zone, NR_INACTIVE_FILE)), 2132#ifdef CONFIG_UNEVICTABLE_LRU 2133 K(zone_page_state(zone, NR_UNEVICTABLE)), 2134#endif 2135 K(zone->present_pages), 2136 zone->pages_scanned, 2137 (zone_is_all_unreclaimable(zone) ? "yes" : "no") 2138 ); 2139 printk("lowmem_reserve[]:"); 2140 for (i = 0; i < MAX_NR_ZONES; i++) 2141 printk(" %lu", zone->lowmem_reserve[i]); 2142 printk("\n"); 2143 } 2144 2145 for_each_populated_zone(zone) { 2146 unsigned long nr[MAX_ORDER], flags, order, total = 0; 2147 2148 show_node(zone); 2149 printk("%s: ", zone->name); 2150 2151 spin_lock_irqsave(&zone->lock, flags); 2152 for (order = 0; order < MAX_ORDER; order++) { 2153 nr[order] = zone->free_area[order].nr_free; 2154 total += nr[order] << order; 2155 } 2156 spin_unlock_irqrestore(&zone->lock, flags); 2157 for (order = 0; order < MAX_ORDER; order++) 2158 printk("%lu*%lukB ", nr[order], K(1UL) << order); 2159 printk("= %lukB\n", K(total)); 2160 } 2161 2162 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES)); 2163 2164 show_swap_cache_info(); 2165} 2166 2167static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) 2168{ 2169 zoneref->zone = zone; 2170 zoneref->zone_idx = zone_idx(zone); 2171} 2172 2173/* 2174 * Builds allocation fallback zone lists. 2175 * 2176 * Add all populated zones of a node to the zonelist. 2177 */ 2178static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, 2179 int nr_zones, enum zone_type zone_type) 2180{ 2181 struct zone *zone; 2182 2183 BUG_ON(zone_type >= MAX_NR_ZONES); 2184 zone_type++; 2185 2186 do { 2187 zone_type--; 2188 zone = pgdat->node_zones + zone_type; 2189 if (populated_zone(zone)) { 2190 zoneref_set_zone(zone, 2191 &zonelist->_zonerefs[nr_zones++]); 2192 check_highest_zone(zone_type); 2193 } 2194 2195 } while (zone_type); 2196 return nr_zones; 2197} 2198 2199 2200/* 2201 * zonelist_order: 2202 * 0 = automatic detection of better ordering. 2203 * 1 = order by ([node] distance, -zonetype) 2204 * 2 = order by (-zonetype, [node] distance) 2205 * 2206 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create 2207 * the same zonelist. So only NUMA can configure this param. 2208 */ 2209#define ZONELIST_ORDER_DEFAULT 0 2210#define ZONELIST_ORDER_NODE 1 2211#define ZONELIST_ORDER_ZONE 2 2212 2213/* zonelist order in the kernel. 2214 * set_zonelist_order() will set this to NODE or ZONE. 2215 */ 2216static int current_zonelist_order = ZONELIST_ORDER_DEFAULT; 2217static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"}; 2218 2219 2220#ifdef CONFIG_NUMA 2221/* The value user specified ....changed by config */ 2222static int user_zonelist_order = ZONELIST_ORDER_DEFAULT; 2223/* string for sysctl */ 2224#define NUMA_ZONELIST_ORDER_LEN 16 2225char numa_zonelist_order[16] = "default"; 2226 2227/* 2228 * interface for configure zonelist ordering. 2229 * command line option "numa_zonelist_order" 2230 * = "[dD]efault - default, automatic configuration. 2231 * = "[nN]ode - order by node locality, then by zone within node 2232 * = "[zZ]one - order by zone, then by locality within zone 2233 */ 2234 2235static int __parse_numa_zonelist_order(char *s) 2236{ 2237 if (*s == 'd' || *s == 'D') { 2238 user_zonelist_order = ZONELIST_ORDER_DEFAULT; 2239 } else if (*s == 'n' || *s == 'N') { 2240 user_zonelist_order = ZONELIST_ORDER_NODE; 2241 } else if (*s == 'z' || *s == 'Z') { 2242 user_zonelist_order = ZONELIST_ORDER_ZONE; 2243 } else { 2244 printk(KERN_WARNING 2245 "Ignoring invalid numa_zonelist_order value: " 2246 "%s\n", s); 2247 return -EINVAL; 2248 } 2249 return 0; 2250} 2251 2252static __init int setup_numa_zonelist_order(char *s) 2253{ 2254 if (s) 2255 return __parse_numa_zonelist_order(s); 2256 return 0; 2257} 2258early_param("numa_zonelist_order", setup_numa_zonelist_order); 2259 2260/* 2261 * sysctl handler for numa_zonelist_order 2262 */ 2263int numa_zonelist_order_handler(ctl_table *table, int write, 2264 struct file *file, void __user *buffer, size_t *length, 2265 loff_t *ppos) 2266{ 2267 char saved_string[NUMA_ZONELIST_ORDER_LEN]; 2268 int ret; 2269 2270 if (write) 2271 strncpy(saved_string, (char*)table->data, 2272 NUMA_ZONELIST_ORDER_LEN); 2273 ret = proc_dostring(table, write, file, buffer, length, ppos); 2274 if (ret) 2275 return ret; 2276 if (write) { 2277 int oldval = user_zonelist_order; 2278 if (__parse_numa_zonelist_order((char*)table->data)) { 2279 /* 2280 * bogus value. restore saved string 2281 */ 2282 strncpy((char*)table->data, saved_string, 2283 NUMA_ZONELIST_ORDER_LEN); 2284 user_zonelist_order = oldval; 2285 } else if (oldval != user_zonelist_order) 2286 build_all_zonelists(); 2287 } 2288 return 0; 2289} 2290 2291 2292#define MAX_NODE_LOAD (nr_online_nodes) 2293static int node_load[MAX_NUMNODES]; 2294 2295/** 2296 * find_next_best_node - find the next node that should appear in a given node's fallback list 2297 * @node: node whose fallback list we're appending 2298 * @used_node_mask: nodemask_t of already used nodes 2299 * 2300 * We use a number of factors to determine which is the next node that should 2301 * appear on a given node's fallback list. The node should not have appeared 2302 * already in @node's fallback list, and it should be the next closest node 2303 * according to the distance array (which contains arbitrary distance values 2304 * from each node to each node in the system), and should also prefer nodes 2305 * with no CPUs, since presumably they'll have very little allocation pressure 2306 * on them otherwise. 2307 * It returns -1 if no node is found. 2308 */ 2309static int find_next_best_node(int node, nodemask_t *used_node_mask) 2310{ 2311 int n, val; 2312 int min_val = INT_MAX; 2313 int best_node = -1; 2314 const struct cpumask *tmp = cpumask_of_node(0); 2315 2316 /* Use the local node if we haven't already */ 2317 if (!node_isset(node, *used_node_mask)) { 2318 node_set(node, *used_node_mask); 2319 return node; 2320 } 2321 2322 for_each_node_state(n, N_HIGH_MEMORY) { 2323 2324 /* Don't want a node to appear more than once */ 2325 if (node_isset(n, *used_node_mask)) 2326 continue; 2327 2328 /* Use the distance array to find the distance */ 2329 val = node_distance(node, n); 2330 2331 /* Penalize nodes under us ("prefer the next node") */ 2332 val += (n < node); 2333 2334 /* Give preference to headless and unused nodes */ 2335 tmp = cpumask_of_node(n); 2336 if (!cpumask_empty(tmp)) 2337 val += PENALTY_FOR_NODE_WITH_CPUS; 2338 2339 /* Slight preference for less loaded node */ 2340 val *= (MAX_NODE_LOAD*MAX_NUMNODES); 2341 val += node_load[n]; 2342 2343 if (val < min_val) { 2344 min_val = val; 2345 best_node = n; 2346 } 2347 } 2348 2349 if (best_node >= 0) 2350 node_set(best_node, *used_node_mask); 2351 2352 return best_node; 2353} 2354 2355 2356/* 2357 * Build zonelists ordered by node and zones within node. 2358 * This results in maximum locality--normal zone overflows into local 2359 * DMA zone, if any--but risks exhausting DMA zone. 2360 */ 2361static void build_zonelists_in_node_order(pg_data_t *pgdat, int node) 2362{ 2363 int j; 2364 struct zonelist *zonelist; 2365 2366 zonelist = &pgdat->node_zonelists[0]; 2367 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++) 2368 ; 2369 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2370 MAX_NR_ZONES - 1); 2371 zonelist->_zonerefs[j].zone = NULL; 2372 zonelist->_zonerefs[j].zone_idx = 0; 2373} 2374 2375/* 2376 * Build gfp_thisnode zonelists 2377 */ 2378static void build_thisnode_zonelists(pg_data_t *pgdat) 2379{ 2380 int j; 2381 struct zonelist *zonelist; 2382 2383 zonelist = &pgdat->node_zonelists[1]; 2384 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); 2385 zonelist->_zonerefs[j].zone = NULL; 2386 zonelist->_zonerefs[j].zone_idx = 0; 2387} 2388 2389/* 2390 * Build zonelists ordered by zone and nodes within zones. 2391 * This results in conserving DMA zone[s] until all Normal memory is 2392 * exhausted, but results in overflowing to remote node while memory 2393 * may still exist in local DMA zone. 2394 */ 2395static int node_order[MAX_NUMNODES]; 2396 2397static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes) 2398{ 2399 int pos, j, node; 2400 int zone_type; /* needs to be signed */ 2401 struct zone *z; 2402 struct zonelist *zonelist; 2403 2404 zonelist = &pgdat->node_zonelists[0]; 2405 pos = 0; 2406 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) { 2407 for (j = 0; j < nr_nodes; j++) { 2408 node = node_order[j]; 2409 z = &NODE_DATA(node)->node_zones[zone_type]; 2410 if (populated_zone(z)) { 2411 zoneref_set_zone(z, 2412 &zonelist->_zonerefs[pos++]); 2413 check_highest_zone(zone_type); 2414 } 2415 } 2416 } 2417 zonelist->_zonerefs[pos].zone = NULL; 2418 zonelist->_zonerefs[pos].zone_idx = 0; 2419} 2420 2421static int default_zonelist_order(void) 2422{ 2423 int nid, zone_type; 2424 unsigned long low_kmem_size,total_size; 2425 struct zone *z; 2426 int average_size; 2427 /* 2428 * ZONE_DMA and ZONE_DMA32 can be very small area in the sytem. 2429 * If they are really small and used heavily, the system can fall 2430 * into OOM very easily. 2431 * This function detect ZONE_DMA/DMA32 size and confgigures zone order. 2432 */ 2433 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */ 2434 low_kmem_size = 0; 2435 total_size = 0; 2436 for_each_online_node(nid) { 2437 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { 2438 z = &NODE_DATA(nid)->node_zones[zone_type]; 2439 if (populated_zone(z)) { 2440 if (zone_type < ZONE_NORMAL) 2441 low_kmem_size += z->present_pages; 2442 total_size += z->present_pages; 2443 } 2444 } 2445 } 2446 if (!low_kmem_size || /* there are no DMA area. */ 2447 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */ 2448 return ZONELIST_ORDER_NODE; 2449 /* 2450 * look into each node's config. 2451 * If there is a node whose DMA/DMA32 memory is very big area on 2452 * local memory, NODE_ORDER may be suitable. 2453 */ 2454 average_size = total_size / 2455 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1); 2456 for_each_online_node(nid) { 2457 low_kmem_size = 0; 2458 total_size = 0; 2459 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { 2460 z = &NODE_DATA(nid)->node_zones[zone_type]; 2461 if (populated_zone(z)) { 2462 if (zone_type < ZONE_NORMAL) 2463 low_kmem_size += z->present_pages; 2464 total_size += z->present_pages; 2465 } 2466 } 2467 if (low_kmem_size && 2468 total_size > average_size && /* ignore small node */ 2469 low_kmem_size > total_size * 70/100) 2470 return ZONELIST_ORDER_NODE; 2471 } 2472 return ZONELIST_ORDER_ZONE; 2473} 2474 2475static void set_zonelist_order(void) 2476{ 2477 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT) 2478 current_zonelist_order = default_zonelist_order(); 2479 else 2480 current_zonelist_order = user_zonelist_order; 2481} 2482 2483static void build_zonelists(pg_data_t *pgdat) 2484{ 2485 int j, node, load; 2486 enum zone_type i; 2487 nodemask_t used_mask; 2488 int local_node, prev_node; 2489 struct zonelist *zonelist; 2490 int order = current_zonelist_order; 2491 2492 /* initialize zonelists */ 2493 for (i = 0; i < MAX_ZONELISTS; i++) { 2494 zonelist = pgdat->node_zonelists + i; 2495 zonelist->_zonerefs[0].zone = NULL; 2496 zonelist->_zonerefs[0].zone_idx = 0; 2497 } 2498 2499 /* NUMA-aware ordering of nodes */ 2500 local_node = pgdat->node_id; 2501 load = nr_online_nodes; 2502 prev_node = local_node; 2503 nodes_clear(used_mask); 2504 2505 memset(node_load, 0, sizeof(node_load)); 2506 memset(node_order, 0, sizeof(node_order)); 2507 j = 0; 2508 2509 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { 2510 int distance = node_distance(local_node, node); 2511 2512 /* 2513 * If another node is sufficiently far away then it is better 2514 * to reclaim pages in a zone before going off node. 2515 */ 2516 if (distance > RECLAIM_DISTANCE) 2517 zone_reclaim_mode = 1; 2518 2519 /* 2520 * We don't want to pressure a particular node. 2521 * So adding penalty to the first node in same 2522 * distance group to make it round-robin. 2523 */ 2524 if (distance != node_distance(local_node, prev_node)) 2525 node_load[node] = load; 2526 2527 prev_node = node; 2528 load--; 2529 if (order == ZONELIST_ORDER_NODE) 2530 build_zonelists_in_node_order(pgdat, node); 2531 else 2532 node_order[j++] = node; /* remember order */ 2533 } 2534 2535 if (order == ZONELIST_ORDER_ZONE) { 2536 /* calculate node order -- i.e., DMA last! */ 2537 build_zonelists_in_zone_order(pgdat, j); 2538 } 2539 2540 build_thisnode_zonelists(pgdat); 2541} 2542 2543/* Construct the zonelist performance cache - see further mmzone.h */ 2544static void build_zonelist_cache(pg_data_t *pgdat) 2545{ 2546 struct zonelist *zonelist; 2547 struct zonelist_cache *zlc; 2548 struct zoneref *z; 2549 2550 zonelist = &pgdat->node_zonelists[0]; 2551 zonelist->zlcache_ptr = zlc = &zonelist->zlcache; 2552 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); 2553 for (z = zonelist->_zonerefs; z->zone; z++) 2554 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z); 2555} 2556 2557 2558#else /* CONFIG_NUMA */ 2559 2560static void set_zonelist_order(void) 2561{ 2562 current_zonelist_order = ZONELIST_ORDER_ZONE; 2563} 2564 2565static void build_zonelists(pg_data_t *pgdat) 2566{ 2567 int node, local_node; 2568 enum zone_type j; 2569 struct zonelist *zonelist; 2570 2571 local_node = pgdat->node_id; 2572 2573 zonelist = &pgdat->node_zonelists[0]; 2574 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); 2575 2576 /* 2577 * Now we build the zonelist so that it contains the zones 2578 * of all the other nodes. 2579 * We don't want to pressure a particular node, so when 2580 * building the zones for node N, we make sure that the 2581 * zones coming right after the local ones are those from 2582 * node N+1 (modulo N) 2583 */ 2584 for (node = local_node + 1; node < MAX_NUMNODES; node++) { 2585 if (!node_online(node)) 2586 continue; 2587 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2588 MAX_NR_ZONES - 1); 2589 } 2590 for (node = 0; node < local_node; node++) { 2591 if (!node_online(node)) 2592 continue; 2593 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2594 MAX_NR_ZONES - 1); 2595 } 2596 2597 zonelist->_zonerefs[j].zone = NULL; 2598 zonelist->_zonerefs[j].zone_idx = 0; 2599} 2600 2601/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */ 2602static void build_zonelist_cache(pg_data_t *pgdat) 2603{ 2604 pgdat->node_zonelists[0].zlcache_ptr = NULL; 2605} 2606 2607#endif /* CONFIG_NUMA */ 2608 2609/* return values int ....just for stop_machine() */ 2610static int __build_all_zonelists(void *dummy) 2611{ 2612 int nid; 2613 2614 for_each_online_node(nid) { 2615 pg_data_t *pgdat = NODE_DATA(nid); 2616 2617 build_zonelists(pgdat); 2618 build_zonelist_cache(pgdat); 2619 } 2620 return 0; 2621} 2622 2623void build_all_zonelists(void) 2624{ 2625 set_zonelist_order(); 2626 2627 if (system_state == SYSTEM_BOOTING) { 2628 __build_all_zonelists(NULL); 2629 mminit_verify_zonelist(); 2630 cpuset_init_current_mems_allowed(); 2631 } else { 2632 /* we have to stop all cpus to guarantee there is no user 2633 of zonelist */ 2634 stop_machine(__build_all_zonelists, NULL, NULL); 2635 /* cpuset refresh routine should be here */ 2636 } 2637 vm_total_pages = nr_free_pagecache_pages(); 2638 /* 2639 * Disable grouping by mobility if the number of pages in the 2640 * system is too low to allow the mechanism to work. It would be 2641 * more accurate, but expensive to check per-zone. This check is 2642 * made on memory-hotadd so a system can start with mobility 2643 * disabled and enable it later 2644 */ 2645 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES)) 2646 page_group_by_mobility_disabled = 1; 2647 else 2648 page_group_by_mobility_disabled = 0; 2649 2650 printk("Built %i zonelists in %s order, mobility grouping %s. " 2651 "Total pages: %ld\n", 2652 nr_online_nodes, 2653 zonelist_order_name[current_zonelist_order], 2654 page_group_by_mobility_disabled ? "off" : "on", 2655 vm_total_pages); 2656#ifdef CONFIG_NUMA 2657 printk("Policy zone: %s\n", zone_names[policy_zone]); 2658#endif 2659} 2660 2661/* 2662 * Helper functions to size the waitqueue hash table. 2663 * Essentially these want to choose hash table sizes sufficiently 2664 * large so that collisions trying to wait on pages are rare. 2665 * But in fact, the number of active page waitqueues on typical 2666 * systems is ridiculously low, less than 200. So this is even 2667 * conservative, even though it seems large. 2668 * 2669 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to 2670 * waitqueues, i.e. the size of the waitq table given the number of pages. 2671 */ 2672#define PAGES_PER_WAITQUEUE 256 2673 2674#ifndef CONFIG_MEMORY_HOTPLUG 2675static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) 2676{ 2677 unsigned long size = 1; 2678 2679 pages /= PAGES_PER_WAITQUEUE; 2680 2681 while (size < pages) 2682 size <<= 1; 2683 2684 /* 2685 * Once we have dozens or even hundreds of threads sleeping 2686 * on IO we've got bigger problems than wait queue collision. 2687 * Limit the size of the wait table to a reasonable size. 2688 */ 2689 size = min(size, 4096UL); 2690 2691 return max(size, 4UL); 2692} 2693#else 2694/* 2695 * A zone's size might be changed by hot-add, so it is not possible to determine 2696 * a suitable size for its wait_table. So we use the maximum size now. 2697 * 2698 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie: 2699 * 2700 * i386 (preemption config) : 4096 x 16 = 64Kbyte. 2701 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte. 2702 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte. 2703 * 2704 * The maximum entries are prepared when a zone's memory is (512K + 256) pages 2705 * or more by the traditional way. (See above). It equals: 2706 * 2707 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte. 2708 * ia64(16K page size) : = ( 8G + 4M)byte. 2709 * powerpc (64K page size) : = (32G +16M)byte. 2710 */ 2711static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) 2712{ 2713 return 4096UL; 2714} 2715#endif 2716 2717/* 2718 * This is an integer logarithm so that shifts can be used later 2719 * to extract the more random high bits from the multiplicative 2720 * hash function before the remainder is taken. 2721 */ 2722static inline unsigned long wait_table_bits(unsigned long size) 2723{ 2724 return ffz(~size); 2725} 2726 2727#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1)) 2728 2729/* 2730 * Mark a number of pageblocks as MIGRATE_RESERVE. The number 2731 * of blocks reserved is based on min_wmark_pages(zone). The memory within 2732 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes 2733 * higher will lead to a bigger reserve which will get freed as contiguous 2734 * blocks as reclaim kicks in 2735 */ 2736static void setup_zone_migrate_reserve(struct zone *zone) 2737{ 2738 unsigned long start_pfn, pfn, end_pfn; 2739 struct page *page; 2740 unsigned long reserve, block_migratetype; 2741 2742 /* Get the start pfn, end pfn and the number of blocks to reserve */ 2743 start_pfn = zone->zone_start_pfn; 2744 end_pfn = start_pfn + zone->spanned_pages; 2745 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >> 2746 pageblock_order; 2747 2748 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { 2749 if (!pfn_valid(pfn)) 2750 continue; 2751 page = pfn_to_page(pfn); 2752 2753 /* Watch out for overlapping nodes */ 2754 if (page_to_nid(page) != zone_to_nid(zone)) 2755 continue; 2756 2757 /* Blocks with reserved pages will never free, skip them. */ 2758 if (PageReserved(page)) 2759 continue; 2760 2761 block_migratetype = get_pageblock_migratetype(page); 2762 2763 /* If this block is reserved, account for it */ 2764 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) { 2765 reserve--; 2766 continue; 2767 } 2768 2769 /* Suitable for reserving if this block is movable */ 2770 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) { 2771 set_pageblock_migratetype(page, MIGRATE_RESERVE); 2772 move_freepages_block(zone, page, MIGRATE_RESERVE); 2773 reserve--; 2774 continue; 2775 } 2776 2777 /* 2778 * If the reserve is met and this is a previous reserved block, 2779 * take it back 2780 */ 2781 if (block_migratetype == MIGRATE_RESERVE) { 2782 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 2783 move_freepages_block(zone, page, MIGRATE_MOVABLE); 2784 } 2785 } 2786} 2787 2788/* 2789 * Initially all pages are reserved - free ones are freed 2790 * up by free_all_bootmem() once the early boot process is 2791 * done. Non-atomic initialization, single-pass. 2792 */ 2793void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, 2794 unsigned long start_pfn, enum memmap_context context) 2795{ 2796 struct page *page; 2797 unsigned long end_pfn = start_pfn + size; 2798 unsigned long pfn; 2799 struct zone *z; 2800 2801 if (highest_memmap_pfn < end_pfn - 1) 2802 highest_memmap_pfn = end_pfn - 1; 2803 2804 z = &NODE_DATA(nid)->node_zones[zone]; 2805 for (pfn = start_pfn; pfn < end_pfn; pfn++) { 2806 /* 2807 * There can be holes in boot-time mem_map[]s 2808 * handed to this function. They do not 2809 * exist on hotplugged memory. 2810 */ 2811 if (context == MEMMAP_EARLY) { 2812 if (!early_pfn_valid(pfn)) 2813 continue; 2814 if (!early_pfn_in_nid(pfn, nid)) 2815 continue; 2816 } 2817 page = pfn_to_page(pfn); 2818 set_page_links(page, zone, nid, pfn); 2819 mminit_verify_page_links(page, zone, nid, pfn); 2820 init_page_count(page); 2821 reset_page_mapcount(page); 2822 SetPageReserved(page); 2823 /* 2824 * Mark the block movable so that blocks are reserved for 2825 * movable at startup. This will force kernel allocations 2826 * to reserve their blocks rather than leaking throughout 2827 * the address space during boot when many long-lived 2828 * kernel allocations are made. Later some blocks near 2829 * the start are marked MIGRATE_RESERVE by 2830 * setup_zone_migrate_reserve() 2831 * 2832 * bitmap is created for zone's valid pfn range. but memmap 2833 * can be created for invalid pages (for alignment) 2834 * check here not to call set_pageblock_migratetype() against 2835 * pfn out of zone. 2836 */ 2837 if ((z->zone_start_pfn <= pfn) 2838 && (pfn < z->zone_start_pfn + z->spanned_pages) 2839 && !(pfn & (pageblock_nr_pages - 1))) 2840 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 2841 2842 INIT_LIST_HEAD(&page->lru); 2843#ifdef WANT_PAGE_VIRTUAL 2844 /* The shift won't overflow because ZONE_NORMAL is below 4G. */ 2845 if (!is_highmem_idx(zone)) 2846 set_page_address(page, __va(pfn << PAGE_SHIFT)); 2847#endif 2848 } 2849} 2850 2851static void __meminit zone_init_free_lists(struct zone *zone) 2852{ 2853 int order, t; 2854 for_each_migratetype_order(order, t) { 2855 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); 2856 zone->free_area[order].nr_free = 0; 2857 } 2858} 2859 2860#ifndef __HAVE_ARCH_MEMMAP_INIT 2861#define memmap_init(size, nid, zone, start_pfn) \ 2862 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY) 2863#endif 2864 2865static int zone_batchsize(struct zone *zone) 2866{ 2867#ifdef CONFIG_MMU 2868 int batch; 2869 2870 /* 2871 * The per-cpu-pages pools are set to around 1000th of the 2872 * size of the zone. But no more than 1/2 of a meg. 2873 * 2874 * OK, so we don't know how big the cache is. So guess. 2875 */ 2876 batch = zone->present_pages / 1024; 2877 if (batch * PAGE_SIZE > 512 * 1024) 2878 batch = (512 * 1024) / PAGE_SIZE; 2879 batch /= 4; /* We effectively *= 4 below */ 2880 if (batch < 1) 2881 batch = 1; 2882 2883 /* 2884 * Clamp the batch to a 2^n - 1 value. Having a power 2885 * of 2 value was found to be more likely to have 2886 * suboptimal cache aliasing properties in some cases. 2887 * 2888 * For example if 2 tasks are alternately allocating 2889 * batches of pages, one task can end up with a lot 2890 * of pages of one half of the possible page colors 2891 * and the other with pages of the other colors. 2892 */ 2893 batch = rounddown_pow_of_two(batch + batch/2) - 1; 2894 2895 return batch; 2896 2897#else 2898 /* The deferral and batching of frees should be suppressed under NOMMU 2899 * conditions. 2900 * 2901 * The problem is that NOMMU needs to be able to allocate large chunks 2902 * of contiguous memory as there's no hardware page translation to 2903 * assemble apparent contiguous memory from discontiguous pages. 2904 * 2905 * Queueing large contiguous runs of pages for batching, however, 2906 * causes the pages to actually be freed in smaller chunks. As there 2907 * can be a significant delay between the individual batches being 2908 * recycled, this leads to the once large chunks of space being 2909 * fragmented and becoming unavailable for high-order allocations. 2910 */ 2911 return 0; 2912#endif 2913} 2914 2915static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) 2916{ 2917 struct per_cpu_pages *pcp; 2918 2919 memset(p, 0, sizeof(*p)); 2920 2921 pcp = &p->pcp; 2922 pcp->count = 0; 2923 pcp->high = 6 * batch; 2924 pcp->batch = max(1UL, 1 * batch); 2925 INIT_LIST_HEAD(&pcp->list); 2926} 2927 2928/* 2929 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist 2930 * to the value high for the pageset p. 2931 */ 2932 2933static void setup_pagelist_highmark(struct per_cpu_pageset *p, 2934 unsigned long high) 2935{ 2936 struct per_cpu_pages *pcp; 2937 2938 pcp = &p->pcp; 2939 pcp->high = high; 2940 pcp->batch = max(1UL, high/4); 2941 if ((high/4) > (PAGE_SHIFT * 8)) 2942 pcp->batch = PAGE_SHIFT * 8; 2943} 2944 2945 2946#ifdef CONFIG_NUMA 2947/* 2948 * Boot pageset table. One per cpu which is going to be used for all 2949 * zones and all nodes. The parameters will be set in such a way 2950 * that an item put on a list will immediately be handed over to 2951 * the buddy list. This is safe since pageset manipulation is done 2952 * with interrupts disabled. 2953 * 2954 * Some NUMA counter updates may also be caught by the boot pagesets. 2955 * 2956 * The boot_pagesets must be kept even after bootup is complete for 2957 * unused processors and/or zones. They do play a role for bootstrapping 2958 * hotplugged processors. 2959 * 2960 * zoneinfo_show() and maybe other functions do 2961 * not check if the processor is online before following the pageset pointer. 2962 * Other parts of the kernel may not check if the zone is available. 2963 */ 2964static struct per_cpu_pageset boot_pageset[NR_CPUS]; 2965 2966/* 2967 * Dynamically allocate memory for the 2968 * per cpu pageset array in struct zone. 2969 */ 2970static int __cpuinit process_zones(int cpu) 2971{ 2972 struct zone *zone, *dzone; 2973 int node = cpu_to_node(cpu); 2974 2975 node_set_state(node, N_CPU); /* this node has a cpu */ 2976 2977 for_each_populated_zone(zone) { 2978 zone_pcp(zone, cpu) = kmalloc_node(sizeof(struct per_cpu_pageset), 2979 GFP_KERNEL, node); 2980 if (!zone_pcp(zone, cpu)) 2981 goto bad; 2982 2983 setup_pageset(zone_pcp(zone, cpu), zone_batchsize(zone)); 2984 2985 if (percpu_pagelist_fraction) 2986 setup_pagelist_highmark(zone_pcp(zone, cpu), 2987 (zone->present_pages / percpu_pagelist_fraction)); 2988 } 2989 2990 return 0; 2991bad: 2992 for_each_zone(dzone) { 2993 if (!populated_zone(dzone)) 2994 continue; 2995 if (dzone == zone) 2996 break; 2997 kfree(zone_pcp(dzone, cpu)); 2998 zone_pcp(dzone, cpu) = NULL; 2999 } 3000 return -ENOMEM; 3001} 3002 3003static inline void free_zone_pagesets(int cpu) 3004{ 3005 struct zone *zone; 3006 3007 for_each_zone(zone) { 3008 struct per_cpu_pageset *pset = zone_pcp(zone, cpu); 3009 3010 /* Free per_cpu_pageset if it is slab allocated */ 3011 if (pset != &boot_pageset[cpu]) 3012 kfree(pset); 3013 zone_pcp(zone, cpu) = NULL; 3014 } 3015} 3016 3017static int __cpuinit pageset_cpuup_callback(struct notifier_block *nfb, 3018 unsigned long action, 3019 void *hcpu) 3020{ 3021 int cpu = (long)hcpu; 3022 int ret = NOTIFY_OK; 3023 3024 switch (action) { 3025 case CPU_UP_PREPARE: 3026 case CPU_UP_PREPARE_FROZEN: 3027 if (process_zones(cpu)) 3028 ret = NOTIFY_BAD; 3029 break; 3030 case CPU_UP_CANCELED: 3031 case CPU_UP_CANCELED_FROZEN: 3032 case CPU_DEAD: 3033 case CPU_DEAD_FROZEN: 3034 free_zone_pagesets(cpu); 3035 break; 3036 default: 3037 break; 3038 } 3039 return ret; 3040} 3041 3042static struct notifier_block __cpuinitdata pageset_notifier = 3043 { &pageset_cpuup_callback, NULL, 0 }; 3044 3045void __init setup_per_cpu_pageset(void) 3046{ 3047 int err; 3048 3049 /* Initialize per_cpu_pageset for cpu 0. 3050 * A cpuup callback will do this for every cpu 3051 * as it comes online 3052 */ 3053 err = process_zones(smp_processor_id()); 3054 BUG_ON(err); 3055 register_cpu_notifier(&pageset_notifier); 3056} 3057 3058#endif 3059 3060static noinline __init_refok 3061int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages) 3062{ 3063 int i; 3064 struct pglist_data *pgdat = zone->zone_pgdat; 3065 size_t alloc_size; 3066 3067 /* 3068 * The per-page waitqueue mechanism uses hashed waitqueues 3069 * per zone. 3070 */ 3071 zone->wait_table_hash_nr_entries = 3072 wait_table_hash_nr_entries(zone_size_pages); 3073 zone->wait_table_bits = 3074 wait_table_bits(zone->wait_table_hash_nr_entries); 3075 alloc_size = zone->wait_table_hash_nr_entries 3076 * sizeof(wait_queue_head_t); 3077 3078 if (!slab_is_available()) { 3079 zone->wait_table = (wait_queue_head_t *) 3080 alloc_bootmem_node(pgdat, alloc_size); 3081 } else { 3082 /* 3083 * This case means that a zone whose size was 0 gets new memory 3084 * via memory hot-add. 3085 * But it may be the case that a new node was hot-added. In 3086 * this case vmalloc() will not be able to use this new node's 3087 * memory - this wait_table must be initialized to use this new 3088 * node itself as well. 3089 * To use this new node's memory, further consideration will be 3090 * necessary. 3091 */ 3092 zone->wait_table = vmalloc(alloc_size); 3093 } 3094 if (!zone->wait_table) 3095 return -ENOMEM; 3096 3097 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i) 3098 init_waitqueue_head(zone->wait_table + i); 3099 3100 return 0; 3101} 3102 3103static __meminit void zone_pcp_init(struct zone *zone) 3104{ 3105 int cpu; 3106 unsigned long batch = zone_batchsize(zone); 3107 3108 for (cpu = 0; cpu < NR_CPUS; cpu++) { 3109#ifdef CONFIG_NUMA 3110 /* Early boot. Slab allocator not functional yet */ 3111 zone_pcp(zone, cpu) = &boot_pageset[cpu]; 3112 setup_pageset(&boot_pageset[cpu],0); 3113#else 3114 setup_pageset(zone_pcp(zone,cpu), batch); 3115#endif 3116 } 3117 if (zone->present_pages) 3118 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%lu\n", 3119 zone->name, zone->present_pages, batch); 3120} 3121 3122__meminit int init_currently_empty_zone(struct zone *zone, 3123 unsigned long zone_start_pfn, 3124 unsigned long size, 3125 enum memmap_context context) 3126{ 3127 struct pglist_data *pgdat = zone->zone_pgdat; 3128 int ret; 3129 ret = zone_wait_table_init(zone, size); 3130 if (ret) 3131 return ret; 3132 pgdat->nr_zones = zone_idx(zone) + 1; 3133 3134 zone->zone_start_pfn = zone_start_pfn; 3135 3136 mminit_dprintk(MMINIT_TRACE, "memmap_init", 3137 "Initialising map node %d zone %lu pfns %lu -> %lu\n", 3138 pgdat->node_id, 3139 (unsigned long)zone_idx(zone), 3140 zone_start_pfn, (zone_start_pfn + size)); 3141 3142 zone_init_free_lists(zone); 3143 3144 return 0; 3145} 3146 3147#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 3148/* 3149 * Basic iterator support. Return the first range of PFNs for a node 3150 * Note: nid == MAX_NUMNODES returns first region regardless of node 3151 */ 3152static int __meminit first_active_region_index_in_nid(int nid) 3153{ 3154 int i; 3155 3156 for (i = 0; i < nr_nodemap_entries; i++) 3157 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid) 3158 return i; 3159 3160 return -1; 3161} 3162 3163/* 3164 * Basic iterator support. Return the next active range of PFNs for a node 3165 * Note: nid == MAX_NUMNODES returns next region regardless of node 3166 */ 3167static int __meminit next_active_region_index_in_nid(int index, int nid) 3168{ 3169 for (index = index + 1; index < nr_nodemap_entries; index++) 3170 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid) 3171 return index; 3172 3173 return -1; 3174} 3175 3176#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID 3177/* 3178 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. 3179 * Architectures may implement their own version but if add_active_range() 3180 * was used and there are no special requirements, this is a convenient 3181 * alternative 3182 */ 3183int __meminit __early_pfn_to_nid(unsigned long pfn) 3184{ 3185 int i; 3186 3187 for (i = 0; i < nr_nodemap_entries; i++) { 3188 unsigned long start_pfn = early_node_map[i].start_pfn; 3189 unsigned long end_pfn = early_node_map[i].end_pfn; 3190 3191 if (start_pfn <= pfn && pfn < end_pfn) 3192 return early_node_map[i].nid; 3193 } 3194 /* This is a memory hole */ 3195 return -1; 3196} 3197#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ 3198 3199int __meminit early_pfn_to_nid(unsigned long pfn) 3200{ 3201 int nid; 3202 3203 nid = __early_pfn_to_nid(pfn); 3204 if (nid >= 0) 3205 return nid; 3206 /* just returns 0 */ 3207 return 0; 3208} 3209 3210#ifdef CONFIG_NODES_SPAN_OTHER_NODES 3211bool __meminit early_pfn_in_nid(unsigned long pfn, int node) 3212{ 3213 int nid; 3214 3215 nid = __early_pfn_to_nid(pfn); 3216 if (nid >= 0 && nid != node) 3217 return false; 3218 return true; 3219} 3220#endif 3221 3222/* Basic iterator support to walk early_node_map[] */ 3223#define for_each_active_range_index_in_nid(i, nid) \ 3224 for (i = first_active_region_index_in_nid(nid); i != -1; \ 3225 i = next_active_region_index_in_nid(i, nid)) 3226 3227/** 3228 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range 3229 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed. 3230 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node 3231 * 3232 * If an architecture guarantees that all ranges registered with 3233 * add_active_ranges() contain no holes and may be freed, this 3234 * this function may be used instead of calling free_bootmem() manually. 3235 */ 3236void __init free_bootmem_with_active_regions(int nid, 3237 unsigned long max_low_pfn) 3238{ 3239 int i; 3240 3241 for_each_active_range_index_in_nid(i, nid) { 3242 unsigned long size_pages = 0; 3243 unsigned long end_pfn = early_node_map[i].end_pfn; 3244 3245 if (early_node_map[i].start_pfn >= max_low_pfn) 3246 continue; 3247 3248 if (end_pfn > max_low_pfn) 3249 end_pfn = max_low_pfn; 3250 3251 size_pages = end_pfn - early_node_map[i].start_pfn; 3252 free_bootmem_node(NODE_DATA(early_node_map[i].nid), 3253 PFN_PHYS(early_node_map[i].start_pfn), 3254 size_pages << PAGE_SHIFT); 3255 } 3256} 3257 3258void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data) 3259{ 3260 int i; 3261 int ret; 3262 3263 for_each_active_range_index_in_nid(i, nid) { 3264 ret = work_fn(early_node_map[i].start_pfn, 3265 early_node_map[i].end_pfn, data); 3266 if (ret) 3267 break; 3268 } 3269} 3270/** 3271 * sparse_memory_present_with_active_regions - Call memory_present for each active range 3272 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used. 3273 * 3274 * If an architecture guarantees that all ranges registered with 3275 * add_active_ranges() contain no holes and may be freed, this 3276 * function may be used instead of calling memory_present() manually. 3277 */ 3278void __init sparse_memory_present_with_active_regions(int nid) 3279{ 3280 int i; 3281 3282 for_each_active_range_index_in_nid(i, nid) 3283 memory_present(early_node_map[i].nid, 3284 early_node_map[i].start_pfn, 3285 early_node_map[i].end_pfn); 3286} 3287 3288/** 3289 * get_pfn_range_for_nid - Return the start and end page frames for a node 3290 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. 3291 * @start_pfn: Passed by reference. On return, it will have the node start_pfn. 3292 * @end_pfn: Passed by reference. On return, it will have the node end_pfn. 3293 * 3294 * It returns the start and end page frame of a node based on information 3295 * provided by an arch calling add_active_range(). If called for a node 3296 * with no available memory, a warning is printed and the start and end 3297 * PFNs will be 0. 3298 */ 3299void __meminit get_pfn_range_for_nid(unsigned int nid, 3300 unsigned long *start_pfn, unsigned long *end_pfn) 3301{ 3302 int i; 3303 *start_pfn = -1UL; 3304 *end_pfn = 0; 3305 3306 for_each_active_range_index_in_nid(i, nid) { 3307 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn); 3308 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn); 3309 } 3310 3311 if (*start_pfn == -1UL) 3312 *start_pfn = 0; 3313} 3314 3315/* 3316 * This finds a zone that can be used for ZONE_MOVABLE pages. The 3317 * assumption is made that zones within a node are ordered in monotonic 3318 * increasing memory addresses so that the "highest" populated zone is used 3319 */ 3320static void __init find_usable_zone_for_movable(void) 3321{ 3322 int zone_index; 3323 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { 3324 if (zone_index == ZONE_MOVABLE) 3325 continue; 3326 3327 if (arch_zone_highest_possible_pfn[zone_index] > 3328 arch_zone_lowest_possible_pfn[zone_index]) 3329 break; 3330 } 3331 3332 VM_BUG_ON(zone_index == -1); 3333 movable_zone = zone_index; 3334} 3335 3336/* 3337 * The zone ranges provided by the architecture do not include ZONE_MOVABLE 3338 * because it is sized independant of architecture. Unlike the other zones, 3339 * the starting point for ZONE_MOVABLE is not fixed. It may be different 3340 * in each node depending on the size of each node and how evenly kernelcore 3341 * is distributed. This helper function adjusts the zone ranges 3342 * provided by the architecture for a given node by using the end of the 3343 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that 3344 * zones within a node are in order of monotonic increases memory addresses 3345 */ 3346static void __meminit adjust_zone_range_for_zone_movable(int nid, 3347 unsigned long zone_type, 3348 unsigned long node_start_pfn, 3349 unsigned long node_end_pfn, 3350 unsigned long *zone_start_pfn, 3351 unsigned long *zone_end_pfn) 3352{ 3353 /* Only adjust if ZONE_MOVABLE is on this node */ 3354 if (zone_movable_pfn[nid]) { 3355 /* Size ZONE_MOVABLE */ 3356 if (zone_type == ZONE_MOVABLE) { 3357 *zone_start_pfn = zone_movable_pfn[nid]; 3358 *zone_end_pfn = min(node_end_pfn, 3359 arch_zone_highest_possible_pfn[movable_zone]); 3360 3361 /* Adjust for ZONE_MOVABLE starting within this range */ 3362 } else if (*zone_start_pfn < zone_movable_pfn[nid] && 3363 *zone_end_pfn > zone_movable_pfn[nid]) { 3364 *zone_end_pfn = zone_movable_pfn[nid]; 3365 3366 /* Check if this whole range is within ZONE_MOVABLE */ 3367 } else if (*zone_start_pfn >= zone_movable_pfn[nid]) 3368 *zone_start_pfn = *zone_end_pfn; 3369 } 3370} 3371 3372/* 3373 * Return the number of pages a zone spans in a node, including holes 3374 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() 3375 */ 3376static unsigned long __meminit zone_spanned_pages_in_node(int nid, 3377 unsigned long zone_type, 3378 unsigned long *ignored) 3379{ 3380 unsigned long node_start_pfn, node_end_pfn; 3381 unsigned long zone_start_pfn, zone_end_pfn; 3382 3383 /* Get the start and end of the node and zone */ 3384 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); 3385 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; 3386 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; 3387 adjust_zone_range_for_zone_movable(nid, zone_type, 3388 node_start_pfn, node_end_pfn, 3389 &zone_start_pfn, &zone_end_pfn); 3390 3391 /* Check that this node has pages within the zone's required range */ 3392 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn) 3393 return 0; 3394 3395 /* Move the zone boundaries inside the node if necessary */ 3396 zone_end_pfn = min(zone_end_pfn, node_end_pfn); 3397 zone_start_pfn = max(zone_start_pfn, node_start_pfn); 3398 3399 /* Return the spanned pages */ 3400 return zone_end_pfn - zone_start_pfn; 3401} 3402 3403/* 3404 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, 3405 * then all holes in the requested range will be accounted for. 3406 */ 3407static unsigned long __meminit __absent_pages_in_range(int nid, 3408 unsigned long range_start_pfn, 3409 unsigned long range_end_pfn) 3410{ 3411 int i = 0; 3412 unsigned long prev_end_pfn = 0, hole_pages = 0; 3413 unsigned long start_pfn; 3414 3415 /* Find the end_pfn of the first active range of pfns in the node */ 3416 i = first_active_region_index_in_nid(nid); 3417 if (i == -1) 3418 return 0; 3419 3420 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn); 3421 3422 /* Account for ranges before physical memory on this node */ 3423 if (early_node_map[i].start_pfn > range_start_pfn) 3424 hole_pages = prev_end_pfn - range_start_pfn; 3425 3426 /* Find all holes for the zone within the node */ 3427 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) { 3428 3429 /* No need to continue if prev_end_pfn is outside the zone */ 3430 if (prev_end_pfn >= range_end_pfn) 3431 break; 3432 3433 /* Make sure the end of the zone is not within the hole */ 3434 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn); 3435 prev_end_pfn = max(prev_end_pfn, range_start_pfn); 3436 3437 /* Update the hole size cound and move on */ 3438 if (start_pfn > range_start_pfn) { 3439 BUG_ON(prev_end_pfn > start_pfn); 3440 hole_pages += start_pfn - prev_end_pfn; 3441 } 3442 prev_end_pfn = early_node_map[i].end_pfn; 3443 } 3444 3445 /* Account for ranges past physical memory on this node */ 3446 if (range_end_pfn > prev_end_pfn) 3447 hole_pages += range_end_pfn - 3448 max(range_start_pfn, prev_end_pfn); 3449 3450 return hole_pages; 3451} 3452 3453/** 3454 * absent_pages_in_range - Return number of page frames in holes within a range 3455 * @start_pfn: The start PFN to start searching for holes 3456 * @end_pfn: The end PFN to stop searching for holes 3457 * 3458 * It returns the number of pages frames in memory holes within a range. 3459 */ 3460unsigned long __init absent_pages_in_range(unsigned long start_pfn, 3461 unsigned long end_pfn) 3462{ 3463 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); 3464} 3465 3466/* Return the number of page frames in holes in a zone on a node */ 3467static unsigned long __meminit zone_absent_pages_in_node(int nid, 3468 unsigned long zone_type, 3469 unsigned long *ignored) 3470{ 3471 unsigned long node_start_pfn, node_end_pfn; 3472 unsigned long zone_start_pfn, zone_end_pfn; 3473 3474 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); 3475 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type], 3476 node_start_pfn); 3477 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type], 3478 node_end_pfn); 3479 3480 adjust_zone_range_for_zone_movable(nid, zone_type, 3481 node_start_pfn, node_end_pfn, 3482 &zone_start_pfn, &zone_end_pfn); 3483 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); 3484} 3485 3486#else 3487static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, 3488 unsigned long zone_type, 3489 unsigned long *zones_size) 3490{ 3491 return zones_size[zone_type]; 3492} 3493 3494static inline unsigned long __meminit zone_absent_pages_in_node(int nid, 3495 unsigned long zone_type, 3496 unsigned long *zholes_size) 3497{ 3498 if (!zholes_size) 3499 return 0; 3500 3501 return zholes_size[zone_type]; 3502} 3503 3504#endif 3505 3506static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, 3507 unsigned long *zones_size, unsigned long *zholes_size) 3508{ 3509 unsigned long realtotalpages, totalpages = 0; 3510 enum zone_type i; 3511 3512 for (i = 0; i < MAX_NR_ZONES; i++) 3513 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i, 3514 zones_size); 3515 pgdat->node_spanned_pages = totalpages; 3516 3517 realtotalpages = totalpages; 3518 for (i = 0; i < MAX_NR_ZONES; i++) 3519 realtotalpages -= 3520 zone_absent_pages_in_node(pgdat->node_id, i, 3521 zholes_size); 3522 pgdat->node_present_pages = realtotalpages; 3523 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, 3524 realtotalpages); 3525} 3526 3527#ifndef CONFIG_SPARSEMEM 3528/* 3529 * Calculate the size of the zone->blockflags rounded to an unsigned long 3530 * Start by making sure zonesize is a multiple of pageblock_order by rounding 3531 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally 3532 * round what is now in bits to nearest long in bits, then return it in 3533 * bytes. 3534 */ 3535static unsigned long __init usemap_size(unsigned long zonesize) 3536{ 3537 unsigned long usemapsize; 3538 3539 usemapsize = roundup(zonesize, pageblock_nr_pages); 3540 usemapsize = usemapsize >> pageblock_order; 3541 usemapsize *= NR_PAGEBLOCK_BITS; 3542 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); 3543 3544 return usemapsize / 8; 3545} 3546 3547static void __init setup_usemap(struct pglist_data *pgdat, 3548 struct zone *zone, unsigned long zonesize) 3549{ 3550 unsigned long usemapsize = usemap_size(zonesize); 3551 zone->pageblock_flags = NULL; 3552 if (usemapsize) 3553 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize); 3554} 3555#else 3556static void inline setup_usemap(struct pglist_data *pgdat, 3557 struct zone *zone, unsigned long zonesize) {} 3558#endif /* CONFIG_SPARSEMEM */ 3559 3560#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE 3561 3562/* Return a sensible default order for the pageblock size. */ 3563static inline int pageblock_default_order(void) 3564{ 3565 if (HPAGE_SHIFT > PAGE_SHIFT) 3566 return HUGETLB_PAGE_ORDER; 3567 3568 return MAX_ORDER-1; 3569} 3570 3571/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ 3572static inline void __init set_pageblock_order(unsigned int order) 3573{ 3574 /* Check that pageblock_nr_pages has not already been setup */ 3575 if (pageblock_order) 3576 return; 3577 3578 /* 3579 * Assume the largest contiguous order of interest is a huge page. 3580 * This value may be variable depending on boot parameters on IA64 3581 */ 3582 pageblock_order = order; 3583} 3584#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ 3585 3586/* 3587 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() 3588 * and pageblock_default_order() are unused as pageblock_order is set 3589 * at compile-time. See include/linux/pageblock-flags.h for the values of 3590 * pageblock_order based on the kernel config 3591 */ 3592static inline int pageblock_default_order(unsigned int order) 3593{ 3594 return MAX_ORDER-1; 3595} 3596#define set_pageblock_order(x) do {} while (0) 3597 3598#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ 3599 3600/* 3601 * Set up the zone data structures: 3602 * - mark all pages reserved 3603 * - mark all memory queues empty 3604 * - clear the memory bitmaps 3605 */ 3606static void __paginginit free_area_init_core(struct pglist_data *pgdat, 3607 unsigned long *zones_size, unsigned long *zholes_size) 3608{ 3609 enum zone_type j; 3610 int nid = pgdat->node_id; 3611 unsigned long zone_start_pfn = pgdat->node_start_pfn; 3612 int ret; 3613 3614 pgdat_resize_init(pgdat); 3615 pgdat->nr_zones = 0; 3616 init_waitqueue_head(&pgdat->kswapd_wait); 3617 pgdat->kswapd_max_order = 0; 3618 pgdat_page_cgroup_init(pgdat); 3619 3620 for (j = 0; j < MAX_NR_ZONES; j++) { 3621 struct zone *zone = pgdat->node_zones + j; 3622 unsigned long size, realsize, memmap_pages; 3623 enum lru_list l; 3624 3625 size = zone_spanned_pages_in_node(nid, j, zones_size); 3626 realsize = size - zone_absent_pages_in_node(nid, j, 3627 zholes_size); 3628 3629 /* 3630 * Adjust realsize so that it accounts for how much memory 3631 * is used by this zone for memmap. This affects the watermark 3632 * and per-cpu initialisations 3633 */ 3634 memmap_pages = 3635 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT; 3636 if (realsize >= memmap_pages) { 3637 realsize -= memmap_pages; 3638 if (memmap_pages) 3639 printk(KERN_DEBUG 3640 " %s zone: %lu pages used for memmap\n", 3641 zone_names[j], memmap_pages); 3642 } else 3643 printk(KERN_WARNING 3644 " %s zone: %lu pages exceeds realsize %lu\n", 3645 zone_names[j], memmap_pages, realsize); 3646 3647 /* Account for reserved pages */ 3648 if (j == 0 && realsize > dma_reserve) { 3649 realsize -= dma_reserve; 3650 printk(KERN_DEBUG " %s zone: %lu pages reserved\n", 3651 zone_names[0], dma_reserve); 3652 } 3653 3654 if (!is_highmem_idx(j)) 3655 nr_kernel_pages += realsize; 3656 nr_all_pages += realsize; 3657 3658 zone->spanned_pages = size; 3659 zone->present_pages = realsize; 3660#ifdef CONFIG_NUMA 3661 zone->node = nid; 3662 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio) 3663 / 100; 3664 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100; 3665#endif 3666 zone->name = zone_names[j]; 3667 spin_lock_init(&zone->lock); 3668 spin_lock_init(&zone->lru_lock); 3669 zone_seqlock_init(zone); 3670 zone->zone_pgdat = pgdat; 3671 3672 zone->prev_priority = DEF_PRIORITY; 3673 3674 zone_pcp_init(zone); 3675 for_each_lru(l) { 3676 INIT_LIST_HEAD(&zone->lru[l].list); 3677 zone->lru[l].nr_saved_scan = 0; 3678 } 3679 zone->reclaim_stat.recent_rotated[0] = 0; 3680 zone->reclaim_stat.recent_rotated[1] = 0; 3681 zone->reclaim_stat.recent_scanned[0] = 0; 3682 zone->reclaim_stat.recent_scanned[1] = 0; 3683 zap_zone_vm_stats(zone); 3684 zone->flags = 0; 3685 if (!size) 3686 continue; 3687 3688 set_pageblock_order(pageblock_default_order()); 3689 setup_usemap(pgdat, zone, size); 3690 ret = init_currently_empty_zone(zone, zone_start_pfn, 3691 size, MEMMAP_EARLY); 3692 BUG_ON(ret); 3693 memmap_init(size, nid, j, zone_start_pfn); 3694 zone_start_pfn += size; 3695 } 3696} 3697 3698static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat) 3699{ 3700 /* Skip empty nodes */ 3701 if (!pgdat->node_spanned_pages) 3702 return; 3703 3704#ifdef CONFIG_FLAT_NODE_MEM_MAP 3705 /* ia64 gets its own node_mem_map, before this, without bootmem */ 3706 if (!pgdat->node_mem_map) { 3707 unsigned long size, start, end; 3708 struct page *map; 3709 3710 /* 3711 * The zone's endpoints aren't required to be MAX_ORDER 3712 * aligned but the node_mem_map endpoints must be in order 3713 * for the buddy allocator to function correctly. 3714 */ 3715 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); 3716 end = pgdat->node_start_pfn + pgdat->node_spanned_pages; 3717 end = ALIGN(end, MAX_ORDER_NR_PAGES); 3718 size = (end - start) * sizeof(struct page); 3719 map = alloc_remap(pgdat->node_id, size); 3720 if (!map) 3721 map = alloc_bootmem_node(pgdat, size); 3722 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start); 3723 } 3724#ifndef CONFIG_NEED_MULTIPLE_NODES 3725 /* 3726 * With no DISCONTIG, the global mem_map is just set as node 0's 3727 */ 3728 if (pgdat == NODE_DATA(0)) { 3729 mem_map = NODE_DATA(0)->node_mem_map; 3730#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 3731 if (page_to_pfn(mem_map) != pgdat->node_start_pfn) 3732 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET); 3733#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 3734 } 3735#endif 3736#endif /* CONFIG_FLAT_NODE_MEM_MAP */ 3737} 3738 3739void __paginginit free_area_init_node(int nid, unsigned long *zones_size, 3740 unsigned long node_start_pfn, unsigned long *zholes_size) 3741{ 3742 pg_data_t *pgdat = NODE_DATA(nid); 3743 3744 pgdat->node_id = nid; 3745 pgdat->node_start_pfn = node_start_pfn; 3746 calculate_node_totalpages(pgdat, zones_size, zholes_size); 3747 3748 alloc_node_mem_map(pgdat); 3749#ifdef CONFIG_FLAT_NODE_MEM_MAP 3750 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n", 3751 nid, (unsigned long)pgdat, 3752 (unsigned long)pgdat->node_mem_map); 3753#endif 3754 3755 free_area_init_core(pgdat, zones_size, zholes_size); 3756} 3757 3758#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 3759 3760#if MAX_NUMNODES > 1 3761/* 3762 * Figure out the number of possible node ids. 3763 */ 3764static void __init setup_nr_node_ids(void) 3765{ 3766 unsigned int node; 3767 unsigned int highest = 0; 3768 3769 for_each_node_mask(node, node_possible_map) 3770 highest = node; 3771 nr_node_ids = highest + 1; 3772} 3773#else 3774static inline void setup_nr_node_ids(void) 3775{ 3776} 3777#endif 3778 3779/** 3780 * add_active_range - Register a range of PFNs backed by physical memory 3781 * @nid: The node ID the range resides on 3782 * @start_pfn: The start PFN of the available physical memory 3783 * @end_pfn: The end PFN of the available physical memory 3784 * 3785 * These ranges are stored in an early_node_map[] and later used by 3786 * free_area_init_nodes() to calculate zone sizes and holes. If the 3787 * range spans a memory hole, it is up to the architecture to ensure 3788 * the memory is not freed by the bootmem allocator. If possible 3789 * the range being registered will be merged with existing ranges. 3790 */ 3791void __init add_active_range(unsigned int nid, unsigned long start_pfn, 3792 unsigned long end_pfn) 3793{ 3794 int i; 3795 3796 mminit_dprintk(MMINIT_TRACE, "memory_register", 3797 "Entering add_active_range(%d, %#lx, %#lx) " 3798 "%d entries of %d used\n", 3799 nid, start_pfn, end_pfn, 3800 nr_nodemap_entries, MAX_ACTIVE_REGIONS); 3801 3802 mminit_validate_memmodel_limits(&start_pfn, &end_pfn); 3803 3804 /* Merge with existing active regions if possible */ 3805 for (i = 0; i < nr_nodemap_entries; i++) { 3806 if (early_node_map[i].nid != nid) 3807 continue; 3808 3809 /* Skip if an existing region covers this new one */ 3810 if (start_pfn >= early_node_map[i].start_pfn && 3811 end_pfn <= early_node_map[i].end_pfn) 3812 return; 3813 3814 /* Merge forward if suitable */ 3815 if (start_pfn <= early_node_map[i].end_pfn && 3816 end_pfn > early_node_map[i].end_pfn) { 3817 early_node_map[i].end_pfn = end_pfn; 3818 return; 3819 } 3820 3821 /* Merge backward if suitable */ 3822 if (start_pfn < early_node_map[i].end_pfn && 3823 end_pfn >= early_node_map[i].start_pfn) { 3824 early_node_map[i].start_pfn = start_pfn; 3825 return; 3826 } 3827 } 3828 3829 /* Check that early_node_map is large enough */ 3830 if (i >= MAX_ACTIVE_REGIONS) { 3831 printk(KERN_CRIT "More than %d memory regions, truncating\n", 3832 MAX_ACTIVE_REGIONS); 3833 return; 3834 } 3835 3836 early_node_map[i].nid = nid; 3837 early_node_map[i].start_pfn = start_pfn; 3838 early_node_map[i].end_pfn = end_pfn; 3839 nr_nodemap_entries = i + 1; 3840} 3841 3842/** 3843 * remove_active_range - Shrink an existing registered range of PFNs 3844 * @nid: The node id the range is on that should be shrunk 3845 * @start_pfn: The new PFN of the range 3846 * @end_pfn: The new PFN of the range 3847 * 3848 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node. 3849 * The map is kept near the end physical page range that has already been 3850 * registered. This function allows an arch to shrink an existing registered 3851 * range. 3852 */ 3853void __init remove_active_range(unsigned int nid, unsigned long start_pfn, 3854 unsigned long end_pfn) 3855{ 3856 int i, j; 3857 int removed = 0; 3858 3859 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n", 3860 nid, start_pfn, end_pfn); 3861 3862 /* Find the old active region end and shrink */ 3863 for_each_active_range_index_in_nid(i, nid) { 3864 if (early_node_map[i].start_pfn >= start_pfn && 3865 early_node_map[i].end_pfn <= end_pfn) { 3866 /* clear it */ 3867 early_node_map[i].start_pfn = 0; 3868 early_node_map[i].end_pfn = 0; 3869 removed = 1; 3870 continue; 3871 } 3872 if (early_node_map[i].start_pfn < start_pfn && 3873 early_node_map[i].end_pfn > start_pfn) { 3874 unsigned long temp_end_pfn = early_node_map[i].end_pfn; 3875 early_node_map[i].end_pfn = start_pfn; 3876 if (temp_end_pfn > end_pfn) 3877 add_active_range(nid, end_pfn, temp_end_pfn); 3878 continue; 3879 } 3880 if (early_node_map[i].start_pfn >= start_pfn && 3881 early_node_map[i].end_pfn > end_pfn && 3882 early_node_map[i].start_pfn < end_pfn) { 3883 early_node_map[i].start_pfn = end_pfn; 3884 continue; 3885 } 3886 } 3887 3888 if (!removed) 3889 return; 3890 3891 /* remove the blank ones */ 3892 for (i = nr_nodemap_entries - 1; i > 0; i--) { 3893 if (early_node_map[i].nid != nid) 3894 continue; 3895 if (early_node_map[i].end_pfn) 3896 continue; 3897 /* we found it, get rid of it */ 3898 for (j = i; j < nr_nodemap_entries - 1; j++) 3899 memcpy(&early_node_map[j], &early_node_map[j+1], 3900 sizeof(early_node_map[j])); 3901 j = nr_nodemap_entries - 1; 3902 memset(&early_node_map[j], 0, sizeof(early_node_map[j])); 3903 nr_nodemap_entries--; 3904 } 3905} 3906 3907/** 3908 * remove_all_active_ranges - Remove all currently registered regions 3909 * 3910 * During discovery, it may be found that a table like SRAT is invalid 3911 * and an alternative discovery method must be used. This function removes 3912 * all currently registered regions. 3913 */ 3914void __init remove_all_active_ranges(void) 3915{ 3916 memset(early_node_map, 0, sizeof(early_node_map)); 3917 nr_nodemap_entries = 0; 3918} 3919 3920/* Compare two active node_active_regions */ 3921static int __init cmp_node_active_region(const void *a, const void *b) 3922{ 3923 struct node_active_region *arange = (struct node_active_region *)a; 3924 struct node_active_region *brange = (struct node_active_region *)b; 3925 3926 /* Done this way to avoid overflows */ 3927 if (arange->start_pfn > brange->start_pfn) 3928 return 1; 3929 if (arange->start_pfn < brange->start_pfn) 3930 return -1; 3931 3932 return 0; 3933} 3934 3935/* sort the node_map by start_pfn */ 3936static void __init sort_node_map(void) 3937{ 3938 sort(early_node_map, (size_t)nr_nodemap_entries, 3939 sizeof(struct node_active_region), 3940 cmp_node_active_region, NULL); 3941} 3942 3943/* Find the lowest pfn for a node */ 3944static unsigned long __init find_min_pfn_for_node(int nid) 3945{ 3946 int i; 3947 unsigned long min_pfn = ULONG_MAX; 3948 3949 /* Assuming a sorted map, the first range found has the starting pfn */ 3950 for_each_active_range_index_in_nid(i, nid) 3951 min_pfn = min(min_pfn, early_node_map[i].start_pfn); 3952 3953 if (min_pfn == ULONG_MAX) { 3954 printk(KERN_WARNING 3955 "Could not find start_pfn for node %d\n", nid); 3956 return 0; 3957 } 3958 3959 return min_pfn; 3960} 3961 3962/** 3963 * find_min_pfn_with_active_regions - Find the minimum PFN registered 3964 * 3965 * It returns the minimum PFN based on information provided via 3966 * add_active_range(). 3967 */ 3968unsigned long __init find_min_pfn_with_active_regions(void) 3969{ 3970 return find_min_pfn_for_node(MAX_NUMNODES); 3971} 3972 3973/* 3974 * early_calculate_totalpages() 3975 * Sum pages in active regions for movable zone. 3976 * Populate N_HIGH_MEMORY for calculating usable_nodes. 3977 */ 3978static unsigned long __init early_calculate_totalpages(void) 3979{ 3980 int i; 3981 unsigned long totalpages = 0; 3982 3983 for (i = 0; i < nr_nodemap_entries; i++) { 3984 unsigned long pages = early_node_map[i].end_pfn - 3985 early_node_map[i].start_pfn; 3986 totalpages += pages; 3987 if (pages) 3988 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY); 3989 } 3990 return totalpages; 3991} 3992 3993/* 3994 * Find the PFN the Movable zone begins in each node. Kernel memory 3995 * is spread evenly between nodes as long as the nodes have enough 3996 * memory. When they don't, some nodes will have more kernelcore than 3997 * others 3998 */ 3999static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn) 4000{ 4001 int i, nid; 4002 unsigned long usable_startpfn; 4003 unsigned long kernelcore_node, kernelcore_remaining; 4004 unsigned long totalpages = early_calculate_totalpages(); 4005 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]); 4006 4007 /* 4008 * If movablecore was specified, calculate what size of 4009 * kernelcore that corresponds so that memory usable for 4010 * any allocation type is evenly spread. If both kernelcore 4011 * and movablecore are specified, then the value of kernelcore 4012 * will be used for required_kernelcore if it's greater than 4013 * what movablecore would have allowed. 4014 */ 4015 if (required_movablecore) { 4016 unsigned long corepages; 4017 4018 /* 4019 * Round-up so that ZONE_MOVABLE is at least as large as what 4020 * was requested by the user 4021 */ 4022 required_movablecore = 4023 roundup(required_movablecore, MAX_ORDER_NR_PAGES); 4024 corepages = totalpages - required_movablecore; 4025 4026 required_kernelcore = max(required_kernelcore, corepages); 4027 } 4028 4029 /* If kernelcore was not specified, there is no ZONE_MOVABLE */ 4030 if (!required_kernelcore) 4031 return; 4032 4033 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ 4034 find_usable_zone_for_movable(); 4035 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; 4036 4037restart: 4038 /* Spread kernelcore memory as evenly as possible throughout nodes */ 4039 kernelcore_node = required_kernelcore / usable_nodes; 4040 for_each_node_state(nid, N_HIGH_MEMORY) { 4041 /* 4042 * Recalculate kernelcore_node if the division per node 4043 * now exceeds what is necessary to satisfy the requested 4044 * amount of memory for the kernel 4045 */ 4046 if (required_kernelcore < kernelcore_node) 4047 kernelcore_node = required_kernelcore / usable_nodes; 4048 4049 /* 4050 * As the map is walked, we track how much memory is usable 4051 * by the kernel using kernelcore_remaining. When it is 4052 * 0, the rest of the node is usable by ZONE_MOVABLE 4053 */ 4054 kernelcore_remaining = kernelcore_node; 4055 4056 /* Go through each range of PFNs within this node */ 4057 for_each_active_range_index_in_nid(i, nid) { 4058 unsigned long start_pfn, end_pfn; 4059 unsigned long size_pages; 4060 4061 start_pfn = max(early_node_map[i].start_pfn, 4062 zone_movable_pfn[nid]); 4063 end_pfn = early_node_map[i].end_pfn; 4064 if (start_pfn >= end_pfn) 4065 continue; 4066 4067 /* Account for what is only usable for kernelcore */ 4068 if (start_pfn < usable_startpfn) { 4069 unsigned long kernel_pages; 4070 kernel_pages = min(end_pfn, usable_startpfn) 4071 - start_pfn; 4072 4073 kernelcore_remaining -= min(kernel_pages, 4074 kernelcore_remaining); 4075 required_kernelcore -= min(kernel_pages, 4076 required_kernelcore); 4077 4078 /* Continue if range is now fully accounted */ 4079 if (end_pfn <= usable_startpfn) { 4080 4081 /* 4082 * Push zone_movable_pfn to the end so 4083 * that if we have to rebalance 4084 * kernelcore across nodes, we will 4085 * not double account here 4086 */ 4087 zone_movable_pfn[nid] = end_pfn; 4088 continue; 4089 } 4090 start_pfn = usable_startpfn; 4091 } 4092 4093 /* 4094 * The usable PFN range for ZONE_MOVABLE is from 4095 * start_pfn->end_pfn. Calculate size_pages as the 4096 * number of pages used as kernelcore 4097 */ 4098 size_pages = end_pfn - start_pfn; 4099 if (size_pages > kernelcore_remaining) 4100 size_pages = kernelcore_remaining; 4101 zone_movable_pfn[nid] = start_pfn + size_pages; 4102 4103 /* 4104 * Some kernelcore has been met, update counts and 4105 * break if the kernelcore for this node has been 4106 * satisified 4107 */ 4108 required_kernelcore -= min(required_kernelcore, 4109 size_pages); 4110 kernelcore_remaining -= size_pages; 4111 if (!kernelcore_remaining) 4112 break; 4113 } 4114 } 4115 4116 /* 4117 * If there is still required_kernelcore, we do another pass with one 4118 * less node in the count. This will push zone_movable_pfn[nid] further 4119 * along on the nodes that still have memory until kernelcore is 4120 * satisified 4121 */ 4122 usable_nodes--; 4123 if (usable_nodes && required_kernelcore > usable_nodes) 4124 goto restart; 4125 4126 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ 4127 for (nid = 0; nid < MAX_NUMNODES; nid++) 4128 zone_movable_pfn[nid] = 4129 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); 4130} 4131 4132/* Any regular memory on that node ? */ 4133static void check_for_regular_memory(pg_data_t *pgdat) 4134{ 4135#ifdef CONFIG_HIGHMEM 4136 enum zone_type zone_type; 4137 4138 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) { 4139 struct zone *zone = &pgdat->node_zones[zone_type]; 4140 if (zone->present_pages) 4141 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY); 4142 } 4143#endif 4144} 4145 4146/** 4147 * free_area_init_nodes - Initialise all pg_data_t and zone data 4148 * @max_zone_pfn: an array of max PFNs for each zone 4149 * 4150 * This will call free_area_init_node() for each active node in the system. 4151 * Using the page ranges provided by add_active_range(), the size of each 4152 * zone in each node and their holes is calculated. If the maximum PFN 4153 * between two adjacent zones match, it is assumed that the zone is empty. 4154 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed 4155 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone 4156 * starts where the previous one ended. For example, ZONE_DMA32 starts 4157 * at arch_max_dma_pfn. 4158 */ 4159void __init free_area_init_nodes(unsigned long *max_zone_pfn) 4160{ 4161 unsigned long nid; 4162 int i; 4163 4164 /* Sort early_node_map as initialisation assumes it is sorted */ 4165 sort_node_map(); 4166 4167 /* Record where the zone boundaries are */ 4168 memset(arch_zone_lowest_possible_pfn, 0, 4169 sizeof(arch_zone_lowest_possible_pfn)); 4170 memset(arch_zone_highest_possible_pfn, 0, 4171 sizeof(arch_zone_highest_possible_pfn)); 4172 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions(); 4173 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0]; 4174 for (i = 1; i < MAX_NR_ZONES; i++) { 4175 if (i == ZONE_MOVABLE) 4176 continue; 4177 arch_zone_lowest_possible_pfn[i] = 4178 arch_zone_highest_possible_pfn[i-1]; 4179 arch_zone_highest_possible_pfn[i] = 4180 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]); 4181 } 4182 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0; 4183 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0; 4184 4185 /* Find the PFNs that ZONE_MOVABLE begins at in each node */ 4186 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); 4187 find_zone_movable_pfns_for_nodes(zone_movable_pfn); 4188 4189 /* Print out the zone ranges */ 4190 printk("Zone PFN ranges:\n"); 4191 for (i = 0; i < MAX_NR_ZONES; i++) { 4192 if (i == ZONE_MOVABLE) 4193 continue; 4194 printk(" %-8s %0#10lx -> %0#10lx\n", 4195 zone_names[i], 4196 arch_zone_lowest_possible_pfn[i], 4197 arch_zone_highest_possible_pfn[i]); 4198 } 4199 4200 /* Print out the PFNs ZONE_MOVABLE begins at in each node */ 4201 printk("Movable zone start PFN for each node\n"); 4202 for (i = 0; i < MAX_NUMNODES; i++) { 4203 if (zone_movable_pfn[i]) 4204 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]); 4205 } 4206 4207 /* Print out the early_node_map[] */ 4208 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries); 4209 for (i = 0; i < nr_nodemap_entries; i++) 4210 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid, 4211 early_node_map[i].start_pfn, 4212 early_node_map[i].end_pfn); 4213 4214 /* Initialise every node */ 4215 mminit_verify_pageflags_layout(); 4216 setup_nr_node_ids(); 4217 for_each_online_node(nid) { 4218 pg_data_t *pgdat = NODE_DATA(nid); 4219 free_area_init_node(nid, NULL, 4220 find_min_pfn_for_node(nid), NULL); 4221 4222 /* Any memory on that node */ 4223 if (pgdat->node_present_pages) 4224 node_set_state(nid, N_HIGH_MEMORY); 4225 check_for_regular_memory(pgdat); 4226 } 4227} 4228 4229static int __init cmdline_parse_core(char *p, unsigned long *core) 4230{ 4231 unsigned long long coremem; 4232 if (!p) 4233 return -EINVAL; 4234 4235 coremem = memparse(p, &p); 4236 *core = coremem >> PAGE_SHIFT; 4237 4238 /* Paranoid check that UL is enough for the coremem value */ 4239 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); 4240 4241 return 0; 4242} 4243 4244/* 4245 * kernelcore=size sets the amount of memory for use for allocations that 4246 * cannot be reclaimed or migrated. 4247 */ 4248static int __init cmdline_parse_kernelcore(char *p) 4249{ 4250 return cmdline_parse_core(p, &required_kernelcore); 4251} 4252 4253/* 4254 * movablecore=size sets the amount of memory for use for allocations that 4255 * can be reclaimed or migrated. 4256 */ 4257static int __init cmdline_parse_movablecore(char *p) 4258{ 4259 return cmdline_parse_core(p, &required_movablecore); 4260} 4261 4262early_param("kernelcore", cmdline_parse_kernelcore); 4263early_param("movablecore", cmdline_parse_movablecore); 4264 4265#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 4266 4267/** 4268 * set_dma_reserve - set the specified number of pages reserved in the first zone 4269 * @new_dma_reserve: The number of pages to mark reserved 4270 * 4271 * The per-cpu batchsize and zone watermarks are determined by present_pages. 4272 * In the DMA zone, a significant percentage may be consumed by kernel image 4273 * and other unfreeable allocations which can skew the watermarks badly. This 4274 * function may optionally be used to account for unfreeable pages in the 4275 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and 4276 * smaller per-cpu batchsize. 4277 */ 4278void __init set_dma_reserve(unsigned long new_dma_reserve) 4279{ 4280 dma_reserve = new_dma_reserve; 4281} 4282 4283#ifndef CONFIG_NEED_MULTIPLE_NODES 4284struct pglist_data __refdata contig_page_data = { .bdata = &bootmem_node_data[0] }; 4285EXPORT_SYMBOL(contig_page_data); 4286#endif 4287 4288void __init free_area_init(unsigned long *zones_size) 4289{ 4290 free_area_init_node(0, zones_size, 4291 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); 4292} 4293 4294static int page_alloc_cpu_notify(struct notifier_block *self, 4295 unsigned long action, void *hcpu) 4296{ 4297 int cpu = (unsigned long)hcpu; 4298 4299 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) { 4300 drain_pages(cpu); 4301 4302 /* 4303 * Spill the event counters of the dead processor 4304 * into the current processors event counters. 4305 * This artificially elevates the count of the current 4306 * processor. 4307 */ 4308 vm_events_fold_cpu(cpu); 4309 4310 /* 4311 * Zero the differential counters of the dead processor 4312 * so that the vm statistics are consistent. 4313 * 4314 * This is only okay since the processor is dead and cannot 4315 * race with what we are doing. 4316 */ 4317 refresh_cpu_vm_stats(cpu); 4318 } 4319 return NOTIFY_OK; 4320} 4321 4322void __init page_alloc_init(void) 4323{ 4324 hotcpu_notifier(page_alloc_cpu_notify, 0); 4325} 4326 4327/* 4328 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio 4329 * or min_free_kbytes changes. 4330 */ 4331static void calculate_totalreserve_pages(void) 4332{ 4333 struct pglist_data *pgdat; 4334 unsigned long reserve_pages = 0; 4335 enum zone_type i, j; 4336 4337 for_each_online_pgdat(pgdat) { 4338 for (i = 0; i < MAX_NR_ZONES; i++) { 4339 struct zone *zone = pgdat->node_zones + i; 4340 unsigned long max = 0; 4341 4342 /* Find valid and maximum lowmem_reserve in the zone */ 4343 for (j = i; j < MAX_NR_ZONES; j++) { 4344 if (zone->lowmem_reserve[j] > max) 4345 max = zone->lowmem_reserve[j]; 4346 } 4347 4348 /* we treat the high watermark as reserved pages. */ 4349 max += high_wmark_pages(zone); 4350 4351 if (max > zone->present_pages) 4352 max = zone->present_pages; 4353 reserve_pages += max; 4354 } 4355 } 4356 totalreserve_pages = reserve_pages; 4357} 4358 4359/* 4360 * setup_per_zone_lowmem_reserve - called whenever 4361 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone 4362 * has a correct pages reserved value, so an adequate number of 4363 * pages are left in the zone after a successful __alloc_pages(). 4364 */ 4365static void setup_per_zone_lowmem_reserve(void) 4366{ 4367 struct pglist_data *pgdat; 4368 enum zone_type j, idx; 4369 4370 for_each_online_pgdat(pgdat) { 4371 for (j = 0; j < MAX_NR_ZONES; j++) { 4372 struct zone *zone = pgdat->node_zones + j; 4373 unsigned long present_pages = zone->present_pages; 4374 4375 zone->lowmem_reserve[j] = 0; 4376 4377 idx = j; 4378 while (idx) { 4379 struct zone *lower_zone; 4380 4381 idx--; 4382 4383 if (sysctl_lowmem_reserve_ratio[idx] < 1) 4384 sysctl_lowmem_reserve_ratio[idx] = 1; 4385 4386 lower_zone = pgdat->node_zones + idx; 4387 lower_zone->lowmem_reserve[j] = present_pages / 4388 sysctl_lowmem_reserve_ratio[idx]; 4389 present_pages += lower_zone->present_pages; 4390 } 4391 } 4392 } 4393 4394 /* update totalreserve_pages */ 4395 calculate_totalreserve_pages(); 4396} 4397 4398/** 4399 * setup_per_zone_pages_min - called when min_free_kbytes changes. 4400 * 4401 * Ensures that the pages_{min,low,high} values for each zone are set correctly 4402 * with respect to min_free_kbytes. 4403 */ 4404void setup_per_zone_pages_min(void) 4405{ 4406 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); 4407 unsigned long lowmem_pages = 0; 4408 struct zone *zone; 4409 unsigned long flags; 4410 4411 /* Calculate total number of !ZONE_HIGHMEM pages */ 4412 for_each_zone(zone) { 4413 if (!is_highmem(zone)) 4414 lowmem_pages += zone->present_pages; 4415 } 4416 4417 for_each_zone(zone) { 4418 u64 tmp; 4419 4420 spin_lock_irqsave(&zone->lock, flags); 4421 tmp = (u64)pages_min * zone->present_pages; 4422 do_div(tmp, lowmem_pages); 4423 if (is_highmem(zone)) { 4424 /* 4425 * __GFP_HIGH and PF_MEMALLOC allocations usually don't 4426 * need highmem pages, so cap pages_min to a small 4427 * value here. 4428 * 4429 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN) 4430 * deltas controls asynch page reclaim, and so should 4431 * not be capped for highmem. 4432 */ 4433 int min_pages; 4434 4435 min_pages = zone->present_pages / 1024; 4436 if (min_pages < SWAP_CLUSTER_MAX) 4437 min_pages = SWAP_CLUSTER_MAX; 4438 if (min_pages > 128) 4439 min_pages = 128; 4440 zone->watermark[WMARK_MIN] = min_pages; 4441 } else { 4442 /* 4443 * If it's a lowmem zone, reserve a number of pages 4444 * proportionate to the zone's size. 4445 */ 4446 zone->watermark[WMARK_MIN] = tmp; 4447 } 4448 4449 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2); 4450 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1); 4451 setup_zone_migrate_reserve(zone); 4452 spin_unlock_irqrestore(&zone->lock, flags); 4453 } 4454 4455 /* update totalreserve_pages */ 4456 calculate_totalreserve_pages(); 4457} 4458 4459/** 4460 * The inactive anon list should be small enough that the VM never has to 4461 * do too much work, but large enough that each inactive page has a chance 4462 * to be referenced again before it is swapped out. 4463 * 4464 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to 4465 * INACTIVE_ANON pages on this zone's LRU, maintained by the 4466 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of 4467 * the anonymous pages are kept on the inactive list. 4468 * 4469 * total target max 4470 * memory ratio inactive anon 4471 * ------------------------------------- 4472 * 10MB 1 5MB 4473 * 100MB 1 50MB 4474 * 1GB 3 250MB 4475 * 10GB 10 0.9GB 4476 * 100GB 31 3GB 4477 * 1TB 101 10GB 4478 * 10TB 320 32GB 4479 */ 4480static void __init setup_per_zone_inactive_ratio(void) 4481{ 4482 struct zone *zone; 4483 4484 for_each_zone(zone) { 4485 unsigned int gb, ratio; 4486 4487 /* Zone size in gigabytes */ 4488 gb = zone->present_pages >> (30 - PAGE_SHIFT); 4489 if (gb) 4490 ratio = int_sqrt(10 * gb); 4491 else 4492 ratio = 1; 4493 4494 zone->inactive_ratio = ratio; 4495 } 4496} 4497 4498/* 4499 * Initialise min_free_kbytes. 4500 * 4501 * For small machines we want it small (128k min). For large machines 4502 * we want it large (64MB max). But it is not linear, because network 4503 * bandwidth does not increase linearly with machine size. We use 4504 * 4505 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: 4506 * min_free_kbytes = sqrt(lowmem_kbytes * 16) 4507 * 4508 * which yields 4509 * 4510 * 16MB: 512k 4511 * 32MB: 724k 4512 * 64MB: 1024k 4513 * 128MB: 1448k 4514 * 256MB: 2048k 4515 * 512MB: 2896k 4516 * 1024MB: 4096k 4517 * 2048MB: 5792k 4518 * 4096MB: 8192k 4519 * 8192MB: 11584k 4520 * 16384MB: 16384k 4521 */ 4522static int __init init_per_zone_pages_min(void) 4523{ 4524 unsigned long lowmem_kbytes; 4525 4526 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); 4527 4528 min_free_kbytes = int_sqrt(lowmem_kbytes * 16); 4529 if (min_free_kbytes < 128) 4530 min_free_kbytes = 128; 4531 if (min_free_kbytes > 65536) 4532 min_free_kbytes = 65536; 4533 setup_per_zone_pages_min(); 4534 setup_per_zone_lowmem_reserve(); 4535 setup_per_zone_inactive_ratio(); 4536 return 0; 4537} 4538module_init(init_per_zone_pages_min) 4539 4540/* 4541 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so 4542 * that we can call two helper functions whenever min_free_kbytes 4543 * changes. 4544 */ 4545int min_free_kbytes_sysctl_handler(ctl_table *table, int write, 4546 struct file *file, void __user *buffer, size_t *length, loff_t *ppos) 4547{ 4548 proc_dointvec(table, write, file, buffer, length, ppos); 4549 if (write) 4550 setup_per_zone_pages_min(); 4551 return 0; 4552} 4553 4554#ifdef CONFIG_NUMA 4555int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write, 4556 struct file *file, void __user *buffer, size_t *length, loff_t *ppos) 4557{ 4558 struct zone *zone; 4559 int rc; 4560 4561 rc = proc_dointvec_minmax(table, write, file, buffer, length, ppos); 4562 if (rc) 4563 return rc; 4564 4565 for_each_zone(zone) 4566 zone->min_unmapped_pages = (zone->present_pages * 4567 sysctl_min_unmapped_ratio) / 100; 4568 return 0; 4569} 4570 4571int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write, 4572 struct file *file, void __user *buffer, size_t *length, loff_t *ppos) 4573{ 4574 struct zone *zone; 4575 int rc; 4576 4577 rc = proc_dointvec_minmax(table, write, file, buffer, length, ppos); 4578 if (rc) 4579 return rc; 4580 4581 for_each_zone(zone) 4582 zone->min_slab_pages = (zone->present_pages * 4583 sysctl_min_slab_ratio) / 100; 4584 return 0; 4585} 4586#endif 4587 4588/* 4589 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around 4590 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() 4591 * whenever sysctl_lowmem_reserve_ratio changes. 4592 * 4593 * The reserve ratio obviously has absolutely no relation with the 4594 * minimum watermarks. The lowmem reserve ratio can only make sense 4595 * if in function of the boot time zone sizes. 4596 */ 4597int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, 4598 struct file *file, void __user *buffer, size_t *length, loff_t *ppos) 4599{ 4600 proc_dointvec_minmax(table, write, file, buffer, length, ppos); 4601 setup_per_zone_lowmem_reserve(); 4602 return 0; 4603} 4604 4605/* 4606 * percpu_pagelist_fraction - changes the pcp->high for each zone on each 4607 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist 4608 * can have before it gets flushed back to buddy allocator. 4609 */ 4610 4611int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write, 4612 struct file *file, void __user *buffer, size_t *length, loff_t *ppos) 4613{ 4614 struct zone *zone; 4615 unsigned int cpu; 4616 int ret; 4617 4618 ret = proc_dointvec_minmax(table, write, file, buffer, length, ppos); 4619 if (!write || (ret == -EINVAL)) 4620 return ret; 4621 for_each_zone(zone) { 4622 for_each_online_cpu(cpu) { 4623 unsigned long high; 4624 high = zone->present_pages / percpu_pagelist_fraction; 4625 setup_pagelist_highmark(zone_pcp(zone, cpu), high); 4626 } 4627 } 4628 return 0; 4629} 4630 4631int hashdist = HASHDIST_DEFAULT; 4632 4633#ifdef CONFIG_NUMA 4634static int __init set_hashdist(char *str) 4635{ 4636 if (!str) 4637 return 0; 4638 hashdist = simple_strtoul(str, &str, 0); 4639 return 1; 4640} 4641__setup("hashdist=", set_hashdist); 4642#endif 4643 4644/* 4645 * allocate a large system hash table from bootmem 4646 * - it is assumed that the hash table must contain an exact power-of-2 4647 * quantity of entries 4648 * - limit is the number of hash buckets, not the total allocation size 4649 */ 4650void *__init alloc_large_system_hash(const char *tablename, 4651 unsigned long bucketsize, 4652 unsigned long numentries, 4653 int scale, 4654 int flags, 4655 unsigned int *_hash_shift, 4656 unsigned int *_hash_mask, 4657 unsigned long limit) 4658{ 4659 unsigned long long max = limit; 4660 unsigned long log2qty, size; 4661 void *table = NULL; 4662 4663 /* allow the kernel cmdline to have a say */ 4664 if (!numentries) { 4665 /* round applicable memory size up to nearest megabyte */ 4666 numentries = nr_kernel_pages; 4667 numentries += (1UL << (20 - PAGE_SHIFT)) - 1; 4668 numentries >>= 20 - PAGE_SHIFT; 4669 numentries <<= 20 - PAGE_SHIFT; 4670 4671 /* limit to 1 bucket per 2^scale bytes of low memory */ 4672 if (scale > PAGE_SHIFT) 4673 numentries >>= (scale - PAGE_SHIFT); 4674 else 4675 numentries <<= (PAGE_SHIFT - scale); 4676 4677 /* Make sure we've got at least a 0-order allocation.. */ 4678 if (unlikely((numentries * bucketsize) < PAGE_SIZE)) 4679 numentries = PAGE_SIZE / bucketsize; 4680 } 4681 numentries = roundup_pow_of_two(numentries); 4682 4683 /* limit allocation size to 1/16 total memory by default */ 4684 if (max == 0) { 4685 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; 4686 do_div(max, bucketsize); 4687 } 4688 4689 if (numentries > max) 4690 numentries = max; 4691 4692 log2qty = ilog2(numentries); 4693 4694 do { 4695 size = bucketsize << log2qty; 4696 if (flags & HASH_EARLY) 4697 table = alloc_bootmem_nopanic(size); 4698 else if (hashdist) 4699 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); 4700 else { 4701 /* 4702 * If bucketsize is not a power-of-two, we may free 4703 * some pages at the end of hash table which 4704 * alloc_pages_exact() automatically does 4705 */ 4706 if (get_order(size) < MAX_ORDER) 4707 table = alloc_pages_exact(size, GFP_ATOMIC); 4708 } 4709 } while (!table && size > PAGE_SIZE && --log2qty); 4710 4711 if (!table) 4712 panic("Failed to allocate %s hash table\n", tablename); 4713 4714 printk(KERN_INFO "%s hash table entries: %d (order: %d, %lu bytes)\n", 4715 tablename, 4716 (1U << log2qty), 4717 ilog2(size) - PAGE_SHIFT, 4718 size); 4719 4720 if (_hash_shift) 4721 *_hash_shift = log2qty; 4722 if (_hash_mask) 4723 *_hash_mask = (1 << log2qty) - 1; 4724 4725 /* 4726 * If hashdist is set, the table allocation is done with __vmalloc() 4727 * which invokes the kmemleak_alloc() callback. This function may also 4728 * be called before the slab and kmemleak are initialised when 4729 * kmemleak simply buffers the request to be executed later 4730 * (GFP_ATOMIC flag ignored in this case). 4731 */ 4732 if (!hashdist) 4733 kmemleak_alloc(table, size, 1, GFP_ATOMIC); 4734 4735 return table; 4736} 4737 4738/* Return a pointer to the bitmap storing bits affecting a block of pages */ 4739static inline unsigned long *get_pageblock_bitmap(struct zone *zone, 4740 unsigned long pfn) 4741{ 4742#ifdef CONFIG_SPARSEMEM 4743 return __pfn_to_section(pfn)->pageblock_flags; 4744#else 4745 return zone->pageblock_flags; 4746#endif /* CONFIG_SPARSEMEM */ 4747} 4748 4749static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn) 4750{ 4751#ifdef CONFIG_SPARSEMEM 4752 pfn &= (PAGES_PER_SECTION-1); 4753 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; 4754#else 4755 pfn = pfn - zone->zone_start_pfn; 4756 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; 4757#endif /* CONFIG_SPARSEMEM */ 4758} 4759 4760/** 4761 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages 4762 * @page: The page within the block of interest 4763 * @start_bitidx: The first bit of interest to retrieve 4764 * @end_bitidx: The last bit of interest 4765 * returns pageblock_bits flags 4766 */ 4767unsigned long get_pageblock_flags_group(struct page *page, 4768 int start_bitidx, int end_bitidx) 4769{ 4770 struct zone *zone; 4771 unsigned long *bitmap; 4772 unsigned long pfn, bitidx; 4773 unsigned long flags = 0; 4774 unsigned long value = 1; 4775 4776 zone = page_zone(page); 4777 pfn = page_to_pfn(page); 4778 bitmap = get_pageblock_bitmap(zone, pfn); 4779 bitidx = pfn_to_bitidx(zone, pfn); 4780 4781 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) 4782 if (test_bit(bitidx + start_bitidx, bitmap)) 4783 flags |= value; 4784 4785 return flags; 4786} 4787 4788/** 4789 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages 4790 * @page: The page within the block of interest 4791 * @start_bitidx: The first bit of interest 4792 * @end_bitidx: The last bit of interest 4793 * @flags: The flags to set 4794 */ 4795void set_pageblock_flags_group(struct page *page, unsigned long flags, 4796 int start_bitidx, int end_bitidx) 4797{ 4798 struct zone *zone; 4799 unsigned long *bitmap; 4800 unsigned long pfn, bitidx; 4801 unsigned long value = 1; 4802 4803 zone = page_zone(page); 4804 pfn = page_to_pfn(page); 4805 bitmap = get_pageblock_bitmap(zone, pfn); 4806 bitidx = pfn_to_bitidx(zone, pfn); 4807 VM_BUG_ON(pfn < zone->zone_start_pfn); 4808 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages); 4809 4810 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) 4811 if (flags & value) 4812 __set_bit(bitidx + start_bitidx, bitmap); 4813 else 4814 __clear_bit(bitidx + start_bitidx, bitmap); 4815} 4816 4817/* 4818 * This is designed as sub function...plz see page_isolation.c also. 4819 * set/clear page block's type to be ISOLATE. 4820 * page allocater never alloc memory from ISOLATE block. 4821 */ 4822 4823int set_migratetype_isolate(struct page *page) 4824{ 4825 struct zone *zone; 4826 unsigned long flags; 4827 int ret = -EBUSY; 4828 4829 zone = page_zone(page); 4830 spin_lock_irqsave(&zone->lock, flags); 4831 /* 4832 * In future, more migrate types will be able to be isolation target. 4833 */ 4834 if (get_pageblock_migratetype(page) != MIGRATE_MOVABLE) 4835 goto out; 4836 set_pageblock_migratetype(page, MIGRATE_ISOLATE); 4837 move_freepages_block(zone, page, MIGRATE_ISOLATE); 4838 ret = 0; 4839out: 4840 spin_unlock_irqrestore(&zone->lock, flags); 4841 if (!ret) 4842 drain_all_pages(); 4843 return ret; 4844} 4845 4846void unset_migratetype_isolate(struct page *page) 4847{ 4848 struct zone *zone; 4849 unsigned long flags; 4850 zone = page_zone(page); 4851 spin_lock_irqsave(&zone->lock, flags); 4852 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE) 4853 goto out; 4854 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 4855 move_freepages_block(zone, page, MIGRATE_MOVABLE); 4856out: 4857 spin_unlock_irqrestore(&zone->lock, flags); 4858} 4859 4860#ifdef CONFIG_MEMORY_HOTREMOVE 4861/* 4862 * All pages in the range must be isolated before calling this. 4863 */ 4864void 4865__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) 4866{ 4867 struct page *page; 4868 struct zone *zone; 4869 int order, i; 4870 unsigned long pfn; 4871 unsigned long flags; 4872 /* find the first valid pfn */ 4873 for (pfn = start_pfn; pfn < end_pfn; pfn++) 4874 if (pfn_valid(pfn)) 4875 break; 4876 if (pfn == end_pfn) 4877 return; 4878 zone = page_zone(pfn_to_page(pfn)); 4879 spin_lock_irqsave(&zone->lock, flags); 4880 pfn = start_pfn; 4881 while (pfn < end_pfn) { 4882 if (!pfn_valid(pfn)) { 4883 pfn++; 4884 continue; 4885 } 4886 page = pfn_to_page(pfn); 4887 BUG_ON(page_count(page)); 4888 BUG_ON(!PageBuddy(page)); 4889 order = page_order(page); 4890#ifdef CONFIG_DEBUG_VM 4891 printk(KERN_INFO "remove from free list %lx %d %lx\n", 4892 pfn, 1 << order, end_pfn); 4893#endif 4894 list_del(&page->lru); 4895 rmv_page_order(page); 4896 zone->free_area[order].nr_free--; 4897 __mod_zone_page_state(zone, NR_FREE_PAGES, 4898 - (1UL << order)); 4899 for (i = 0; i < (1 << order); i++) 4900 SetPageReserved((page+i)); 4901 pfn += (1 << order); 4902 } 4903 spin_unlock_irqrestore(&zone->lock, flags); 4904} 4905#endif 4906