page_alloc.c revision 4f92e2586b43a2402e116055d4edda704f911b5b
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/kmemcheck.h> 27#include <linux/module.h> 28#include <linux/suspend.h> 29#include <linux/pagevec.h> 30#include <linux/blkdev.h> 31#include <linux/slab.h> 32#include <linux/oom.h> 33#include <linux/notifier.h> 34#include <linux/topology.h> 35#include <linux/sysctl.h> 36#include <linux/cpu.h> 37#include <linux/cpuset.h> 38#include <linux/memory_hotplug.h> 39#include <linux/nodemask.h> 40#include <linux/vmalloc.h> 41#include <linux/mempolicy.h> 42#include <linux/stop_machine.h> 43#include <linux/sort.h> 44#include <linux/pfn.h> 45#include <linux/backing-dev.h> 46#include <linux/fault-inject.h> 47#include <linux/page-isolation.h> 48#include <linux/page_cgroup.h> 49#include <linux/debugobjects.h> 50#include <linux/kmemleak.h> 51#include <linux/memory.h> 52#include <linux/compaction.h> 53#include <trace/events/kmem.h> 54#include <linux/ftrace_event.h> 55 56#include <asm/tlbflush.h> 57#include <asm/div64.h> 58#include "internal.h" 59 60/* 61 * Array of node states. 62 */ 63nodemask_t node_states[NR_NODE_STATES] __read_mostly = { 64 [N_POSSIBLE] = NODE_MASK_ALL, 65 [N_ONLINE] = { { [0] = 1UL } }, 66#ifndef CONFIG_NUMA 67 [N_NORMAL_MEMORY] = { { [0] = 1UL } }, 68#ifdef CONFIG_HIGHMEM 69 [N_HIGH_MEMORY] = { { [0] = 1UL } }, 70#endif 71 [N_CPU] = { { [0] = 1UL } }, 72#endif /* NUMA */ 73}; 74EXPORT_SYMBOL(node_states); 75 76unsigned long totalram_pages __read_mostly; 77unsigned long totalreserve_pages __read_mostly; 78int percpu_pagelist_fraction; 79gfp_t gfp_allowed_mask __read_mostly = GFP_BOOT_MASK; 80 81#ifdef CONFIG_PM_SLEEP 82/* 83 * The following functions are used by the suspend/hibernate code to temporarily 84 * change gfp_allowed_mask in order to avoid using I/O during memory allocations 85 * while devices are suspended. To avoid races with the suspend/hibernate code, 86 * they should always be called with pm_mutex held (gfp_allowed_mask also should 87 * only be modified with pm_mutex held, unless the suspend/hibernate code is 88 * guaranteed not to run in parallel with that modification). 89 */ 90void set_gfp_allowed_mask(gfp_t mask) 91{ 92 WARN_ON(!mutex_is_locked(&pm_mutex)); 93 gfp_allowed_mask = mask; 94} 95 96gfp_t clear_gfp_allowed_mask(gfp_t mask) 97{ 98 gfp_t ret = gfp_allowed_mask; 99 100 WARN_ON(!mutex_is_locked(&pm_mutex)); 101 gfp_allowed_mask &= ~mask; 102 return ret; 103} 104#endif /* CONFIG_PM_SLEEP */ 105 106#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE 107int pageblock_order __read_mostly; 108#endif 109 110static void __free_pages_ok(struct page *page, unsigned int order); 111 112/* 113 * results with 256, 32 in the lowmem_reserve sysctl: 114 * 1G machine -> (16M dma, 800M-16M normal, 1G-800M high) 115 * 1G machine -> (16M dma, 784M normal, 224M high) 116 * NORMAL allocation will leave 784M/256 of ram reserved in the ZONE_DMA 117 * HIGHMEM allocation will leave 224M/32 of ram reserved in ZONE_NORMAL 118 * HIGHMEM allocation will (224M+784M)/256 of ram reserved in ZONE_DMA 119 * 120 * TBD: should special case ZONE_DMA32 machines here - in those we normally 121 * don't need any ZONE_NORMAL reservation 122 */ 123int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = { 124#ifdef CONFIG_ZONE_DMA 125 256, 126#endif 127#ifdef CONFIG_ZONE_DMA32 128 256, 129#endif 130#ifdef CONFIG_HIGHMEM 131 32, 132#endif 133 32, 134}; 135 136EXPORT_SYMBOL(totalram_pages); 137 138static char * const zone_names[MAX_NR_ZONES] = { 139#ifdef CONFIG_ZONE_DMA 140 "DMA", 141#endif 142#ifdef CONFIG_ZONE_DMA32 143 "DMA32", 144#endif 145 "Normal", 146#ifdef CONFIG_HIGHMEM 147 "HighMem", 148#endif 149 "Movable", 150}; 151 152int min_free_kbytes = 1024; 153 154static unsigned long __meminitdata nr_kernel_pages; 155static unsigned long __meminitdata nr_all_pages; 156static unsigned long __meminitdata dma_reserve; 157 158#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 159 /* 160 * MAX_ACTIVE_REGIONS determines the maximum number of distinct 161 * ranges of memory (RAM) that may be registered with add_active_range(). 162 * Ranges passed to add_active_range() will be merged if possible 163 * so the number of times add_active_range() can be called is 164 * related to the number of nodes and the number of holes 165 */ 166 #ifdef CONFIG_MAX_ACTIVE_REGIONS 167 /* Allow an architecture to set MAX_ACTIVE_REGIONS to save memory */ 168 #define MAX_ACTIVE_REGIONS CONFIG_MAX_ACTIVE_REGIONS 169 #else 170 #if MAX_NUMNODES >= 32 171 /* If there can be many nodes, allow up to 50 holes per node */ 172 #define MAX_ACTIVE_REGIONS (MAX_NUMNODES*50) 173 #else 174 /* By default, allow up to 256 distinct regions */ 175 #define MAX_ACTIVE_REGIONS 256 176 #endif 177 #endif 178 179 static struct node_active_region __meminitdata early_node_map[MAX_ACTIVE_REGIONS]; 180 static int __meminitdata nr_nodemap_entries; 181 static unsigned long __meminitdata arch_zone_lowest_possible_pfn[MAX_NR_ZONES]; 182 static unsigned long __meminitdata arch_zone_highest_possible_pfn[MAX_NR_ZONES]; 183 static unsigned long __initdata required_kernelcore; 184 static unsigned long __initdata required_movablecore; 185 static unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES]; 186 187 /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */ 188 int movable_zone; 189 EXPORT_SYMBOL(movable_zone); 190#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 191 192#if MAX_NUMNODES > 1 193int nr_node_ids __read_mostly = MAX_NUMNODES; 194int nr_online_nodes __read_mostly = 1; 195EXPORT_SYMBOL(nr_node_ids); 196EXPORT_SYMBOL(nr_online_nodes); 197#endif 198 199int page_group_by_mobility_disabled __read_mostly; 200 201static void set_pageblock_migratetype(struct page *page, int migratetype) 202{ 203 204 if (unlikely(page_group_by_mobility_disabled)) 205 migratetype = MIGRATE_UNMOVABLE; 206 207 set_pageblock_flags_group(page, (unsigned long)migratetype, 208 PB_migrate, PB_migrate_end); 209} 210 211bool oom_killer_disabled __read_mostly; 212 213#ifdef CONFIG_DEBUG_VM 214static int page_outside_zone_boundaries(struct zone *zone, struct page *page) 215{ 216 int ret = 0; 217 unsigned seq; 218 unsigned long pfn = page_to_pfn(page); 219 220 do { 221 seq = zone_span_seqbegin(zone); 222 if (pfn >= zone->zone_start_pfn + zone->spanned_pages) 223 ret = 1; 224 else if (pfn < zone->zone_start_pfn) 225 ret = 1; 226 } while (zone_span_seqretry(zone, seq)); 227 228 return ret; 229} 230 231static int page_is_consistent(struct zone *zone, struct page *page) 232{ 233 if (!pfn_valid_within(page_to_pfn(page))) 234 return 0; 235 if (zone != page_zone(page)) 236 return 0; 237 238 return 1; 239} 240/* 241 * Temporary debugging check for pages not lying within a given zone. 242 */ 243static int bad_range(struct zone *zone, struct page *page) 244{ 245 if (page_outside_zone_boundaries(zone, page)) 246 return 1; 247 if (!page_is_consistent(zone, page)) 248 return 1; 249 250 return 0; 251} 252#else 253static inline int bad_range(struct zone *zone, struct page *page) 254{ 255 return 0; 256} 257#endif 258 259static void bad_page(struct page *page) 260{ 261 static unsigned long resume; 262 static unsigned long nr_shown; 263 static unsigned long nr_unshown; 264 265 /* Don't complain about poisoned pages */ 266 if (PageHWPoison(page)) { 267 __ClearPageBuddy(page); 268 return; 269 } 270 271 /* 272 * Allow a burst of 60 reports, then keep quiet for that minute; 273 * or allow a steady drip of one report per second. 274 */ 275 if (nr_shown == 60) { 276 if (time_before(jiffies, resume)) { 277 nr_unshown++; 278 goto out; 279 } 280 if (nr_unshown) { 281 printk(KERN_ALERT 282 "BUG: Bad page state: %lu messages suppressed\n", 283 nr_unshown); 284 nr_unshown = 0; 285 } 286 nr_shown = 0; 287 } 288 if (nr_shown++ == 0) 289 resume = jiffies + 60 * HZ; 290 291 printk(KERN_ALERT "BUG: Bad page state in process %s pfn:%05lx\n", 292 current->comm, page_to_pfn(page)); 293 dump_page(page); 294 295 dump_stack(); 296out: 297 /* Leave bad fields for debug, except PageBuddy could make trouble */ 298 __ClearPageBuddy(page); 299 add_taint(TAINT_BAD_PAGE); 300} 301 302/* 303 * Higher-order pages are called "compound pages". They are structured thusly: 304 * 305 * The first PAGE_SIZE page is called the "head page". 306 * 307 * The remaining PAGE_SIZE pages are called "tail pages". 308 * 309 * All pages have PG_compound set. All pages have their ->private pointing at 310 * the head page (even the head page has this). 311 * 312 * The first tail page's ->lru.next holds the address of the compound page's 313 * put_page() function. Its ->lru.prev holds the order of allocation. 314 * This usage means that zero-order pages may not be compound. 315 */ 316 317static void free_compound_page(struct page *page) 318{ 319 __free_pages_ok(page, compound_order(page)); 320} 321 322void prep_compound_page(struct page *page, unsigned long order) 323{ 324 int i; 325 int nr_pages = 1 << order; 326 327 set_compound_page_dtor(page, free_compound_page); 328 set_compound_order(page, order); 329 __SetPageHead(page); 330 for (i = 1; i < nr_pages; i++) { 331 struct page *p = page + i; 332 333 __SetPageTail(p); 334 p->first_page = page; 335 } 336} 337 338static int destroy_compound_page(struct page *page, unsigned long order) 339{ 340 int i; 341 int nr_pages = 1 << order; 342 int bad = 0; 343 344 if (unlikely(compound_order(page) != order) || 345 unlikely(!PageHead(page))) { 346 bad_page(page); 347 bad++; 348 } 349 350 __ClearPageHead(page); 351 352 for (i = 1; i < nr_pages; i++) { 353 struct page *p = page + i; 354 355 if (unlikely(!PageTail(p) || (p->first_page != page))) { 356 bad_page(page); 357 bad++; 358 } 359 __ClearPageTail(p); 360 } 361 362 return bad; 363} 364 365static inline void prep_zero_page(struct page *page, int order, gfp_t gfp_flags) 366{ 367 int i; 368 369 /* 370 * clear_highpage() will use KM_USER0, so it's a bug to use __GFP_ZERO 371 * and __GFP_HIGHMEM from hard or soft interrupt context. 372 */ 373 VM_BUG_ON((gfp_flags & __GFP_HIGHMEM) && in_interrupt()); 374 for (i = 0; i < (1 << order); i++) 375 clear_highpage(page + i); 376} 377 378static inline void set_page_order(struct page *page, int order) 379{ 380 set_page_private(page, order); 381 __SetPageBuddy(page); 382} 383 384static inline void rmv_page_order(struct page *page) 385{ 386 __ClearPageBuddy(page); 387 set_page_private(page, 0); 388} 389 390/* 391 * Locate the struct page for both the matching buddy in our 392 * pair (buddy1) and the combined O(n+1) page they form (page). 393 * 394 * 1) Any buddy B1 will have an order O twin B2 which satisfies 395 * the following equation: 396 * B2 = B1 ^ (1 << O) 397 * For example, if the starting buddy (buddy2) is #8 its order 398 * 1 buddy is #10: 399 * B2 = 8 ^ (1 << 1) = 8 ^ 2 = 10 400 * 401 * 2) Any buddy B will have an order O+1 parent P which 402 * satisfies the following equation: 403 * P = B & ~(1 << O) 404 * 405 * Assumption: *_mem_map is contiguous at least up to MAX_ORDER 406 */ 407static inline struct page * 408__page_find_buddy(struct page *page, unsigned long page_idx, unsigned int order) 409{ 410 unsigned long buddy_idx = page_idx ^ (1 << order); 411 412 return page + (buddy_idx - page_idx); 413} 414 415static inline unsigned long 416__find_combined_index(unsigned long page_idx, unsigned int order) 417{ 418 return (page_idx & ~(1 << order)); 419} 420 421/* 422 * This function checks whether a page is free && is the buddy 423 * we can do coalesce a page and its buddy if 424 * (a) the buddy is not in a hole && 425 * (b) the buddy is in the buddy system && 426 * (c) a page and its buddy have the same order && 427 * (d) a page and its buddy are in the same zone. 428 * 429 * For recording whether a page is in the buddy system, we use PG_buddy. 430 * Setting, clearing, and testing PG_buddy is serialized by zone->lock. 431 * 432 * For recording page's order, we use page_private(page). 433 */ 434static inline int page_is_buddy(struct page *page, struct page *buddy, 435 int order) 436{ 437 if (!pfn_valid_within(page_to_pfn(buddy))) 438 return 0; 439 440 if (page_zone_id(page) != page_zone_id(buddy)) 441 return 0; 442 443 if (PageBuddy(buddy) && page_order(buddy) == order) { 444 VM_BUG_ON(page_count(buddy) != 0); 445 return 1; 446 } 447 return 0; 448} 449 450/* 451 * Freeing function for a buddy system allocator. 452 * 453 * The concept of a buddy system is to maintain direct-mapped table 454 * (containing bit values) for memory blocks of various "orders". 455 * The bottom level table contains the map for the smallest allocatable 456 * units of memory (here, pages), and each level above it describes 457 * pairs of units from the levels below, hence, "buddies". 458 * At a high level, all that happens here is marking the table entry 459 * at the bottom level available, and propagating the changes upward 460 * as necessary, plus some accounting needed to play nicely with other 461 * parts of the VM system. 462 * At each level, we keep a list of pages, which are heads of continuous 463 * free pages of length of (1 << order) and marked with PG_buddy. Page's 464 * order is recorded in page_private(page) field. 465 * So when we are allocating or freeing one, we can derive the state of the 466 * other. That is, if we allocate a small block, and both were 467 * free, the remainder of the region must be split into blocks. 468 * If a block is freed, and its buddy is also free, then this 469 * triggers coalescing into a block of larger size. 470 * 471 * -- wli 472 */ 473 474static inline void __free_one_page(struct page *page, 475 struct zone *zone, unsigned int order, 476 int migratetype) 477{ 478 unsigned long page_idx; 479 unsigned long combined_idx; 480 struct page *buddy; 481 482 if (unlikely(PageCompound(page))) 483 if (unlikely(destroy_compound_page(page, order))) 484 return; 485 486 VM_BUG_ON(migratetype == -1); 487 488 page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1); 489 490 VM_BUG_ON(page_idx & ((1 << order) - 1)); 491 VM_BUG_ON(bad_range(zone, page)); 492 493 while (order < MAX_ORDER-1) { 494 buddy = __page_find_buddy(page, page_idx, order); 495 if (!page_is_buddy(page, buddy, order)) 496 break; 497 498 /* Our buddy is free, merge with it and move up one order. */ 499 list_del(&buddy->lru); 500 zone->free_area[order].nr_free--; 501 rmv_page_order(buddy); 502 combined_idx = __find_combined_index(page_idx, order); 503 page = page + (combined_idx - page_idx); 504 page_idx = combined_idx; 505 order++; 506 } 507 set_page_order(page, order); 508 509 /* 510 * If this is not the largest possible page, check if the buddy 511 * of the next-highest order is free. If it is, it's possible 512 * that pages are being freed that will coalesce soon. In case, 513 * that is happening, add the free page to the tail of the list 514 * so it's less likely to be used soon and more likely to be merged 515 * as a higher order page 516 */ 517 if ((order < MAX_ORDER-1) && pfn_valid_within(page_to_pfn(buddy))) { 518 struct page *higher_page, *higher_buddy; 519 combined_idx = __find_combined_index(page_idx, order); 520 higher_page = page + combined_idx - page_idx; 521 higher_buddy = __page_find_buddy(higher_page, combined_idx, order + 1); 522 if (page_is_buddy(higher_page, higher_buddy, order + 1)) { 523 list_add_tail(&page->lru, 524 &zone->free_area[order].free_list[migratetype]); 525 goto out; 526 } 527 } 528 529 list_add(&page->lru, &zone->free_area[order].free_list[migratetype]); 530out: 531 zone->free_area[order].nr_free++; 532} 533 534/* 535 * free_page_mlock() -- clean up attempts to free and mlocked() page. 536 * Page should not be on lru, so no need to fix that up. 537 * free_pages_check() will verify... 538 */ 539static inline void free_page_mlock(struct page *page) 540{ 541 __dec_zone_page_state(page, NR_MLOCK); 542 __count_vm_event(UNEVICTABLE_MLOCKFREED); 543} 544 545static inline int free_pages_check(struct page *page) 546{ 547 if (unlikely(page_mapcount(page) | 548 (page->mapping != NULL) | 549 (atomic_read(&page->_count) != 0) | 550 (page->flags & PAGE_FLAGS_CHECK_AT_FREE))) { 551 bad_page(page); 552 return 1; 553 } 554 if (page->flags & PAGE_FLAGS_CHECK_AT_PREP) 555 page->flags &= ~PAGE_FLAGS_CHECK_AT_PREP; 556 return 0; 557} 558 559/* 560 * Frees a number of pages from the PCP lists 561 * Assumes all pages on list are in same zone, and of same order. 562 * count is the number of pages to free. 563 * 564 * If the zone was previously in an "all pages pinned" state then look to 565 * see if this freeing clears that state. 566 * 567 * And clear the zone's pages_scanned counter, to hold off the "all pages are 568 * pinned" detection logic. 569 */ 570static void free_pcppages_bulk(struct zone *zone, int count, 571 struct per_cpu_pages *pcp) 572{ 573 int migratetype = 0; 574 int batch_free = 0; 575 576 spin_lock(&zone->lock); 577 zone->all_unreclaimable = 0; 578 zone->pages_scanned = 0; 579 580 __mod_zone_page_state(zone, NR_FREE_PAGES, count); 581 while (count) { 582 struct page *page; 583 struct list_head *list; 584 585 /* 586 * Remove pages from lists in a round-robin fashion. A 587 * batch_free count is maintained that is incremented when an 588 * empty list is encountered. This is so more pages are freed 589 * off fuller lists instead of spinning excessively around empty 590 * lists 591 */ 592 do { 593 batch_free++; 594 if (++migratetype == MIGRATE_PCPTYPES) 595 migratetype = 0; 596 list = &pcp->lists[migratetype]; 597 } while (list_empty(list)); 598 599 do { 600 page = list_entry(list->prev, struct page, lru); 601 /* must delete as __free_one_page list manipulates */ 602 list_del(&page->lru); 603 /* MIGRATE_MOVABLE list may include MIGRATE_RESERVEs */ 604 __free_one_page(page, zone, 0, page_private(page)); 605 trace_mm_page_pcpu_drain(page, 0, page_private(page)); 606 } while (--count && --batch_free && !list_empty(list)); 607 } 608 spin_unlock(&zone->lock); 609} 610 611static void free_one_page(struct zone *zone, struct page *page, int order, 612 int migratetype) 613{ 614 spin_lock(&zone->lock); 615 zone->all_unreclaimable = 0; 616 zone->pages_scanned = 0; 617 618 __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order); 619 __free_one_page(page, zone, order, migratetype); 620 spin_unlock(&zone->lock); 621} 622 623static void __free_pages_ok(struct page *page, unsigned int order) 624{ 625 unsigned long flags; 626 int i; 627 int bad = 0; 628 int wasMlocked = __TestClearPageMlocked(page); 629 630 trace_mm_page_free_direct(page, order); 631 kmemcheck_free_shadow(page, order); 632 633 for (i = 0 ; i < (1 << order) ; ++i) 634 bad += free_pages_check(page + i); 635 if (bad) 636 return; 637 638 if (!PageHighMem(page)) { 639 debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order); 640 debug_check_no_obj_freed(page_address(page), 641 PAGE_SIZE << order); 642 } 643 arch_free_page(page, order); 644 kernel_map_pages(page, 1 << order, 0); 645 646 local_irq_save(flags); 647 if (unlikely(wasMlocked)) 648 free_page_mlock(page); 649 __count_vm_events(PGFREE, 1 << order); 650 free_one_page(page_zone(page), page, order, 651 get_pageblock_migratetype(page)); 652 local_irq_restore(flags); 653} 654 655/* 656 * permit the bootmem allocator to evade page validation on high-order frees 657 */ 658void __meminit __free_pages_bootmem(struct page *page, unsigned int order) 659{ 660 if (order == 0) { 661 __ClearPageReserved(page); 662 set_page_count(page, 0); 663 set_page_refcounted(page); 664 __free_page(page); 665 } else { 666 int loop; 667 668 prefetchw(page); 669 for (loop = 0; loop < BITS_PER_LONG; loop++) { 670 struct page *p = &page[loop]; 671 672 if (loop + 1 < BITS_PER_LONG) 673 prefetchw(p + 1); 674 __ClearPageReserved(p); 675 set_page_count(p, 0); 676 } 677 678 set_page_refcounted(page); 679 __free_pages(page, order); 680 } 681} 682 683 684/* 685 * The order of subdivision here is critical for the IO subsystem. 686 * Please do not alter this order without good reasons and regression 687 * testing. Specifically, as large blocks of memory are subdivided, 688 * the order in which smaller blocks are delivered depends on the order 689 * they're subdivided in this function. This is the primary factor 690 * influencing the order in which pages are delivered to the IO 691 * subsystem according to empirical testing, and this is also justified 692 * by considering the behavior of a buddy system containing a single 693 * large block of memory acted on by a series of small allocations. 694 * This behavior is a critical factor in sglist merging's success. 695 * 696 * -- wli 697 */ 698static inline void expand(struct zone *zone, struct page *page, 699 int low, int high, struct free_area *area, 700 int migratetype) 701{ 702 unsigned long size = 1 << high; 703 704 while (high > low) { 705 area--; 706 high--; 707 size >>= 1; 708 VM_BUG_ON(bad_range(zone, &page[size])); 709 list_add(&page[size].lru, &area->free_list[migratetype]); 710 area->nr_free++; 711 set_page_order(&page[size], high); 712 } 713} 714 715/* 716 * This page is about to be returned from the page allocator 717 */ 718static inline int check_new_page(struct page *page) 719{ 720 if (unlikely(page_mapcount(page) | 721 (page->mapping != NULL) | 722 (atomic_read(&page->_count) != 0) | 723 (page->flags & PAGE_FLAGS_CHECK_AT_PREP))) { 724 bad_page(page); 725 return 1; 726 } 727 return 0; 728} 729 730static int prep_new_page(struct page *page, int order, gfp_t gfp_flags) 731{ 732 int i; 733 734 for (i = 0; i < (1 << order); i++) { 735 struct page *p = page + i; 736 if (unlikely(check_new_page(p))) 737 return 1; 738 } 739 740 set_page_private(page, 0); 741 set_page_refcounted(page); 742 743 arch_alloc_page(page, order); 744 kernel_map_pages(page, 1 << order, 1); 745 746 if (gfp_flags & __GFP_ZERO) 747 prep_zero_page(page, order, gfp_flags); 748 749 if (order && (gfp_flags & __GFP_COMP)) 750 prep_compound_page(page, order); 751 752 return 0; 753} 754 755/* 756 * Go through the free lists for the given migratetype and remove 757 * the smallest available page from the freelists 758 */ 759static inline 760struct page *__rmqueue_smallest(struct zone *zone, unsigned int order, 761 int migratetype) 762{ 763 unsigned int current_order; 764 struct free_area * area; 765 struct page *page; 766 767 /* Find a page of the appropriate size in the preferred list */ 768 for (current_order = order; current_order < MAX_ORDER; ++current_order) { 769 area = &(zone->free_area[current_order]); 770 if (list_empty(&area->free_list[migratetype])) 771 continue; 772 773 page = list_entry(area->free_list[migratetype].next, 774 struct page, lru); 775 list_del(&page->lru); 776 rmv_page_order(page); 777 area->nr_free--; 778 expand(zone, page, order, current_order, area, migratetype); 779 return page; 780 } 781 782 return NULL; 783} 784 785 786/* 787 * This array describes the order lists are fallen back to when 788 * the free lists for the desirable migrate type are depleted 789 */ 790static int fallbacks[MIGRATE_TYPES][MIGRATE_TYPES-1] = { 791 [MIGRATE_UNMOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, 792 [MIGRATE_RECLAIMABLE] = { MIGRATE_UNMOVABLE, MIGRATE_MOVABLE, MIGRATE_RESERVE }, 793 [MIGRATE_MOVABLE] = { MIGRATE_RECLAIMABLE, MIGRATE_UNMOVABLE, MIGRATE_RESERVE }, 794 [MIGRATE_RESERVE] = { MIGRATE_RESERVE, MIGRATE_RESERVE, MIGRATE_RESERVE }, /* Never used */ 795}; 796 797/* 798 * Move the free pages in a range to the free lists of the requested type. 799 * Note that start_page and end_pages are not aligned on a pageblock 800 * boundary. If alignment is required, use move_freepages_block() 801 */ 802static int move_freepages(struct zone *zone, 803 struct page *start_page, struct page *end_page, 804 int migratetype) 805{ 806 struct page *page; 807 unsigned long order; 808 int pages_moved = 0; 809 810#ifndef CONFIG_HOLES_IN_ZONE 811 /* 812 * page_zone is not safe to call in this context when 813 * CONFIG_HOLES_IN_ZONE is set. This bug check is probably redundant 814 * anyway as we check zone boundaries in move_freepages_block(). 815 * Remove at a later date when no bug reports exist related to 816 * grouping pages by mobility 817 */ 818 BUG_ON(page_zone(start_page) != page_zone(end_page)); 819#endif 820 821 for (page = start_page; page <= end_page;) { 822 /* Make sure we are not inadvertently changing nodes */ 823 VM_BUG_ON(page_to_nid(page) != zone_to_nid(zone)); 824 825 if (!pfn_valid_within(page_to_pfn(page))) { 826 page++; 827 continue; 828 } 829 830 if (!PageBuddy(page)) { 831 page++; 832 continue; 833 } 834 835 order = page_order(page); 836 list_del(&page->lru); 837 list_add(&page->lru, 838 &zone->free_area[order].free_list[migratetype]); 839 page += 1 << order; 840 pages_moved += 1 << order; 841 } 842 843 return pages_moved; 844} 845 846static int move_freepages_block(struct zone *zone, struct page *page, 847 int migratetype) 848{ 849 unsigned long start_pfn, end_pfn; 850 struct page *start_page, *end_page; 851 852 start_pfn = page_to_pfn(page); 853 start_pfn = start_pfn & ~(pageblock_nr_pages-1); 854 start_page = pfn_to_page(start_pfn); 855 end_page = start_page + pageblock_nr_pages - 1; 856 end_pfn = start_pfn + pageblock_nr_pages - 1; 857 858 /* Do not cross zone boundaries */ 859 if (start_pfn < zone->zone_start_pfn) 860 start_page = page; 861 if (end_pfn >= zone->zone_start_pfn + zone->spanned_pages) 862 return 0; 863 864 return move_freepages(zone, start_page, end_page, migratetype); 865} 866 867static void change_pageblock_range(struct page *pageblock_page, 868 int start_order, int migratetype) 869{ 870 int nr_pageblocks = 1 << (start_order - pageblock_order); 871 872 while (nr_pageblocks--) { 873 set_pageblock_migratetype(pageblock_page, migratetype); 874 pageblock_page += pageblock_nr_pages; 875 } 876} 877 878/* Remove an element from the buddy allocator from the fallback list */ 879static inline struct page * 880__rmqueue_fallback(struct zone *zone, int order, int start_migratetype) 881{ 882 struct free_area * area; 883 int current_order; 884 struct page *page; 885 int migratetype, i; 886 887 /* Find the largest possible block of pages in the other list */ 888 for (current_order = MAX_ORDER-1; current_order >= order; 889 --current_order) { 890 for (i = 0; i < MIGRATE_TYPES - 1; i++) { 891 migratetype = fallbacks[start_migratetype][i]; 892 893 /* MIGRATE_RESERVE handled later if necessary */ 894 if (migratetype == MIGRATE_RESERVE) 895 continue; 896 897 area = &(zone->free_area[current_order]); 898 if (list_empty(&area->free_list[migratetype])) 899 continue; 900 901 page = list_entry(area->free_list[migratetype].next, 902 struct page, lru); 903 area->nr_free--; 904 905 /* 906 * If breaking a large block of pages, move all free 907 * pages to the preferred allocation list. If falling 908 * back for a reclaimable kernel allocation, be more 909 * agressive about taking ownership of free pages 910 */ 911 if (unlikely(current_order >= (pageblock_order >> 1)) || 912 start_migratetype == MIGRATE_RECLAIMABLE || 913 page_group_by_mobility_disabled) { 914 unsigned long pages; 915 pages = move_freepages_block(zone, page, 916 start_migratetype); 917 918 /* Claim the whole block if over half of it is free */ 919 if (pages >= (1 << (pageblock_order-1)) || 920 page_group_by_mobility_disabled) 921 set_pageblock_migratetype(page, 922 start_migratetype); 923 924 migratetype = start_migratetype; 925 } 926 927 /* Remove the page from the freelists */ 928 list_del(&page->lru); 929 rmv_page_order(page); 930 931 /* Take ownership for orders >= pageblock_order */ 932 if (current_order >= pageblock_order) 933 change_pageblock_range(page, current_order, 934 start_migratetype); 935 936 expand(zone, page, order, current_order, area, migratetype); 937 938 trace_mm_page_alloc_extfrag(page, order, current_order, 939 start_migratetype, migratetype); 940 941 return page; 942 } 943 } 944 945 return NULL; 946} 947 948/* 949 * Do the hard work of removing an element from the buddy allocator. 950 * Call me with the zone->lock already held. 951 */ 952static struct page *__rmqueue(struct zone *zone, unsigned int order, 953 int migratetype) 954{ 955 struct page *page; 956 957retry_reserve: 958 page = __rmqueue_smallest(zone, order, migratetype); 959 960 if (unlikely(!page) && migratetype != MIGRATE_RESERVE) { 961 page = __rmqueue_fallback(zone, order, migratetype); 962 963 /* 964 * Use MIGRATE_RESERVE rather than fail an allocation. goto 965 * is used because __rmqueue_smallest is an inline function 966 * and we want just one call site 967 */ 968 if (!page) { 969 migratetype = MIGRATE_RESERVE; 970 goto retry_reserve; 971 } 972 } 973 974 trace_mm_page_alloc_zone_locked(page, order, migratetype); 975 return page; 976} 977 978/* 979 * Obtain a specified number of elements from the buddy allocator, all under 980 * a single hold of the lock, for efficiency. Add them to the supplied list. 981 * Returns the number of new pages which were placed at *list. 982 */ 983static int rmqueue_bulk(struct zone *zone, unsigned int order, 984 unsigned long count, struct list_head *list, 985 int migratetype, int cold) 986{ 987 int i; 988 989 spin_lock(&zone->lock); 990 for (i = 0; i < count; ++i) { 991 struct page *page = __rmqueue(zone, order, migratetype); 992 if (unlikely(page == NULL)) 993 break; 994 995 /* 996 * Split buddy pages returned by expand() are received here 997 * in physical page order. The page is added to the callers and 998 * list and the list head then moves forward. From the callers 999 * perspective, the linked list is ordered by page number in 1000 * some conditions. This is useful for IO devices that can 1001 * merge IO requests if the physical pages are ordered 1002 * properly. 1003 */ 1004 if (likely(cold == 0)) 1005 list_add(&page->lru, list); 1006 else 1007 list_add_tail(&page->lru, list); 1008 set_page_private(page, migratetype); 1009 list = &page->lru; 1010 } 1011 __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order)); 1012 spin_unlock(&zone->lock); 1013 return i; 1014} 1015 1016#ifdef CONFIG_NUMA 1017/* 1018 * Called from the vmstat counter updater to drain pagesets of this 1019 * currently executing processor on remote nodes after they have 1020 * expired. 1021 * 1022 * Note that this function must be called with the thread pinned to 1023 * a single processor. 1024 */ 1025void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp) 1026{ 1027 unsigned long flags; 1028 int to_drain; 1029 1030 local_irq_save(flags); 1031 if (pcp->count >= pcp->batch) 1032 to_drain = pcp->batch; 1033 else 1034 to_drain = pcp->count; 1035 free_pcppages_bulk(zone, to_drain, pcp); 1036 pcp->count -= to_drain; 1037 local_irq_restore(flags); 1038} 1039#endif 1040 1041/* 1042 * Drain pages of the indicated processor. 1043 * 1044 * The processor must either be the current processor and the 1045 * thread pinned to the current processor or a processor that 1046 * is not online. 1047 */ 1048static void drain_pages(unsigned int cpu) 1049{ 1050 unsigned long flags; 1051 struct zone *zone; 1052 1053 for_each_populated_zone(zone) { 1054 struct per_cpu_pageset *pset; 1055 struct per_cpu_pages *pcp; 1056 1057 local_irq_save(flags); 1058 pset = per_cpu_ptr(zone->pageset, cpu); 1059 1060 pcp = &pset->pcp; 1061 free_pcppages_bulk(zone, pcp->count, pcp); 1062 pcp->count = 0; 1063 local_irq_restore(flags); 1064 } 1065} 1066 1067/* 1068 * Spill all of this CPU's per-cpu pages back into the buddy allocator. 1069 */ 1070void drain_local_pages(void *arg) 1071{ 1072 drain_pages(smp_processor_id()); 1073} 1074 1075/* 1076 * Spill all the per-cpu pages from all CPUs back into the buddy allocator 1077 */ 1078void drain_all_pages(void) 1079{ 1080 on_each_cpu(drain_local_pages, NULL, 1); 1081} 1082 1083#ifdef CONFIG_HIBERNATION 1084 1085void mark_free_pages(struct zone *zone) 1086{ 1087 unsigned long pfn, max_zone_pfn; 1088 unsigned long flags; 1089 int order, t; 1090 struct list_head *curr; 1091 1092 if (!zone->spanned_pages) 1093 return; 1094 1095 spin_lock_irqsave(&zone->lock, flags); 1096 1097 max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages; 1098 for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++) 1099 if (pfn_valid(pfn)) { 1100 struct page *page = pfn_to_page(pfn); 1101 1102 if (!swsusp_page_is_forbidden(page)) 1103 swsusp_unset_page_free(page); 1104 } 1105 1106 for_each_migratetype_order(order, t) { 1107 list_for_each(curr, &zone->free_area[order].free_list[t]) { 1108 unsigned long i; 1109 1110 pfn = page_to_pfn(list_entry(curr, struct page, lru)); 1111 for (i = 0; i < (1UL << order); i++) 1112 swsusp_set_page_free(pfn_to_page(pfn + i)); 1113 } 1114 } 1115 spin_unlock_irqrestore(&zone->lock, flags); 1116} 1117#endif /* CONFIG_PM */ 1118 1119/* 1120 * Free a 0-order page 1121 * cold == 1 ? free a cold page : free a hot page 1122 */ 1123void free_hot_cold_page(struct page *page, int cold) 1124{ 1125 struct zone *zone = page_zone(page); 1126 struct per_cpu_pages *pcp; 1127 unsigned long flags; 1128 int migratetype; 1129 int wasMlocked = __TestClearPageMlocked(page); 1130 1131 trace_mm_page_free_direct(page, 0); 1132 kmemcheck_free_shadow(page, 0); 1133 1134 if (PageAnon(page)) 1135 page->mapping = NULL; 1136 if (free_pages_check(page)) 1137 return; 1138 1139 if (!PageHighMem(page)) { 1140 debug_check_no_locks_freed(page_address(page), PAGE_SIZE); 1141 debug_check_no_obj_freed(page_address(page), PAGE_SIZE); 1142 } 1143 arch_free_page(page, 0); 1144 kernel_map_pages(page, 1, 0); 1145 1146 migratetype = get_pageblock_migratetype(page); 1147 set_page_private(page, migratetype); 1148 local_irq_save(flags); 1149 if (unlikely(wasMlocked)) 1150 free_page_mlock(page); 1151 __count_vm_event(PGFREE); 1152 1153 /* 1154 * We only track unmovable, reclaimable and movable on pcp lists. 1155 * Free ISOLATE pages back to the allocator because they are being 1156 * offlined but treat RESERVE as movable pages so we can get those 1157 * areas back if necessary. Otherwise, we may have to free 1158 * excessively into the page allocator 1159 */ 1160 if (migratetype >= MIGRATE_PCPTYPES) { 1161 if (unlikely(migratetype == MIGRATE_ISOLATE)) { 1162 free_one_page(zone, page, 0, migratetype); 1163 goto out; 1164 } 1165 migratetype = MIGRATE_MOVABLE; 1166 } 1167 1168 pcp = &this_cpu_ptr(zone->pageset)->pcp; 1169 if (cold) 1170 list_add_tail(&page->lru, &pcp->lists[migratetype]); 1171 else 1172 list_add(&page->lru, &pcp->lists[migratetype]); 1173 pcp->count++; 1174 if (pcp->count >= pcp->high) { 1175 free_pcppages_bulk(zone, pcp->batch, pcp); 1176 pcp->count -= pcp->batch; 1177 } 1178 1179out: 1180 local_irq_restore(flags); 1181} 1182 1183/* 1184 * split_page takes a non-compound higher-order page, and splits it into 1185 * n (1<<order) sub-pages: page[0..n] 1186 * Each sub-page must be freed individually. 1187 * 1188 * Note: this is probably too low level an operation for use in drivers. 1189 * Please consult with lkml before using this in your driver. 1190 */ 1191void split_page(struct page *page, unsigned int order) 1192{ 1193 int i; 1194 1195 VM_BUG_ON(PageCompound(page)); 1196 VM_BUG_ON(!page_count(page)); 1197 1198#ifdef CONFIG_KMEMCHECK 1199 /* 1200 * Split shadow pages too, because free(page[0]) would 1201 * otherwise free the whole shadow. 1202 */ 1203 if (kmemcheck_page_is_tracked(page)) 1204 split_page(virt_to_page(page[0].shadow), order); 1205#endif 1206 1207 for (i = 1; i < (1 << order); i++) 1208 set_page_refcounted(page + i); 1209} 1210 1211/* 1212 * Similar to split_page except the page is already free. As this is only 1213 * being used for migration, the migratetype of the block also changes. 1214 * As this is called with interrupts disabled, the caller is responsible 1215 * for calling arch_alloc_page() and kernel_map_page() after interrupts 1216 * are enabled. 1217 * 1218 * Note: this is probably too low level an operation for use in drivers. 1219 * Please consult with lkml before using this in your driver. 1220 */ 1221int split_free_page(struct page *page) 1222{ 1223 unsigned int order; 1224 unsigned long watermark; 1225 struct zone *zone; 1226 1227 BUG_ON(!PageBuddy(page)); 1228 1229 zone = page_zone(page); 1230 order = page_order(page); 1231 1232 /* Obey watermarks as if the page was being allocated */ 1233 watermark = low_wmark_pages(zone) + (1 << order); 1234 if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) 1235 return 0; 1236 1237 /* Remove page from free list */ 1238 list_del(&page->lru); 1239 zone->free_area[order].nr_free--; 1240 rmv_page_order(page); 1241 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order)); 1242 1243 /* Split into individual pages */ 1244 set_page_refcounted(page); 1245 split_page(page, order); 1246 1247 if (order >= pageblock_order - 1) { 1248 struct page *endpage = page + (1 << order) - 1; 1249 for (; page < endpage; page += pageblock_nr_pages) 1250 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 1251 } 1252 1253 return 1 << order; 1254} 1255 1256/* 1257 * Really, prep_compound_page() should be called from __rmqueue_bulk(). But 1258 * we cheat by calling it from here, in the order > 0 path. Saves a branch 1259 * or two. 1260 */ 1261static inline 1262struct page *buffered_rmqueue(struct zone *preferred_zone, 1263 struct zone *zone, int order, gfp_t gfp_flags, 1264 int migratetype) 1265{ 1266 unsigned long flags; 1267 struct page *page; 1268 int cold = !!(gfp_flags & __GFP_COLD); 1269 1270again: 1271 if (likely(order == 0)) { 1272 struct per_cpu_pages *pcp; 1273 struct list_head *list; 1274 1275 local_irq_save(flags); 1276 pcp = &this_cpu_ptr(zone->pageset)->pcp; 1277 list = &pcp->lists[migratetype]; 1278 if (list_empty(list)) { 1279 pcp->count += rmqueue_bulk(zone, 0, 1280 pcp->batch, list, 1281 migratetype, cold); 1282 if (unlikely(list_empty(list))) 1283 goto failed; 1284 } 1285 1286 if (cold) 1287 page = list_entry(list->prev, struct page, lru); 1288 else 1289 page = list_entry(list->next, struct page, lru); 1290 1291 list_del(&page->lru); 1292 pcp->count--; 1293 } else { 1294 if (unlikely(gfp_flags & __GFP_NOFAIL)) { 1295 /* 1296 * __GFP_NOFAIL is not to be used in new code. 1297 * 1298 * All __GFP_NOFAIL callers should be fixed so that they 1299 * properly detect and handle allocation failures. 1300 * 1301 * We most definitely don't want callers attempting to 1302 * allocate greater than order-1 page units with 1303 * __GFP_NOFAIL. 1304 */ 1305 WARN_ON_ONCE(order > 1); 1306 } 1307 spin_lock_irqsave(&zone->lock, flags); 1308 page = __rmqueue(zone, order, migratetype); 1309 spin_unlock(&zone->lock); 1310 if (!page) 1311 goto failed; 1312 __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order)); 1313 } 1314 1315 __count_zone_vm_events(PGALLOC, zone, 1 << order); 1316 zone_statistics(preferred_zone, zone); 1317 local_irq_restore(flags); 1318 1319 VM_BUG_ON(bad_range(zone, page)); 1320 if (prep_new_page(page, order, gfp_flags)) 1321 goto again; 1322 return page; 1323 1324failed: 1325 local_irq_restore(flags); 1326 return NULL; 1327} 1328 1329/* The ALLOC_WMARK bits are used as an index to zone->watermark */ 1330#define ALLOC_WMARK_MIN WMARK_MIN 1331#define ALLOC_WMARK_LOW WMARK_LOW 1332#define ALLOC_WMARK_HIGH WMARK_HIGH 1333#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */ 1334 1335/* Mask to get the watermark bits */ 1336#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1) 1337 1338#define ALLOC_HARDER 0x10 /* try to alloc harder */ 1339#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */ 1340#define ALLOC_CPUSET 0x40 /* check for correct cpuset */ 1341 1342#ifdef CONFIG_FAIL_PAGE_ALLOC 1343 1344static struct fail_page_alloc_attr { 1345 struct fault_attr attr; 1346 1347 u32 ignore_gfp_highmem; 1348 u32 ignore_gfp_wait; 1349 u32 min_order; 1350 1351#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS 1352 1353 struct dentry *ignore_gfp_highmem_file; 1354 struct dentry *ignore_gfp_wait_file; 1355 struct dentry *min_order_file; 1356 1357#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ 1358 1359} fail_page_alloc = { 1360 .attr = FAULT_ATTR_INITIALIZER, 1361 .ignore_gfp_wait = 1, 1362 .ignore_gfp_highmem = 1, 1363 .min_order = 1, 1364}; 1365 1366static int __init setup_fail_page_alloc(char *str) 1367{ 1368 return setup_fault_attr(&fail_page_alloc.attr, str); 1369} 1370__setup("fail_page_alloc=", setup_fail_page_alloc); 1371 1372static int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) 1373{ 1374 if (order < fail_page_alloc.min_order) 1375 return 0; 1376 if (gfp_mask & __GFP_NOFAIL) 1377 return 0; 1378 if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM)) 1379 return 0; 1380 if (fail_page_alloc.ignore_gfp_wait && (gfp_mask & __GFP_WAIT)) 1381 return 0; 1382 1383 return should_fail(&fail_page_alloc.attr, 1 << order); 1384} 1385 1386#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS 1387 1388static int __init fail_page_alloc_debugfs(void) 1389{ 1390 mode_t mode = S_IFREG | S_IRUSR | S_IWUSR; 1391 struct dentry *dir; 1392 int err; 1393 1394 err = init_fault_attr_dentries(&fail_page_alloc.attr, 1395 "fail_page_alloc"); 1396 if (err) 1397 return err; 1398 dir = fail_page_alloc.attr.dentries.dir; 1399 1400 fail_page_alloc.ignore_gfp_wait_file = 1401 debugfs_create_bool("ignore-gfp-wait", mode, dir, 1402 &fail_page_alloc.ignore_gfp_wait); 1403 1404 fail_page_alloc.ignore_gfp_highmem_file = 1405 debugfs_create_bool("ignore-gfp-highmem", mode, dir, 1406 &fail_page_alloc.ignore_gfp_highmem); 1407 fail_page_alloc.min_order_file = 1408 debugfs_create_u32("min-order", mode, dir, 1409 &fail_page_alloc.min_order); 1410 1411 if (!fail_page_alloc.ignore_gfp_wait_file || 1412 !fail_page_alloc.ignore_gfp_highmem_file || 1413 !fail_page_alloc.min_order_file) { 1414 err = -ENOMEM; 1415 debugfs_remove(fail_page_alloc.ignore_gfp_wait_file); 1416 debugfs_remove(fail_page_alloc.ignore_gfp_highmem_file); 1417 debugfs_remove(fail_page_alloc.min_order_file); 1418 cleanup_fault_attr_dentries(&fail_page_alloc.attr); 1419 } 1420 1421 return err; 1422} 1423 1424late_initcall(fail_page_alloc_debugfs); 1425 1426#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */ 1427 1428#else /* CONFIG_FAIL_PAGE_ALLOC */ 1429 1430static inline int should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) 1431{ 1432 return 0; 1433} 1434 1435#endif /* CONFIG_FAIL_PAGE_ALLOC */ 1436 1437/* 1438 * Return 1 if free pages are above 'mark'. This takes into account the order 1439 * of the allocation. 1440 */ 1441int zone_watermark_ok(struct zone *z, int order, unsigned long mark, 1442 int classzone_idx, int alloc_flags) 1443{ 1444 /* free_pages my go negative - that's OK */ 1445 long min = mark; 1446 long free_pages = zone_page_state(z, NR_FREE_PAGES) - (1 << order) + 1; 1447 int o; 1448 1449 if (alloc_flags & ALLOC_HIGH) 1450 min -= min / 2; 1451 if (alloc_flags & ALLOC_HARDER) 1452 min -= min / 4; 1453 1454 if (free_pages <= min + z->lowmem_reserve[classzone_idx]) 1455 return 0; 1456 for (o = 0; o < order; o++) { 1457 /* At the next order, this order's pages become unavailable */ 1458 free_pages -= z->free_area[o].nr_free << o; 1459 1460 /* Require fewer higher order pages to be free */ 1461 min >>= 1; 1462 1463 if (free_pages <= min) 1464 return 0; 1465 } 1466 return 1; 1467} 1468 1469#ifdef CONFIG_NUMA 1470/* 1471 * zlc_setup - Setup for "zonelist cache". Uses cached zone data to 1472 * skip over zones that are not allowed by the cpuset, or that have 1473 * been recently (in last second) found to be nearly full. See further 1474 * comments in mmzone.h. Reduces cache footprint of zonelist scans 1475 * that have to skip over a lot of full or unallowed zones. 1476 * 1477 * If the zonelist cache is present in the passed in zonelist, then 1478 * returns a pointer to the allowed node mask (either the current 1479 * tasks mems_allowed, or node_states[N_HIGH_MEMORY].) 1480 * 1481 * If the zonelist cache is not available for this zonelist, does 1482 * nothing and returns NULL. 1483 * 1484 * If the fullzones BITMAP in the zonelist cache is stale (more than 1485 * a second since last zap'd) then we zap it out (clear its bits.) 1486 * 1487 * We hold off even calling zlc_setup, until after we've checked the 1488 * first zone in the zonelist, on the theory that most allocations will 1489 * be satisfied from that first zone, so best to examine that zone as 1490 * quickly as we can. 1491 */ 1492static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) 1493{ 1494 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1495 nodemask_t *allowednodes; /* zonelist_cache approximation */ 1496 1497 zlc = zonelist->zlcache_ptr; 1498 if (!zlc) 1499 return NULL; 1500 1501 if (time_after(jiffies, zlc->last_full_zap + HZ)) { 1502 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); 1503 zlc->last_full_zap = jiffies; 1504 } 1505 1506 allowednodes = !in_interrupt() && (alloc_flags & ALLOC_CPUSET) ? 1507 &cpuset_current_mems_allowed : 1508 &node_states[N_HIGH_MEMORY]; 1509 return allowednodes; 1510} 1511 1512/* 1513 * Given 'z' scanning a zonelist, run a couple of quick checks to see 1514 * if it is worth looking at further for free memory: 1515 * 1) Check that the zone isn't thought to be full (doesn't have its 1516 * bit set in the zonelist_cache fullzones BITMAP). 1517 * 2) Check that the zones node (obtained from the zonelist_cache 1518 * z_to_n[] mapping) is allowed in the passed in allowednodes mask. 1519 * Return true (non-zero) if zone is worth looking at further, or 1520 * else return false (zero) if it is not. 1521 * 1522 * This check -ignores- the distinction between various watermarks, 1523 * such as GFP_HIGH, GFP_ATOMIC, PF_MEMALLOC, ... If a zone is 1524 * found to be full for any variation of these watermarks, it will 1525 * be considered full for up to one second by all requests, unless 1526 * we are so low on memory on all allowed nodes that we are forced 1527 * into the second scan of the zonelist. 1528 * 1529 * In the second scan we ignore this zonelist cache and exactly 1530 * apply the watermarks to all zones, even it is slower to do so. 1531 * We are low on memory in the second scan, and should leave no stone 1532 * unturned looking for a free page. 1533 */ 1534static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, 1535 nodemask_t *allowednodes) 1536{ 1537 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1538 int i; /* index of *z in zonelist zones */ 1539 int n; /* node that zone *z is on */ 1540 1541 zlc = zonelist->zlcache_ptr; 1542 if (!zlc) 1543 return 1; 1544 1545 i = z - zonelist->_zonerefs; 1546 n = zlc->z_to_n[i]; 1547 1548 /* This zone is worth trying if it is allowed but not full */ 1549 return node_isset(n, *allowednodes) && !test_bit(i, zlc->fullzones); 1550} 1551 1552/* 1553 * Given 'z' scanning a zonelist, set the corresponding bit in 1554 * zlc->fullzones, so that subsequent attempts to allocate a page 1555 * from that zone don't waste time re-examining it. 1556 */ 1557static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) 1558{ 1559 struct zonelist_cache *zlc; /* cached zonelist speedup info */ 1560 int i; /* index of *z in zonelist zones */ 1561 1562 zlc = zonelist->zlcache_ptr; 1563 if (!zlc) 1564 return; 1565 1566 i = z - zonelist->_zonerefs; 1567 1568 set_bit(i, zlc->fullzones); 1569} 1570 1571#else /* CONFIG_NUMA */ 1572 1573static nodemask_t *zlc_setup(struct zonelist *zonelist, int alloc_flags) 1574{ 1575 return NULL; 1576} 1577 1578static int zlc_zone_worth_trying(struct zonelist *zonelist, struct zoneref *z, 1579 nodemask_t *allowednodes) 1580{ 1581 return 1; 1582} 1583 1584static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z) 1585{ 1586} 1587#endif /* CONFIG_NUMA */ 1588 1589/* 1590 * get_page_from_freelist goes through the zonelist trying to allocate 1591 * a page. 1592 */ 1593static struct page * 1594get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order, 1595 struct zonelist *zonelist, int high_zoneidx, int alloc_flags, 1596 struct zone *preferred_zone, int migratetype) 1597{ 1598 struct zoneref *z; 1599 struct page *page = NULL; 1600 int classzone_idx; 1601 struct zone *zone; 1602 nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */ 1603 int zlc_active = 0; /* set if using zonelist_cache */ 1604 int did_zlc_setup = 0; /* just call zlc_setup() one time */ 1605 1606 classzone_idx = zone_idx(preferred_zone); 1607zonelist_scan: 1608 /* 1609 * Scan zonelist, looking for a zone with enough free. 1610 * See also cpuset_zone_allowed() comment in kernel/cpuset.c. 1611 */ 1612 for_each_zone_zonelist_nodemask(zone, z, zonelist, 1613 high_zoneidx, nodemask) { 1614 if (NUMA_BUILD && zlc_active && 1615 !zlc_zone_worth_trying(zonelist, z, allowednodes)) 1616 continue; 1617 if ((alloc_flags & ALLOC_CPUSET) && 1618 !cpuset_zone_allowed_softwall(zone, gfp_mask)) 1619 goto try_next_zone; 1620 1621 BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK); 1622 if (!(alloc_flags & ALLOC_NO_WATERMARKS)) { 1623 unsigned long mark; 1624 int ret; 1625 1626 mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK]; 1627 if (zone_watermark_ok(zone, order, mark, 1628 classzone_idx, alloc_flags)) 1629 goto try_this_zone; 1630 1631 if (zone_reclaim_mode == 0) 1632 goto this_zone_full; 1633 1634 ret = zone_reclaim(zone, gfp_mask, order); 1635 switch (ret) { 1636 case ZONE_RECLAIM_NOSCAN: 1637 /* did not scan */ 1638 goto try_next_zone; 1639 case ZONE_RECLAIM_FULL: 1640 /* scanned but unreclaimable */ 1641 goto this_zone_full; 1642 default: 1643 /* did we reclaim enough */ 1644 if (!zone_watermark_ok(zone, order, mark, 1645 classzone_idx, alloc_flags)) 1646 goto this_zone_full; 1647 } 1648 } 1649 1650try_this_zone: 1651 page = buffered_rmqueue(preferred_zone, zone, order, 1652 gfp_mask, migratetype); 1653 if (page) 1654 break; 1655this_zone_full: 1656 if (NUMA_BUILD) 1657 zlc_mark_zone_full(zonelist, z); 1658try_next_zone: 1659 if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) { 1660 /* 1661 * we do zlc_setup after the first zone is tried but only 1662 * if there are multiple nodes make it worthwhile 1663 */ 1664 allowednodes = zlc_setup(zonelist, alloc_flags); 1665 zlc_active = 1; 1666 did_zlc_setup = 1; 1667 } 1668 } 1669 1670 if (unlikely(NUMA_BUILD && page == NULL && zlc_active)) { 1671 /* Disable zlc cache for second zonelist scan */ 1672 zlc_active = 0; 1673 goto zonelist_scan; 1674 } 1675 return page; 1676} 1677 1678static inline int 1679should_alloc_retry(gfp_t gfp_mask, unsigned int order, 1680 unsigned long pages_reclaimed) 1681{ 1682 /* Do not loop if specifically requested */ 1683 if (gfp_mask & __GFP_NORETRY) 1684 return 0; 1685 1686 /* 1687 * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER 1688 * means __GFP_NOFAIL, but that may not be true in other 1689 * implementations. 1690 */ 1691 if (order <= PAGE_ALLOC_COSTLY_ORDER) 1692 return 1; 1693 1694 /* 1695 * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is 1696 * specified, then we retry until we no longer reclaim any pages 1697 * (above), or we've reclaimed an order of pages at least as 1698 * large as the allocation's order. In both cases, if the 1699 * allocation still fails, we stop retrying. 1700 */ 1701 if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order)) 1702 return 1; 1703 1704 /* 1705 * Don't let big-order allocations loop unless the caller 1706 * explicitly requests that. 1707 */ 1708 if (gfp_mask & __GFP_NOFAIL) 1709 return 1; 1710 1711 return 0; 1712} 1713 1714static inline struct page * 1715__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, 1716 struct zonelist *zonelist, enum zone_type high_zoneidx, 1717 nodemask_t *nodemask, struct zone *preferred_zone, 1718 int migratetype) 1719{ 1720 struct page *page; 1721 1722 /* Acquire the OOM killer lock for the zones in zonelist */ 1723 if (!try_set_zone_oom(zonelist, gfp_mask)) { 1724 schedule_timeout_uninterruptible(1); 1725 return NULL; 1726 } 1727 1728 /* 1729 * Go through the zonelist yet one more time, keep very high watermark 1730 * here, this is only to catch a parallel oom killing, we must fail if 1731 * we're still under heavy pressure. 1732 */ 1733 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, 1734 order, zonelist, high_zoneidx, 1735 ALLOC_WMARK_HIGH|ALLOC_CPUSET, 1736 preferred_zone, migratetype); 1737 if (page) 1738 goto out; 1739 1740 if (!(gfp_mask & __GFP_NOFAIL)) { 1741 /* The OOM killer will not help higher order allocs */ 1742 if (order > PAGE_ALLOC_COSTLY_ORDER) 1743 goto out; 1744 /* 1745 * GFP_THISNODE contains __GFP_NORETRY and we never hit this. 1746 * Sanity check for bare calls of __GFP_THISNODE, not real OOM. 1747 * The caller should handle page allocation failure by itself if 1748 * it specifies __GFP_THISNODE. 1749 * Note: Hugepage uses it but will hit PAGE_ALLOC_COSTLY_ORDER. 1750 */ 1751 if (gfp_mask & __GFP_THISNODE) 1752 goto out; 1753 } 1754 /* Exhausted what can be done so it's blamo time */ 1755 out_of_memory(zonelist, gfp_mask, order, nodemask); 1756 1757out: 1758 clear_zonelist_oom(zonelist, gfp_mask); 1759 return page; 1760} 1761 1762#ifdef CONFIG_COMPACTION 1763/* Try memory compaction for high-order allocations before reclaim */ 1764static struct page * 1765__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, 1766 struct zonelist *zonelist, enum zone_type high_zoneidx, 1767 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, 1768 int migratetype, unsigned long *did_some_progress) 1769{ 1770 struct page *page; 1771 1772 if (!order || compaction_deferred(preferred_zone)) 1773 return NULL; 1774 1775 *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask, 1776 nodemask); 1777 if (*did_some_progress != COMPACT_SKIPPED) { 1778 1779 /* Page migration frees to the PCP lists but we want merging */ 1780 drain_pages(get_cpu()); 1781 put_cpu(); 1782 1783 page = get_page_from_freelist(gfp_mask, nodemask, 1784 order, zonelist, high_zoneidx, 1785 alloc_flags, preferred_zone, 1786 migratetype); 1787 if (page) { 1788 preferred_zone->compact_considered = 0; 1789 preferred_zone->compact_defer_shift = 0; 1790 count_vm_event(COMPACTSUCCESS); 1791 return page; 1792 } 1793 1794 /* 1795 * It's bad if compaction run occurs and fails. 1796 * The most likely reason is that pages exist, 1797 * but not enough to satisfy watermarks. 1798 */ 1799 count_vm_event(COMPACTFAIL); 1800 defer_compaction(preferred_zone); 1801 1802 cond_resched(); 1803 } 1804 1805 return NULL; 1806} 1807#else 1808static inline struct page * 1809__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order, 1810 struct zonelist *zonelist, enum zone_type high_zoneidx, 1811 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, 1812 int migratetype, unsigned long *did_some_progress) 1813{ 1814 return NULL; 1815} 1816#endif /* CONFIG_COMPACTION */ 1817 1818/* The really slow allocator path where we enter direct reclaim */ 1819static inline struct page * 1820__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order, 1821 struct zonelist *zonelist, enum zone_type high_zoneidx, 1822 nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone, 1823 int migratetype, unsigned long *did_some_progress) 1824{ 1825 struct page *page = NULL; 1826 struct reclaim_state reclaim_state; 1827 struct task_struct *p = current; 1828 1829 cond_resched(); 1830 1831 /* We now go into synchronous reclaim */ 1832 cpuset_memory_pressure_bump(); 1833 p->flags |= PF_MEMALLOC; 1834 lockdep_set_current_reclaim_state(gfp_mask); 1835 reclaim_state.reclaimed_slab = 0; 1836 p->reclaim_state = &reclaim_state; 1837 1838 *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask); 1839 1840 p->reclaim_state = NULL; 1841 lockdep_clear_current_reclaim_state(); 1842 p->flags &= ~PF_MEMALLOC; 1843 1844 cond_resched(); 1845 1846 if (order != 0) 1847 drain_all_pages(); 1848 1849 if (likely(*did_some_progress)) 1850 page = get_page_from_freelist(gfp_mask, nodemask, order, 1851 zonelist, high_zoneidx, 1852 alloc_flags, preferred_zone, 1853 migratetype); 1854 return page; 1855} 1856 1857/* 1858 * This is called in the allocator slow-path if the allocation request is of 1859 * sufficient urgency to ignore watermarks and take other desperate measures 1860 */ 1861static inline struct page * 1862__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order, 1863 struct zonelist *zonelist, enum zone_type high_zoneidx, 1864 nodemask_t *nodemask, struct zone *preferred_zone, 1865 int migratetype) 1866{ 1867 struct page *page; 1868 1869 do { 1870 page = get_page_from_freelist(gfp_mask, nodemask, order, 1871 zonelist, high_zoneidx, ALLOC_NO_WATERMARKS, 1872 preferred_zone, migratetype); 1873 1874 if (!page && gfp_mask & __GFP_NOFAIL) 1875 congestion_wait(BLK_RW_ASYNC, HZ/50); 1876 } while (!page && (gfp_mask & __GFP_NOFAIL)); 1877 1878 return page; 1879} 1880 1881static inline 1882void wake_all_kswapd(unsigned int order, struct zonelist *zonelist, 1883 enum zone_type high_zoneidx) 1884{ 1885 struct zoneref *z; 1886 struct zone *zone; 1887 1888 for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) 1889 wakeup_kswapd(zone, order); 1890} 1891 1892static inline int 1893gfp_to_alloc_flags(gfp_t gfp_mask) 1894{ 1895 struct task_struct *p = current; 1896 int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET; 1897 const gfp_t wait = gfp_mask & __GFP_WAIT; 1898 1899 /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */ 1900 BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH); 1901 1902 /* 1903 * The caller may dip into page reserves a bit more if the caller 1904 * cannot run direct reclaim, or if the caller has realtime scheduling 1905 * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will 1906 * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH). 1907 */ 1908 alloc_flags |= (gfp_mask & __GFP_HIGH); 1909 1910 if (!wait) { 1911 alloc_flags |= ALLOC_HARDER; 1912 /* 1913 * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc. 1914 * See also cpuset_zone_allowed() comment in kernel/cpuset.c. 1915 */ 1916 alloc_flags &= ~ALLOC_CPUSET; 1917 } else if (unlikely(rt_task(p)) && !in_interrupt()) 1918 alloc_flags |= ALLOC_HARDER; 1919 1920 if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) { 1921 if (!in_interrupt() && 1922 ((p->flags & PF_MEMALLOC) || 1923 unlikely(test_thread_flag(TIF_MEMDIE)))) 1924 alloc_flags |= ALLOC_NO_WATERMARKS; 1925 } 1926 1927 return alloc_flags; 1928} 1929 1930static inline struct page * 1931__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order, 1932 struct zonelist *zonelist, enum zone_type high_zoneidx, 1933 nodemask_t *nodemask, struct zone *preferred_zone, 1934 int migratetype) 1935{ 1936 const gfp_t wait = gfp_mask & __GFP_WAIT; 1937 struct page *page = NULL; 1938 int alloc_flags; 1939 unsigned long pages_reclaimed = 0; 1940 unsigned long did_some_progress; 1941 struct task_struct *p = current; 1942 1943 /* 1944 * In the slowpath, we sanity check order to avoid ever trying to 1945 * reclaim >= MAX_ORDER areas which will never succeed. Callers may 1946 * be using allocators in order of preference for an area that is 1947 * too large. 1948 */ 1949 if (order >= MAX_ORDER) { 1950 WARN_ON_ONCE(!(gfp_mask & __GFP_NOWARN)); 1951 return NULL; 1952 } 1953 1954 /* 1955 * GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and 1956 * __GFP_NOWARN set) should not cause reclaim since the subsystem 1957 * (f.e. slab) using GFP_THISNODE may choose to trigger reclaim 1958 * using a larger set of nodes after it has established that the 1959 * allowed per node queues are empty and that nodes are 1960 * over allocated. 1961 */ 1962 if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE) 1963 goto nopage; 1964 1965restart: 1966 wake_all_kswapd(order, zonelist, high_zoneidx); 1967 1968 /* 1969 * OK, we're below the kswapd watermark and have kicked background 1970 * reclaim. Now things get more complex, so set up alloc_flags according 1971 * to how we want to proceed. 1972 */ 1973 alloc_flags = gfp_to_alloc_flags(gfp_mask); 1974 1975 /* This is the last chance, in general, before the goto nopage. */ 1976 page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist, 1977 high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS, 1978 preferred_zone, migratetype); 1979 if (page) 1980 goto got_pg; 1981 1982rebalance: 1983 /* Allocate without watermarks if the context allows */ 1984 if (alloc_flags & ALLOC_NO_WATERMARKS) { 1985 page = __alloc_pages_high_priority(gfp_mask, order, 1986 zonelist, high_zoneidx, nodemask, 1987 preferred_zone, migratetype); 1988 if (page) 1989 goto got_pg; 1990 } 1991 1992 /* Atomic allocations - we can't balance anything */ 1993 if (!wait) 1994 goto nopage; 1995 1996 /* Avoid recursion of direct reclaim */ 1997 if (p->flags & PF_MEMALLOC) 1998 goto nopage; 1999 2000 /* Avoid allocations with no watermarks from looping endlessly */ 2001 if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL)) 2002 goto nopage; 2003 2004 /* Try direct compaction */ 2005 page = __alloc_pages_direct_compact(gfp_mask, order, 2006 zonelist, high_zoneidx, 2007 nodemask, 2008 alloc_flags, preferred_zone, 2009 migratetype, &did_some_progress); 2010 if (page) 2011 goto got_pg; 2012 2013 /* Try direct reclaim and then allocating */ 2014 page = __alloc_pages_direct_reclaim(gfp_mask, order, 2015 zonelist, high_zoneidx, 2016 nodemask, 2017 alloc_flags, preferred_zone, 2018 migratetype, &did_some_progress); 2019 if (page) 2020 goto got_pg; 2021 2022 /* 2023 * If we failed to make any progress reclaiming, then we are 2024 * running out of options and have to consider going OOM 2025 */ 2026 if (!did_some_progress) { 2027 if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) { 2028 if (oom_killer_disabled) 2029 goto nopage; 2030 page = __alloc_pages_may_oom(gfp_mask, order, 2031 zonelist, high_zoneidx, 2032 nodemask, preferred_zone, 2033 migratetype); 2034 if (page) 2035 goto got_pg; 2036 2037 /* 2038 * The OOM killer does not trigger for high-order 2039 * ~__GFP_NOFAIL allocations so if no progress is being 2040 * made, there are no other options and retrying is 2041 * unlikely to help. 2042 */ 2043 if (order > PAGE_ALLOC_COSTLY_ORDER && 2044 !(gfp_mask & __GFP_NOFAIL)) 2045 goto nopage; 2046 2047 goto restart; 2048 } 2049 } 2050 2051 /* Check if we should retry the allocation */ 2052 pages_reclaimed += did_some_progress; 2053 if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) { 2054 /* Wait for some write requests to complete then retry */ 2055 congestion_wait(BLK_RW_ASYNC, HZ/50); 2056 goto rebalance; 2057 } 2058 2059nopage: 2060 if (!(gfp_mask & __GFP_NOWARN) && printk_ratelimit()) { 2061 printk(KERN_WARNING "%s: page allocation failure." 2062 " order:%d, mode:0x%x\n", 2063 p->comm, order, gfp_mask); 2064 dump_stack(); 2065 show_mem(); 2066 } 2067 return page; 2068got_pg: 2069 if (kmemcheck_enabled) 2070 kmemcheck_pagealloc_alloc(page, order, gfp_mask); 2071 return page; 2072 2073} 2074 2075/* 2076 * This is the 'heart' of the zoned buddy allocator. 2077 */ 2078struct page * 2079__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, 2080 struct zonelist *zonelist, nodemask_t *nodemask) 2081{ 2082 enum zone_type high_zoneidx = gfp_zone(gfp_mask); 2083 struct zone *preferred_zone; 2084 struct page *page; 2085 int migratetype = allocflags_to_migratetype(gfp_mask); 2086 2087 gfp_mask &= gfp_allowed_mask; 2088 2089 lockdep_trace_alloc(gfp_mask); 2090 2091 might_sleep_if(gfp_mask & __GFP_WAIT); 2092 2093 if (should_fail_alloc_page(gfp_mask, order)) 2094 return NULL; 2095 2096 /* 2097 * Check the zones suitable for the gfp_mask contain at least one 2098 * valid zone. It's possible to have an empty zonelist as a result 2099 * of GFP_THISNODE and a memoryless node 2100 */ 2101 if (unlikely(!zonelist->_zonerefs->zone)) 2102 return NULL; 2103 2104 get_mems_allowed(); 2105 /* The preferred zone is used for statistics later */ 2106 first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone); 2107 if (!preferred_zone) { 2108 put_mems_allowed(); 2109 return NULL; 2110 } 2111 2112 /* First allocation attempt */ 2113 page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order, 2114 zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET, 2115 preferred_zone, migratetype); 2116 if (unlikely(!page)) 2117 page = __alloc_pages_slowpath(gfp_mask, order, 2118 zonelist, high_zoneidx, nodemask, 2119 preferred_zone, migratetype); 2120 put_mems_allowed(); 2121 2122 trace_mm_page_alloc(page, order, gfp_mask, migratetype); 2123 return page; 2124} 2125EXPORT_SYMBOL(__alloc_pages_nodemask); 2126 2127/* 2128 * Common helper functions. 2129 */ 2130unsigned long __get_free_pages(gfp_t gfp_mask, unsigned int order) 2131{ 2132 struct page *page; 2133 2134 /* 2135 * __get_free_pages() returns a 32-bit address, which cannot represent 2136 * a highmem page 2137 */ 2138 VM_BUG_ON((gfp_mask & __GFP_HIGHMEM) != 0); 2139 2140 page = alloc_pages(gfp_mask, order); 2141 if (!page) 2142 return 0; 2143 return (unsigned long) page_address(page); 2144} 2145EXPORT_SYMBOL(__get_free_pages); 2146 2147unsigned long get_zeroed_page(gfp_t gfp_mask) 2148{ 2149 return __get_free_pages(gfp_mask | __GFP_ZERO, 0); 2150} 2151EXPORT_SYMBOL(get_zeroed_page); 2152 2153void __pagevec_free(struct pagevec *pvec) 2154{ 2155 int i = pagevec_count(pvec); 2156 2157 while (--i >= 0) { 2158 trace_mm_pagevec_free(pvec->pages[i], pvec->cold); 2159 free_hot_cold_page(pvec->pages[i], pvec->cold); 2160 } 2161} 2162 2163void __free_pages(struct page *page, unsigned int order) 2164{ 2165 if (put_page_testzero(page)) { 2166 if (order == 0) 2167 free_hot_cold_page(page, 0); 2168 else 2169 __free_pages_ok(page, order); 2170 } 2171} 2172 2173EXPORT_SYMBOL(__free_pages); 2174 2175void free_pages(unsigned long addr, unsigned int order) 2176{ 2177 if (addr != 0) { 2178 VM_BUG_ON(!virt_addr_valid((void *)addr)); 2179 __free_pages(virt_to_page((void *)addr), order); 2180 } 2181} 2182 2183EXPORT_SYMBOL(free_pages); 2184 2185/** 2186 * alloc_pages_exact - allocate an exact number physically-contiguous pages. 2187 * @size: the number of bytes to allocate 2188 * @gfp_mask: GFP flags for the allocation 2189 * 2190 * This function is similar to alloc_pages(), except that it allocates the 2191 * minimum number of pages to satisfy the request. alloc_pages() can only 2192 * allocate memory in power-of-two pages. 2193 * 2194 * This function is also limited by MAX_ORDER. 2195 * 2196 * Memory allocated by this function must be released by free_pages_exact(). 2197 */ 2198void *alloc_pages_exact(size_t size, gfp_t gfp_mask) 2199{ 2200 unsigned int order = get_order(size); 2201 unsigned long addr; 2202 2203 addr = __get_free_pages(gfp_mask, order); 2204 if (addr) { 2205 unsigned long alloc_end = addr + (PAGE_SIZE << order); 2206 unsigned long used = addr + PAGE_ALIGN(size); 2207 2208 split_page(virt_to_page((void *)addr), order); 2209 while (used < alloc_end) { 2210 free_page(used); 2211 used += PAGE_SIZE; 2212 } 2213 } 2214 2215 return (void *)addr; 2216} 2217EXPORT_SYMBOL(alloc_pages_exact); 2218 2219/** 2220 * free_pages_exact - release memory allocated via alloc_pages_exact() 2221 * @virt: the value returned by alloc_pages_exact. 2222 * @size: size of allocation, same value as passed to alloc_pages_exact(). 2223 * 2224 * Release the memory allocated by a previous call to alloc_pages_exact. 2225 */ 2226void free_pages_exact(void *virt, size_t size) 2227{ 2228 unsigned long addr = (unsigned long)virt; 2229 unsigned long end = addr + PAGE_ALIGN(size); 2230 2231 while (addr < end) { 2232 free_page(addr); 2233 addr += PAGE_SIZE; 2234 } 2235} 2236EXPORT_SYMBOL(free_pages_exact); 2237 2238static unsigned int nr_free_zone_pages(int offset) 2239{ 2240 struct zoneref *z; 2241 struct zone *zone; 2242 2243 /* Just pick one node, since fallback list is circular */ 2244 unsigned int sum = 0; 2245 2246 struct zonelist *zonelist = node_zonelist(numa_node_id(), GFP_KERNEL); 2247 2248 for_each_zone_zonelist(zone, z, zonelist, offset) { 2249 unsigned long size = zone->present_pages; 2250 unsigned long high = high_wmark_pages(zone); 2251 if (size > high) 2252 sum += size - high; 2253 } 2254 2255 return sum; 2256} 2257 2258/* 2259 * Amount of free RAM allocatable within ZONE_DMA and ZONE_NORMAL 2260 */ 2261unsigned int nr_free_buffer_pages(void) 2262{ 2263 return nr_free_zone_pages(gfp_zone(GFP_USER)); 2264} 2265EXPORT_SYMBOL_GPL(nr_free_buffer_pages); 2266 2267/* 2268 * Amount of free RAM allocatable within all zones 2269 */ 2270unsigned int nr_free_pagecache_pages(void) 2271{ 2272 return nr_free_zone_pages(gfp_zone(GFP_HIGHUSER_MOVABLE)); 2273} 2274 2275static inline void show_node(struct zone *zone) 2276{ 2277 if (NUMA_BUILD) 2278 printk("Node %d ", zone_to_nid(zone)); 2279} 2280 2281void si_meminfo(struct sysinfo *val) 2282{ 2283 val->totalram = totalram_pages; 2284 val->sharedram = 0; 2285 val->freeram = global_page_state(NR_FREE_PAGES); 2286 val->bufferram = nr_blockdev_pages(); 2287 val->totalhigh = totalhigh_pages; 2288 val->freehigh = nr_free_highpages(); 2289 val->mem_unit = PAGE_SIZE; 2290} 2291 2292EXPORT_SYMBOL(si_meminfo); 2293 2294#ifdef CONFIG_NUMA 2295void si_meminfo_node(struct sysinfo *val, int nid) 2296{ 2297 pg_data_t *pgdat = NODE_DATA(nid); 2298 2299 val->totalram = pgdat->node_present_pages; 2300 val->freeram = node_page_state(nid, NR_FREE_PAGES); 2301#ifdef CONFIG_HIGHMEM 2302 val->totalhigh = pgdat->node_zones[ZONE_HIGHMEM].present_pages; 2303 val->freehigh = zone_page_state(&pgdat->node_zones[ZONE_HIGHMEM], 2304 NR_FREE_PAGES); 2305#else 2306 val->totalhigh = 0; 2307 val->freehigh = 0; 2308#endif 2309 val->mem_unit = PAGE_SIZE; 2310} 2311#endif 2312 2313#define K(x) ((x) << (PAGE_SHIFT-10)) 2314 2315/* 2316 * Show free area list (used inside shift_scroll-lock stuff) 2317 * We also calculate the percentage fragmentation. We do this by counting the 2318 * memory on each free list with the exception of the first item on the list. 2319 */ 2320void show_free_areas(void) 2321{ 2322 int cpu; 2323 struct zone *zone; 2324 2325 for_each_populated_zone(zone) { 2326 show_node(zone); 2327 printk("%s per-cpu:\n", zone->name); 2328 2329 for_each_online_cpu(cpu) { 2330 struct per_cpu_pageset *pageset; 2331 2332 pageset = per_cpu_ptr(zone->pageset, cpu); 2333 2334 printk("CPU %4d: hi:%5d, btch:%4d usd:%4d\n", 2335 cpu, pageset->pcp.high, 2336 pageset->pcp.batch, pageset->pcp.count); 2337 } 2338 } 2339 2340 printk("active_anon:%lu inactive_anon:%lu isolated_anon:%lu\n" 2341 " active_file:%lu inactive_file:%lu isolated_file:%lu\n" 2342 " unevictable:%lu" 2343 " dirty:%lu writeback:%lu unstable:%lu\n" 2344 " free:%lu slab_reclaimable:%lu slab_unreclaimable:%lu\n" 2345 " mapped:%lu shmem:%lu pagetables:%lu bounce:%lu\n", 2346 global_page_state(NR_ACTIVE_ANON), 2347 global_page_state(NR_INACTIVE_ANON), 2348 global_page_state(NR_ISOLATED_ANON), 2349 global_page_state(NR_ACTIVE_FILE), 2350 global_page_state(NR_INACTIVE_FILE), 2351 global_page_state(NR_ISOLATED_FILE), 2352 global_page_state(NR_UNEVICTABLE), 2353 global_page_state(NR_FILE_DIRTY), 2354 global_page_state(NR_WRITEBACK), 2355 global_page_state(NR_UNSTABLE_NFS), 2356 global_page_state(NR_FREE_PAGES), 2357 global_page_state(NR_SLAB_RECLAIMABLE), 2358 global_page_state(NR_SLAB_UNRECLAIMABLE), 2359 global_page_state(NR_FILE_MAPPED), 2360 global_page_state(NR_SHMEM), 2361 global_page_state(NR_PAGETABLE), 2362 global_page_state(NR_BOUNCE)); 2363 2364 for_each_populated_zone(zone) { 2365 int i; 2366 2367 show_node(zone); 2368 printk("%s" 2369 " free:%lukB" 2370 " min:%lukB" 2371 " low:%lukB" 2372 " high:%lukB" 2373 " active_anon:%lukB" 2374 " inactive_anon:%lukB" 2375 " active_file:%lukB" 2376 " inactive_file:%lukB" 2377 " unevictable:%lukB" 2378 " isolated(anon):%lukB" 2379 " isolated(file):%lukB" 2380 " present:%lukB" 2381 " mlocked:%lukB" 2382 " dirty:%lukB" 2383 " writeback:%lukB" 2384 " mapped:%lukB" 2385 " shmem:%lukB" 2386 " slab_reclaimable:%lukB" 2387 " slab_unreclaimable:%lukB" 2388 " kernel_stack:%lukB" 2389 " pagetables:%lukB" 2390 " unstable:%lukB" 2391 " bounce:%lukB" 2392 " writeback_tmp:%lukB" 2393 " pages_scanned:%lu" 2394 " all_unreclaimable? %s" 2395 "\n", 2396 zone->name, 2397 K(zone_page_state(zone, NR_FREE_PAGES)), 2398 K(min_wmark_pages(zone)), 2399 K(low_wmark_pages(zone)), 2400 K(high_wmark_pages(zone)), 2401 K(zone_page_state(zone, NR_ACTIVE_ANON)), 2402 K(zone_page_state(zone, NR_INACTIVE_ANON)), 2403 K(zone_page_state(zone, NR_ACTIVE_FILE)), 2404 K(zone_page_state(zone, NR_INACTIVE_FILE)), 2405 K(zone_page_state(zone, NR_UNEVICTABLE)), 2406 K(zone_page_state(zone, NR_ISOLATED_ANON)), 2407 K(zone_page_state(zone, NR_ISOLATED_FILE)), 2408 K(zone->present_pages), 2409 K(zone_page_state(zone, NR_MLOCK)), 2410 K(zone_page_state(zone, NR_FILE_DIRTY)), 2411 K(zone_page_state(zone, NR_WRITEBACK)), 2412 K(zone_page_state(zone, NR_FILE_MAPPED)), 2413 K(zone_page_state(zone, NR_SHMEM)), 2414 K(zone_page_state(zone, NR_SLAB_RECLAIMABLE)), 2415 K(zone_page_state(zone, NR_SLAB_UNRECLAIMABLE)), 2416 zone_page_state(zone, NR_KERNEL_STACK) * 2417 THREAD_SIZE / 1024, 2418 K(zone_page_state(zone, NR_PAGETABLE)), 2419 K(zone_page_state(zone, NR_UNSTABLE_NFS)), 2420 K(zone_page_state(zone, NR_BOUNCE)), 2421 K(zone_page_state(zone, NR_WRITEBACK_TEMP)), 2422 zone->pages_scanned, 2423 (zone->all_unreclaimable ? "yes" : "no") 2424 ); 2425 printk("lowmem_reserve[]:"); 2426 for (i = 0; i < MAX_NR_ZONES; i++) 2427 printk(" %lu", zone->lowmem_reserve[i]); 2428 printk("\n"); 2429 } 2430 2431 for_each_populated_zone(zone) { 2432 unsigned long nr[MAX_ORDER], flags, order, total = 0; 2433 2434 show_node(zone); 2435 printk("%s: ", zone->name); 2436 2437 spin_lock_irqsave(&zone->lock, flags); 2438 for (order = 0; order < MAX_ORDER; order++) { 2439 nr[order] = zone->free_area[order].nr_free; 2440 total += nr[order] << order; 2441 } 2442 spin_unlock_irqrestore(&zone->lock, flags); 2443 for (order = 0; order < MAX_ORDER; order++) 2444 printk("%lu*%lukB ", nr[order], K(1UL) << order); 2445 printk("= %lukB\n", K(total)); 2446 } 2447 2448 printk("%ld total pagecache pages\n", global_page_state(NR_FILE_PAGES)); 2449 2450 show_swap_cache_info(); 2451} 2452 2453static void zoneref_set_zone(struct zone *zone, struct zoneref *zoneref) 2454{ 2455 zoneref->zone = zone; 2456 zoneref->zone_idx = zone_idx(zone); 2457} 2458 2459/* 2460 * Builds allocation fallback zone lists. 2461 * 2462 * Add all populated zones of a node to the zonelist. 2463 */ 2464static int build_zonelists_node(pg_data_t *pgdat, struct zonelist *zonelist, 2465 int nr_zones, enum zone_type zone_type) 2466{ 2467 struct zone *zone; 2468 2469 BUG_ON(zone_type >= MAX_NR_ZONES); 2470 zone_type++; 2471 2472 do { 2473 zone_type--; 2474 zone = pgdat->node_zones + zone_type; 2475 if (populated_zone(zone)) { 2476 zoneref_set_zone(zone, 2477 &zonelist->_zonerefs[nr_zones++]); 2478 check_highest_zone(zone_type); 2479 } 2480 2481 } while (zone_type); 2482 return nr_zones; 2483} 2484 2485 2486/* 2487 * zonelist_order: 2488 * 0 = automatic detection of better ordering. 2489 * 1 = order by ([node] distance, -zonetype) 2490 * 2 = order by (-zonetype, [node] distance) 2491 * 2492 * If not NUMA, ZONELIST_ORDER_ZONE and ZONELIST_ORDER_NODE will create 2493 * the same zonelist. So only NUMA can configure this param. 2494 */ 2495#define ZONELIST_ORDER_DEFAULT 0 2496#define ZONELIST_ORDER_NODE 1 2497#define ZONELIST_ORDER_ZONE 2 2498 2499/* zonelist order in the kernel. 2500 * set_zonelist_order() will set this to NODE or ZONE. 2501 */ 2502static int current_zonelist_order = ZONELIST_ORDER_DEFAULT; 2503static char zonelist_order_name[3][8] = {"Default", "Node", "Zone"}; 2504 2505 2506#ifdef CONFIG_NUMA 2507/* The value user specified ....changed by config */ 2508static int user_zonelist_order = ZONELIST_ORDER_DEFAULT; 2509/* string for sysctl */ 2510#define NUMA_ZONELIST_ORDER_LEN 16 2511char numa_zonelist_order[16] = "default"; 2512 2513/* 2514 * interface for configure zonelist ordering. 2515 * command line option "numa_zonelist_order" 2516 * = "[dD]efault - default, automatic configuration. 2517 * = "[nN]ode - order by node locality, then by zone within node 2518 * = "[zZ]one - order by zone, then by locality within zone 2519 */ 2520 2521static int __parse_numa_zonelist_order(char *s) 2522{ 2523 if (*s == 'd' || *s == 'D') { 2524 user_zonelist_order = ZONELIST_ORDER_DEFAULT; 2525 } else if (*s == 'n' || *s == 'N') { 2526 user_zonelist_order = ZONELIST_ORDER_NODE; 2527 } else if (*s == 'z' || *s == 'Z') { 2528 user_zonelist_order = ZONELIST_ORDER_ZONE; 2529 } else { 2530 printk(KERN_WARNING 2531 "Ignoring invalid numa_zonelist_order value: " 2532 "%s\n", s); 2533 return -EINVAL; 2534 } 2535 return 0; 2536} 2537 2538static __init int setup_numa_zonelist_order(char *s) 2539{ 2540 if (s) 2541 return __parse_numa_zonelist_order(s); 2542 return 0; 2543} 2544early_param("numa_zonelist_order", setup_numa_zonelist_order); 2545 2546/* 2547 * sysctl handler for numa_zonelist_order 2548 */ 2549int numa_zonelist_order_handler(ctl_table *table, int write, 2550 void __user *buffer, size_t *length, 2551 loff_t *ppos) 2552{ 2553 char saved_string[NUMA_ZONELIST_ORDER_LEN]; 2554 int ret; 2555 static DEFINE_MUTEX(zl_order_mutex); 2556 2557 mutex_lock(&zl_order_mutex); 2558 if (write) 2559 strcpy(saved_string, (char*)table->data); 2560 ret = proc_dostring(table, write, buffer, length, ppos); 2561 if (ret) 2562 goto out; 2563 if (write) { 2564 int oldval = user_zonelist_order; 2565 if (__parse_numa_zonelist_order((char*)table->data)) { 2566 /* 2567 * bogus value. restore saved string 2568 */ 2569 strncpy((char*)table->data, saved_string, 2570 NUMA_ZONELIST_ORDER_LEN); 2571 user_zonelist_order = oldval; 2572 } else if (oldval != user_zonelist_order) 2573 build_all_zonelists(); 2574 } 2575out: 2576 mutex_unlock(&zl_order_mutex); 2577 return ret; 2578} 2579 2580 2581#define MAX_NODE_LOAD (nr_online_nodes) 2582static int node_load[MAX_NUMNODES]; 2583 2584/** 2585 * find_next_best_node - find the next node that should appear in a given node's fallback list 2586 * @node: node whose fallback list we're appending 2587 * @used_node_mask: nodemask_t of already used nodes 2588 * 2589 * We use a number of factors to determine which is the next node that should 2590 * appear on a given node's fallback list. The node should not have appeared 2591 * already in @node's fallback list, and it should be the next closest node 2592 * according to the distance array (which contains arbitrary distance values 2593 * from each node to each node in the system), and should also prefer nodes 2594 * with no CPUs, since presumably they'll have very little allocation pressure 2595 * on them otherwise. 2596 * It returns -1 if no node is found. 2597 */ 2598static int find_next_best_node(int node, nodemask_t *used_node_mask) 2599{ 2600 int n, val; 2601 int min_val = INT_MAX; 2602 int best_node = -1; 2603 const struct cpumask *tmp = cpumask_of_node(0); 2604 2605 /* Use the local node if we haven't already */ 2606 if (!node_isset(node, *used_node_mask)) { 2607 node_set(node, *used_node_mask); 2608 return node; 2609 } 2610 2611 for_each_node_state(n, N_HIGH_MEMORY) { 2612 2613 /* Don't want a node to appear more than once */ 2614 if (node_isset(n, *used_node_mask)) 2615 continue; 2616 2617 /* Use the distance array to find the distance */ 2618 val = node_distance(node, n); 2619 2620 /* Penalize nodes under us ("prefer the next node") */ 2621 val += (n < node); 2622 2623 /* Give preference to headless and unused nodes */ 2624 tmp = cpumask_of_node(n); 2625 if (!cpumask_empty(tmp)) 2626 val += PENALTY_FOR_NODE_WITH_CPUS; 2627 2628 /* Slight preference for less loaded node */ 2629 val *= (MAX_NODE_LOAD*MAX_NUMNODES); 2630 val += node_load[n]; 2631 2632 if (val < min_val) { 2633 min_val = val; 2634 best_node = n; 2635 } 2636 } 2637 2638 if (best_node >= 0) 2639 node_set(best_node, *used_node_mask); 2640 2641 return best_node; 2642} 2643 2644 2645/* 2646 * Build zonelists ordered by node and zones within node. 2647 * This results in maximum locality--normal zone overflows into local 2648 * DMA zone, if any--but risks exhausting DMA zone. 2649 */ 2650static void build_zonelists_in_node_order(pg_data_t *pgdat, int node) 2651{ 2652 int j; 2653 struct zonelist *zonelist; 2654 2655 zonelist = &pgdat->node_zonelists[0]; 2656 for (j = 0; zonelist->_zonerefs[j].zone != NULL; j++) 2657 ; 2658 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2659 MAX_NR_ZONES - 1); 2660 zonelist->_zonerefs[j].zone = NULL; 2661 zonelist->_zonerefs[j].zone_idx = 0; 2662} 2663 2664/* 2665 * Build gfp_thisnode zonelists 2666 */ 2667static void build_thisnode_zonelists(pg_data_t *pgdat) 2668{ 2669 int j; 2670 struct zonelist *zonelist; 2671 2672 zonelist = &pgdat->node_zonelists[1]; 2673 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); 2674 zonelist->_zonerefs[j].zone = NULL; 2675 zonelist->_zonerefs[j].zone_idx = 0; 2676} 2677 2678/* 2679 * Build zonelists ordered by zone and nodes within zones. 2680 * This results in conserving DMA zone[s] until all Normal memory is 2681 * exhausted, but results in overflowing to remote node while memory 2682 * may still exist in local DMA zone. 2683 */ 2684static int node_order[MAX_NUMNODES]; 2685 2686static void build_zonelists_in_zone_order(pg_data_t *pgdat, int nr_nodes) 2687{ 2688 int pos, j, node; 2689 int zone_type; /* needs to be signed */ 2690 struct zone *z; 2691 struct zonelist *zonelist; 2692 2693 zonelist = &pgdat->node_zonelists[0]; 2694 pos = 0; 2695 for (zone_type = MAX_NR_ZONES - 1; zone_type >= 0; zone_type--) { 2696 for (j = 0; j < nr_nodes; j++) { 2697 node = node_order[j]; 2698 z = &NODE_DATA(node)->node_zones[zone_type]; 2699 if (populated_zone(z)) { 2700 zoneref_set_zone(z, 2701 &zonelist->_zonerefs[pos++]); 2702 check_highest_zone(zone_type); 2703 } 2704 } 2705 } 2706 zonelist->_zonerefs[pos].zone = NULL; 2707 zonelist->_zonerefs[pos].zone_idx = 0; 2708} 2709 2710static int default_zonelist_order(void) 2711{ 2712 int nid, zone_type; 2713 unsigned long low_kmem_size,total_size; 2714 struct zone *z; 2715 int average_size; 2716 /* 2717 * ZONE_DMA and ZONE_DMA32 can be very small area in the system. 2718 * If they are really small and used heavily, the system can fall 2719 * into OOM very easily. 2720 * This function detect ZONE_DMA/DMA32 size and configures zone order. 2721 */ 2722 /* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */ 2723 low_kmem_size = 0; 2724 total_size = 0; 2725 for_each_online_node(nid) { 2726 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { 2727 z = &NODE_DATA(nid)->node_zones[zone_type]; 2728 if (populated_zone(z)) { 2729 if (zone_type < ZONE_NORMAL) 2730 low_kmem_size += z->present_pages; 2731 total_size += z->present_pages; 2732 } else if (zone_type == ZONE_NORMAL) { 2733 /* 2734 * If any node has only lowmem, then node order 2735 * is preferred to allow kernel allocations 2736 * locally; otherwise, they can easily infringe 2737 * on other nodes when there is an abundance of 2738 * lowmem available to allocate from. 2739 */ 2740 return ZONELIST_ORDER_NODE; 2741 } 2742 } 2743 } 2744 if (!low_kmem_size || /* there are no DMA area. */ 2745 low_kmem_size > total_size/2) /* DMA/DMA32 is big. */ 2746 return ZONELIST_ORDER_NODE; 2747 /* 2748 * look into each node's config. 2749 * If there is a node whose DMA/DMA32 memory is very big area on 2750 * local memory, NODE_ORDER may be suitable. 2751 */ 2752 average_size = total_size / 2753 (nodes_weight(node_states[N_HIGH_MEMORY]) + 1); 2754 for_each_online_node(nid) { 2755 low_kmem_size = 0; 2756 total_size = 0; 2757 for (zone_type = 0; zone_type < MAX_NR_ZONES; zone_type++) { 2758 z = &NODE_DATA(nid)->node_zones[zone_type]; 2759 if (populated_zone(z)) { 2760 if (zone_type < ZONE_NORMAL) 2761 low_kmem_size += z->present_pages; 2762 total_size += z->present_pages; 2763 } 2764 } 2765 if (low_kmem_size && 2766 total_size > average_size && /* ignore small node */ 2767 low_kmem_size > total_size * 70/100) 2768 return ZONELIST_ORDER_NODE; 2769 } 2770 return ZONELIST_ORDER_ZONE; 2771} 2772 2773static void set_zonelist_order(void) 2774{ 2775 if (user_zonelist_order == ZONELIST_ORDER_DEFAULT) 2776 current_zonelist_order = default_zonelist_order(); 2777 else 2778 current_zonelist_order = user_zonelist_order; 2779} 2780 2781static void build_zonelists(pg_data_t *pgdat) 2782{ 2783 int j, node, load; 2784 enum zone_type i; 2785 nodemask_t used_mask; 2786 int local_node, prev_node; 2787 struct zonelist *zonelist; 2788 int order = current_zonelist_order; 2789 2790 /* initialize zonelists */ 2791 for (i = 0; i < MAX_ZONELISTS; i++) { 2792 zonelist = pgdat->node_zonelists + i; 2793 zonelist->_zonerefs[0].zone = NULL; 2794 zonelist->_zonerefs[0].zone_idx = 0; 2795 } 2796 2797 /* NUMA-aware ordering of nodes */ 2798 local_node = pgdat->node_id; 2799 load = nr_online_nodes; 2800 prev_node = local_node; 2801 nodes_clear(used_mask); 2802 2803 memset(node_order, 0, sizeof(node_order)); 2804 j = 0; 2805 2806 while ((node = find_next_best_node(local_node, &used_mask)) >= 0) { 2807 int distance = node_distance(local_node, node); 2808 2809 /* 2810 * If another node is sufficiently far away then it is better 2811 * to reclaim pages in a zone before going off node. 2812 */ 2813 if (distance > RECLAIM_DISTANCE) 2814 zone_reclaim_mode = 1; 2815 2816 /* 2817 * We don't want to pressure a particular node. 2818 * So adding penalty to the first node in same 2819 * distance group to make it round-robin. 2820 */ 2821 if (distance != node_distance(local_node, prev_node)) 2822 node_load[node] = load; 2823 2824 prev_node = node; 2825 load--; 2826 if (order == ZONELIST_ORDER_NODE) 2827 build_zonelists_in_node_order(pgdat, node); 2828 else 2829 node_order[j++] = node; /* remember order */ 2830 } 2831 2832 if (order == ZONELIST_ORDER_ZONE) { 2833 /* calculate node order -- i.e., DMA last! */ 2834 build_zonelists_in_zone_order(pgdat, j); 2835 } 2836 2837 build_thisnode_zonelists(pgdat); 2838} 2839 2840/* Construct the zonelist performance cache - see further mmzone.h */ 2841static void build_zonelist_cache(pg_data_t *pgdat) 2842{ 2843 struct zonelist *zonelist; 2844 struct zonelist_cache *zlc; 2845 struct zoneref *z; 2846 2847 zonelist = &pgdat->node_zonelists[0]; 2848 zonelist->zlcache_ptr = zlc = &zonelist->zlcache; 2849 bitmap_zero(zlc->fullzones, MAX_ZONES_PER_ZONELIST); 2850 for (z = zonelist->_zonerefs; z->zone; z++) 2851 zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z); 2852} 2853 2854 2855#else /* CONFIG_NUMA */ 2856 2857static void set_zonelist_order(void) 2858{ 2859 current_zonelist_order = ZONELIST_ORDER_ZONE; 2860} 2861 2862static void build_zonelists(pg_data_t *pgdat) 2863{ 2864 int node, local_node; 2865 enum zone_type j; 2866 struct zonelist *zonelist; 2867 2868 local_node = pgdat->node_id; 2869 2870 zonelist = &pgdat->node_zonelists[0]; 2871 j = build_zonelists_node(pgdat, zonelist, 0, MAX_NR_ZONES - 1); 2872 2873 /* 2874 * Now we build the zonelist so that it contains the zones 2875 * of all the other nodes. 2876 * We don't want to pressure a particular node, so when 2877 * building the zones for node N, we make sure that the 2878 * zones coming right after the local ones are those from 2879 * node N+1 (modulo N) 2880 */ 2881 for (node = local_node + 1; node < MAX_NUMNODES; node++) { 2882 if (!node_online(node)) 2883 continue; 2884 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2885 MAX_NR_ZONES - 1); 2886 } 2887 for (node = 0; node < local_node; node++) { 2888 if (!node_online(node)) 2889 continue; 2890 j = build_zonelists_node(NODE_DATA(node), zonelist, j, 2891 MAX_NR_ZONES - 1); 2892 } 2893 2894 zonelist->_zonerefs[j].zone = NULL; 2895 zonelist->_zonerefs[j].zone_idx = 0; 2896} 2897 2898/* non-NUMA variant of zonelist performance cache - just NULL zlcache_ptr */ 2899static void build_zonelist_cache(pg_data_t *pgdat) 2900{ 2901 pgdat->node_zonelists[0].zlcache_ptr = NULL; 2902} 2903 2904#endif /* CONFIG_NUMA */ 2905 2906/* 2907 * Boot pageset table. One per cpu which is going to be used for all 2908 * zones and all nodes. The parameters will be set in such a way 2909 * that an item put on a list will immediately be handed over to 2910 * the buddy list. This is safe since pageset manipulation is done 2911 * with interrupts disabled. 2912 * 2913 * The boot_pagesets must be kept even after bootup is complete for 2914 * unused processors and/or zones. They do play a role for bootstrapping 2915 * hotplugged processors. 2916 * 2917 * zoneinfo_show() and maybe other functions do 2918 * not check if the processor is online before following the pageset pointer. 2919 * Other parts of the kernel may not check if the zone is available. 2920 */ 2921static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch); 2922static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset); 2923 2924/* return values int ....just for stop_machine() */ 2925static int __build_all_zonelists(void *dummy) 2926{ 2927 int nid; 2928 int cpu; 2929 2930#ifdef CONFIG_NUMA 2931 memset(node_load, 0, sizeof(node_load)); 2932#endif 2933 for_each_online_node(nid) { 2934 pg_data_t *pgdat = NODE_DATA(nid); 2935 2936 build_zonelists(pgdat); 2937 build_zonelist_cache(pgdat); 2938 } 2939 2940 /* 2941 * Initialize the boot_pagesets that are going to be used 2942 * for bootstrapping processors. The real pagesets for 2943 * each zone will be allocated later when the per cpu 2944 * allocator is available. 2945 * 2946 * boot_pagesets are used also for bootstrapping offline 2947 * cpus if the system is already booted because the pagesets 2948 * are needed to initialize allocators on a specific cpu too. 2949 * F.e. the percpu allocator needs the page allocator which 2950 * needs the percpu allocator in order to allocate its pagesets 2951 * (a chicken-egg dilemma). 2952 */ 2953 for_each_possible_cpu(cpu) 2954 setup_pageset(&per_cpu(boot_pageset, cpu), 0); 2955 2956 return 0; 2957} 2958 2959void build_all_zonelists(void) 2960{ 2961 set_zonelist_order(); 2962 2963 if (system_state == SYSTEM_BOOTING) { 2964 __build_all_zonelists(NULL); 2965 mminit_verify_zonelist(); 2966 cpuset_init_current_mems_allowed(); 2967 } else { 2968 /* we have to stop all cpus to guarantee there is no user 2969 of zonelist */ 2970 stop_machine(__build_all_zonelists, NULL, NULL); 2971 /* cpuset refresh routine should be here */ 2972 } 2973 vm_total_pages = nr_free_pagecache_pages(); 2974 /* 2975 * Disable grouping by mobility if the number of pages in the 2976 * system is too low to allow the mechanism to work. It would be 2977 * more accurate, but expensive to check per-zone. This check is 2978 * made on memory-hotadd so a system can start with mobility 2979 * disabled and enable it later 2980 */ 2981 if (vm_total_pages < (pageblock_nr_pages * MIGRATE_TYPES)) 2982 page_group_by_mobility_disabled = 1; 2983 else 2984 page_group_by_mobility_disabled = 0; 2985 2986 printk("Built %i zonelists in %s order, mobility grouping %s. " 2987 "Total pages: %ld\n", 2988 nr_online_nodes, 2989 zonelist_order_name[current_zonelist_order], 2990 page_group_by_mobility_disabled ? "off" : "on", 2991 vm_total_pages); 2992#ifdef CONFIG_NUMA 2993 printk("Policy zone: %s\n", zone_names[policy_zone]); 2994#endif 2995} 2996 2997/* 2998 * Helper functions to size the waitqueue hash table. 2999 * Essentially these want to choose hash table sizes sufficiently 3000 * large so that collisions trying to wait on pages are rare. 3001 * But in fact, the number of active page waitqueues on typical 3002 * systems is ridiculously low, less than 200. So this is even 3003 * conservative, even though it seems large. 3004 * 3005 * The constant PAGES_PER_WAITQUEUE specifies the ratio of pages to 3006 * waitqueues, i.e. the size of the waitq table given the number of pages. 3007 */ 3008#define PAGES_PER_WAITQUEUE 256 3009 3010#ifndef CONFIG_MEMORY_HOTPLUG 3011static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) 3012{ 3013 unsigned long size = 1; 3014 3015 pages /= PAGES_PER_WAITQUEUE; 3016 3017 while (size < pages) 3018 size <<= 1; 3019 3020 /* 3021 * Once we have dozens or even hundreds of threads sleeping 3022 * on IO we've got bigger problems than wait queue collision. 3023 * Limit the size of the wait table to a reasonable size. 3024 */ 3025 size = min(size, 4096UL); 3026 3027 return max(size, 4UL); 3028} 3029#else 3030/* 3031 * A zone's size might be changed by hot-add, so it is not possible to determine 3032 * a suitable size for its wait_table. So we use the maximum size now. 3033 * 3034 * The max wait table size = 4096 x sizeof(wait_queue_head_t). ie: 3035 * 3036 * i386 (preemption config) : 4096 x 16 = 64Kbyte. 3037 * ia64, x86-64 (no preemption): 4096 x 20 = 80Kbyte. 3038 * ia64, x86-64 (preemption) : 4096 x 24 = 96Kbyte. 3039 * 3040 * The maximum entries are prepared when a zone's memory is (512K + 256) pages 3041 * or more by the traditional way. (See above). It equals: 3042 * 3043 * i386, x86-64, powerpc(4K page size) : = ( 2G + 1M)byte. 3044 * ia64(16K page size) : = ( 8G + 4M)byte. 3045 * powerpc (64K page size) : = (32G +16M)byte. 3046 */ 3047static inline unsigned long wait_table_hash_nr_entries(unsigned long pages) 3048{ 3049 return 4096UL; 3050} 3051#endif 3052 3053/* 3054 * This is an integer logarithm so that shifts can be used later 3055 * to extract the more random high bits from the multiplicative 3056 * hash function before the remainder is taken. 3057 */ 3058static inline unsigned long wait_table_bits(unsigned long size) 3059{ 3060 return ffz(~size); 3061} 3062 3063#define LONG_ALIGN(x) (((x)+(sizeof(long))-1)&~((sizeof(long))-1)) 3064 3065/* 3066 * Mark a number of pageblocks as MIGRATE_RESERVE. The number 3067 * of blocks reserved is based on min_wmark_pages(zone). The memory within 3068 * the reserve will tend to store contiguous free pages. Setting min_free_kbytes 3069 * higher will lead to a bigger reserve which will get freed as contiguous 3070 * blocks as reclaim kicks in 3071 */ 3072static void setup_zone_migrate_reserve(struct zone *zone) 3073{ 3074 unsigned long start_pfn, pfn, end_pfn; 3075 struct page *page; 3076 unsigned long block_migratetype; 3077 int reserve; 3078 3079 /* Get the start pfn, end pfn and the number of blocks to reserve */ 3080 start_pfn = zone->zone_start_pfn; 3081 end_pfn = start_pfn + zone->spanned_pages; 3082 reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >> 3083 pageblock_order; 3084 3085 /* 3086 * Reserve blocks are generally in place to help high-order atomic 3087 * allocations that are short-lived. A min_free_kbytes value that 3088 * would result in more than 2 reserve blocks for atomic allocations 3089 * is assumed to be in place to help anti-fragmentation for the 3090 * future allocation of hugepages at runtime. 3091 */ 3092 reserve = min(2, reserve); 3093 3094 for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) { 3095 if (!pfn_valid(pfn)) 3096 continue; 3097 page = pfn_to_page(pfn); 3098 3099 /* Watch out for overlapping nodes */ 3100 if (page_to_nid(page) != zone_to_nid(zone)) 3101 continue; 3102 3103 /* Blocks with reserved pages will never free, skip them. */ 3104 if (PageReserved(page)) 3105 continue; 3106 3107 block_migratetype = get_pageblock_migratetype(page); 3108 3109 /* If this block is reserved, account for it */ 3110 if (reserve > 0 && block_migratetype == MIGRATE_RESERVE) { 3111 reserve--; 3112 continue; 3113 } 3114 3115 /* Suitable for reserving if this block is movable */ 3116 if (reserve > 0 && block_migratetype == MIGRATE_MOVABLE) { 3117 set_pageblock_migratetype(page, MIGRATE_RESERVE); 3118 move_freepages_block(zone, page, MIGRATE_RESERVE); 3119 reserve--; 3120 continue; 3121 } 3122 3123 /* 3124 * If the reserve is met and this is a previous reserved block, 3125 * take it back 3126 */ 3127 if (block_migratetype == MIGRATE_RESERVE) { 3128 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 3129 move_freepages_block(zone, page, MIGRATE_MOVABLE); 3130 } 3131 } 3132} 3133 3134/* 3135 * Initially all pages are reserved - free ones are freed 3136 * up by free_all_bootmem() once the early boot process is 3137 * done. Non-atomic initialization, single-pass. 3138 */ 3139void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, 3140 unsigned long start_pfn, enum memmap_context context) 3141{ 3142 struct page *page; 3143 unsigned long end_pfn = start_pfn + size; 3144 unsigned long pfn; 3145 struct zone *z; 3146 3147 if (highest_memmap_pfn < end_pfn - 1) 3148 highest_memmap_pfn = end_pfn - 1; 3149 3150 z = &NODE_DATA(nid)->node_zones[zone]; 3151 for (pfn = start_pfn; pfn < end_pfn; pfn++) { 3152 /* 3153 * There can be holes in boot-time mem_map[]s 3154 * handed to this function. They do not 3155 * exist on hotplugged memory. 3156 */ 3157 if (context == MEMMAP_EARLY) { 3158 if (!early_pfn_valid(pfn)) 3159 continue; 3160 if (!early_pfn_in_nid(pfn, nid)) 3161 continue; 3162 } 3163 page = pfn_to_page(pfn); 3164 set_page_links(page, zone, nid, pfn); 3165 mminit_verify_page_links(page, zone, nid, pfn); 3166 init_page_count(page); 3167 reset_page_mapcount(page); 3168 SetPageReserved(page); 3169 /* 3170 * Mark the block movable so that blocks are reserved for 3171 * movable at startup. This will force kernel allocations 3172 * to reserve their blocks rather than leaking throughout 3173 * the address space during boot when many long-lived 3174 * kernel allocations are made. Later some blocks near 3175 * the start are marked MIGRATE_RESERVE by 3176 * setup_zone_migrate_reserve() 3177 * 3178 * bitmap is created for zone's valid pfn range. but memmap 3179 * can be created for invalid pages (for alignment) 3180 * check here not to call set_pageblock_migratetype() against 3181 * pfn out of zone. 3182 */ 3183 if ((z->zone_start_pfn <= pfn) 3184 && (pfn < z->zone_start_pfn + z->spanned_pages) 3185 && !(pfn & (pageblock_nr_pages - 1))) 3186 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 3187 3188 INIT_LIST_HEAD(&page->lru); 3189#ifdef WANT_PAGE_VIRTUAL 3190 /* The shift won't overflow because ZONE_NORMAL is below 4G. */ 3191 if (!is_highmem_idx(zone)) 3192 set_page_address(page, __va(pfn << PAGE_SHIFT)); 3193#endif 3194 } 3195} 3196 3197static void __meminit zone_init_free_lists(struct zone *zone) 3198{ 3199 int order, t; 3200 for_each_migratetype_order(order, t) { 3201 INIT_LIST_HEAD(&zone->free_area[order].free_list[t]); 3202 zone->free_area[order].nr_free = 0; 3203 } 3204} 3205 3206#ifndef __HAVE_ARCH_MEMMAP_INIT 3207#define memmap_init(size, nid, zone, start_pfn) \ 3208 memmap_init_zone((size), (nid), (zone), (start_pfn), MEMMAP_EARLY) 3209#endif 3210 3211static int zone_batchsize(struct zone *zone) 3212{ 3213#ifdef CONFIG_MMU 3214 int batch; 3215 3216 /* 3217 * The per-cpu-pages pools are set to around 1000th of the 3218 * size of the zone. But no more than 1/2 of a meg. 3219 * 3220 * OK, so we don't know how big the cache is. So guess. 3221 */ 3222 batch = zone->present_pages / 1024; 3223 if (batch * PAGE_SIZE > 512 * 1024) 3224 batch = (512 * 1024) / PAGE_SIZE; 3225 batch /= 4; /* We effectively *= 4 below */ 3226 if (batch < 1) 3227 batch = 1; 3228 3229 /* 3230 * Clamp the batch to a 2^n - 1 value. Having a power 3231 * of 2 value was found to be more likely to have 3232 * suboptimal cache aliasing properties in some cases. 3233 * 3234 * For example if 2 tasks are alternately allocating 3235 * batches of pages, one task can end up with a lot 3236 * of pages of one half of the possible page colors 3237 * and the other with pages of the other colors. 3238 */ 3239 batch = rounddown_pow_of_two(batch + batch/2) - 1; 3240 3241 return batch; 3242 3243#else 3244 /* The deferral and batching of frees should be suppressed under NOMMU 3245 * conditions. 3246 * 3247 * The problem is that NOMMU needs to be able to allocate large chunks 3248 * of contiguous memory as there's no hardware page translation to 3249 * assemble apparent contiguous memory from discontiguous pages. 3250 * 3251 * Queueing large contiguous runs of pages for batching, however, 3252 * causes the pages to actually be freed in smaller chunks. As there 3253 * can be a significant delay between the individual batches being 3254 * recycled, this leads to the once large chunks of space being 3255 * fragmented and becoming unavailable for high-order allocations. 3256 */ 3257 return 0; 3258#endif 3259} 3260 3261static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch) 3262{ 3263 struct per_cpu_pages *pcp; 3264 int migratetype; 3265 3266 memset(p, 0, sizeof(*p)); 3267 3268 pcp = &p->pcp; 3269 pcp->count = 0; 3270 pcp->high = 6 * batch; 3271 pcp->batch = max(1UL, 1 * batch); 3272 for (migratetype = 0; migratetype < MIGRATE_PCPTYPES; migratetype++) 3273 INIT_LIST_HEAD(&pcp->lists[migratetype]); 3274} 3275 3276/* 3277 * setup_pagelist_highmark() sets the high water mark for hot per_cpu_pagelist 3278 * to the value high for the pageset p. 3279 */ 3280 3281static void setup_pagelist_highmark(struct per_cpu_pageset *p, 3282 unsigned long high) 3283{ 3284 struct per_cpu_pages *pcp; 3285 3286 pcp = &p->pcp; 3287 pcp->high = high; 3288 pcp->batch = max(1UL, high/4); 3289 if ((high/4) > (PAGE_SHIFT * 8)) 3290 pcp->batch = PAGE_SHIFT * 8; 3291} 3292 3293/* 3294 * Allocate per cpu pagesets and initialize them. 3295 * Before this call only boot pagesets were available. 3296 * Boot pagesets will no longer be used by this processorr 3297 * after setup_per_cpu_pageset(). 3298 */ 3299void __init setup_per_cpu_pageset(void) 3300{ 3301 struct zone *zone; 3302 int cpu; 3303 3304 for_each_populated_zone(zone) { 3305 zone->pageset = alloc_percpu(struct per_cpu_pageset); 3306 3307 for_each_possible_cpu(cpu) { 3308 struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu); 3309 3310 setup_pageset(pcp, zone_batchsize(zone)); 3311 3312 if (percpu_pagelist_fraction) 3313 setup_pagelist_highmark(pcp, 3314 (zone->present_pages / 3315 percpu_pagelist_fraction)); 3316 } 3317 } 3318} 3319 3320static noinline __init_refok 3321int zone_wait_table_init(struct zone *zone, unsigned long zone_size_pages) 3322{ 3323 int i; 3324 struct pglist_data *pgdat = zone->zone_pgdat; 3325 size_t alloc_size; 3326 3327 /* 3328 * The per-page waitqueue mechanism uses hashed waitqueues 3329 * per zone. 3330 */ 3331 zone->wait_table_hash_nr_entries = 3332 wait_table_hash_nr_entries(zone_size_pages); 3333 zone->wait_table_bits = 3334 wait_table_bits(zone->wait_table_hash_nr_entries); 3335 alloc_size = zone->wait_table_hash_nr_entries 3336 * sizeof(wait_queue_head_t); 3337 3338 if (!slab_is_available()) { 3339 zone->wait_table = (wait_queue_head_t *) 3340 alloc_bootmem_node(pgdat, alloc_size); 3341 } else { 3342 /* 3343 * This case means that a zone whose size was 0 gets new memory 3344 * via memory hot-add. 3345 * But it may be the case that a new node was hot-added. In 3346 * this case vmalloc() will not be able to use this new node's 3347 * memory - this wait_table must be initialized to use this new 3348 * node itself as well. 3349 * To use this new node's memory, further consideration will be 3350 * necessary. 3351 */ 3352 zone->wait_table = vmalloc(alloc_size); 3353 } 3354 if (!zone->wait_table) 3355 return -ENOMEM; 3356 3357 for(i = 0; i < zone->wait_table_hash_nr_entries; ++i) 3358 init_waitqueue_head(zone->wait_table + i); 3359 3360 return 0; 3361} 3362 3363static int __zone_pcp_update(void *data) 3364{ 3365 struct zone *zone = data; 3366 int cpu; 3367 unsigned long batch = zone_batchsize(zone), flags; 3368 3369 for_each_possible_cpu(cpu) { 3370 struct per_cpu_pageset *pset; 3371 struct per_cpu_pages *pcp; 3372 3373 pset = per_cpu_ptr(zone->pageset, cpu); 3374 pcp = &pset->pcp; 3375 3376 local_irq_save(flags); 3377 free_pcppages_bulk(zone, pcp->count, pcp); 3378 setup_pageset(pset, batch); 3379 local_irq_restore(flags); 3380 } 3381 return 0; 3382} 3383 3384void zone_pcp_update(struct zone *zone) 3385{ 3386 stop_machine(__zone_pcp_update, zone, NULL); 3387} 3388 3389static __meminit void zone_pcp_init(struct zone *zone) 3390{ 3391 /* 3392 * per cpu subsystem is not up at this point. The following code 3393 * relies on the ability of the linker to provide the 3394 * offset of a (static) per cpu variable into the per cpu area. 3395 */ 3396 zone->pageset = &boot_pageset; 3397 3398 if (zone->present_pages) 3399 printk(KERN_DEBUG " %s zone: %lu pages, LIFO batch:%u\n", 3400 zone->name, zone->present_pages, 3401 zone_batchsize(zone)); 3402} 3403 3404__meminit int init_currently_empty_zone(struct zone *zone, 3405 unsigned long zone_start_pfn, 3406 unsigned long size, 3407 enum memmap_context context) 3408{ 3409 struct pglist_data *pgdat = zone->zone_pgdat; 3410 int ret; 3411 ret = zone_wait_table_init(zone, size); 3412 if (ret) 3413 return ret; 3414 pgdat->nr_zones = zone_idx(zone) + 1; 3415 3416 zone->zone_start_pfn = zone_start_pfn; 3417 3418 mminit_dprintk(MMINIT_TRACE, "memmap_init", 3419 "Initialising map node %d zone %lu pfns %lu -> %lu\n", 3420 pgdat->node_id, 3421 (unsigned long)zone_idx(zone), 3422 zone_start_pfn, (zone_start_pfn + size)); 3423 3424 zone_init_free_lists(zone); 3425 3426 return 0; 3427} 3428 3429#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 3430/* 3431 * Basic iterator support. Return the first range of PFNs for a node 3432 * Note: nid == MAX_NUMNODES returns first region regardless of node 3433 */ 3434static int __meminit first_active_region_index_in_nid(int nid) 3435{ 3436 int i; 3437 3438 for (i = 0; i < nr_nodemap_entries; i++) 3439 if (nid == MAX_NUMNODES || early_node_map[i].nid == nid) 3440 return i; 3441 3442 return -1; 3443} 3444 3445/* 3446 * Basic iterator support. Return the next active range of PFNs for a node 3447 * Note: nid == MAX_NUMNODES returns next region regardless of node 3448 */ 3449static int __meminit next_active_region_index_in_nid(int index, int nid) 3450{ 3451 for (index = index + 1; index < nr_nodemap_entries; index++) 3452 if (nid == MAX_NUMNODES || early_node_map[index].nid == nid) 3453 return index; 3454 3455 return -1; 3456} 3457 3458#ifndef CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID 3459/* 3460 * Required by SPARSEMEM. Given a PFN, return what node the PFN is on. 3461 * Architectures may implement their own version but if add_active_range() 3462 * was used and there are no special requirements, this is a convenient 3463 * alternative 3464 */ 3465int __meminit __early_pfn_to_nid(unsigned long pfn) 3466{ 3467 int i; 3468 3469 for (i = 0; i < nr_nodemap_entries; i++) { 3470 unsigned long start_pfn = early_node_map[i].start_pfn; 3471 unsigned long end_pfn = early_node_map[i].end_pfn; 3472 3473 if (start_pfn <= pfn && pfn < end_pfn) 3474 return early_node_map[i].nid; 3475 } 3476 /* This is a memory hole */ 3477 return -1; 3478} 3479#endif /* CONFIG_HAVE_ARCH_EARLY_PFN_TO_NID */ 3480 3481int __meminit early_pfn_to_nid(unsigned long pfn) 3482{ 3483 int nid; 3484 3485 nid = __early_pfn_to_nid(pfn); 3486 if (nid >= 0) 3487 return nid; 3488 /* just returns 0 */ 3489 return 0; 3490} 3491 3492#ifdef CONFIG_NODES_SPAN_OTHER_NODES 3493bool __meminit early_pfn_in_nid(unsigned long pfn, int node) 3494{ 3495 int nid; 3496 3497 nid = __early_pfn_to_nid(pfn); 3498 if (nid >= 0 && nid != node) 3499 return false; 3500 return true; 3501} 3502#endif 3503 3504/* Basic iterator support to walk early_node_map[] */ 3505#define for_each_active_range_index_in_nid(i, nid) \ 3506 for (i = first_active_region_index_in_nid(nid); i != -1; \ 3507 i = next_active_region_index_in_nid(i, nid)) 3508 3509/** 3510 * free_bootmem_with_active_regions - Call free_bootmem_node for each active range 3511 * @nid: The node to free memory on. If MAX_NUMNODES, all nodes are freed. 3512 * @max_low_pfn: The highest PFN that will be passed to free_bootmem_node 3513 * 3514 * If an architecture guarantees that all ranges registered with 3515 * add_active_ranges() contain no holes and may be freed, this 3516 * this function may be used instead of calling free_bootmem() manually. 3517 */ 3518void __init free_bootmem_with_active_regions(int nid, 3519 unsigned long max_low_pfn) 3520{ 3521 int i; 3522 3523 for_each_active_range_index_in_nid(i, nid) { 3524 unsigned long size_pages = 0; 3525 unsigned long end_pfn = early_node_map[i].end_pfn; 3526 3527 if (early_node_map[i].start_pfn >= max_low_pfn) 3528 continue; 3529 3530 if (end_pfn > max_low_pfn) 3531 end_pfn = max_low_pfn; 3532 3533 size_pages = end_pfn - early_node_map[i].start_pfn; 3534 free_bootmem_node(NODE_DATA(early_node_map[i].nid), 3535 PFN_PHYS(early_node_map[i].start_pfn), 3536 size_pages << PAGE_SHIFT); 3537 } 3538} 3539 3540int __init add_from_early_node_map(struct range *range, int az, 3541 int nr_range, int nid) 3542{ 3543 int i; 3544 u64 start, end; 3545 3546 /* need to go over early_node_map to find out good range for node */ 3547 for_each_active_range_index_in_nid(i, nid) { 3548 start = early_node_map[i].start_pfn; 3549 end = early_node_map[i].end_pfn; 3550 nr_range = add_range(range, az, nr_range, start, end); 3551 } 3552 return nr_range; 3553} 3554 3555#ifdef CONFIG_NO_BOOTMEM 3556void * __init __alloc_memory_core_early(int nid, u64 size, u64 align, 3557 u64 goal, u64 limit) 3558{ 3559 int i; 3560 void *ptr; 3561 3562 /* need to go over early_node_map to find out good range for node */ 3563 for_each_active_range_index_in_nid(i, nid) { 3564 u64 addr; 3565 u64 ei_start, ei_last; 3566 3567 ei_last = early_node_map[i].end_pfn; 3568 ei_last <<= PAGE_SHIFT; 3569 ei_start = early_node_map[i].start_pfn; 3570 ei_start <<= PAGE_SHIFT; 3571 addr = find_early_area(ei_start, ei_last, 3572 goal, limit, size, align); 3573 3574 if (addr == -1ULL) 3575 continue; 3576 3577#if 0 3578 printk(KERN_DEBUG "alloc (nid=%d %llx - %llx) (%llx - %llx) %llx %llx => %llx\n", 3579 nid, 3580 ei_start, ei_last, goal, limit, size, 3581 align, addr); 3582#endif 3583 3584 ptr = phys_to_virt(addr); 3585 memset(ptr, 0, size); 3586 reserve_early_without_check(addr, addr + size, "BOOTMEM"); 3587 return ptr; 3588 } 3589 3590 return NULL; 3591} 3592#endif 3593 3594 3595void __init work_with_active_regions(int nid, work_fn_t work_fn, void *data) 3596{ 3597 int i; 3598 int ret; 3599 3600 for_each_active_range_index_in_nid(i, nid) { 3601 ret = work_fn(early_node_map[i].start_pfn, 3602 early_node_map[i].end_pfn, data); 3603 if (ret) 3604 break; 3605 } 3606} 3607/** 3608 * sparse_memory_present_with_active_regions - Call memory_present for each active range 3609 * @nid: The node to call memory_present for. If MAX_NUMNODES, all nodes will be used. 3610 * 3611 * If an architecture guarantees that all ranges registered with 3612 * add_active_ranges() contain no holes and may be freed, this 3613 * function may be used instead of calling memory_present() manually. 3614 */ 3615void __init sparse_memory_present_with_active_regions(int nid) 3616{ 3617 int i; 3618 3619 for_each_active_range_index_in_nid(i, nid) 3620 memory_present(early_node_map[i].nid, 3621 early_node_map[i].start_pfn, 3622 early_node_map[i].end_pfn); 3623} 3624 3625/** 3626 * get_pfn_range_for_nid - Return the start and end page frames for a node 3627 * @nid: The nid to return the range for. If MAX_NUMNODES, the min and max PFN are returned. 3628 * @start_pfn: Passed by reference. On return, it will have the node start_pfn. 3629 * @end_pfn: Passed by reference. On return, it will have the node end_pfn. 3630 * 3631 * It returns the start and end page frame of a node based on information 3632 * provided by an arch calling add_active_range(). If called for a node 3633 * with no available memory, a warning is printed and the start and end 3634 * PFNs will be 0. 3635 */ 3636void __meminit get_pfn_range_for_nid(unsigned int nid, 3637 unsigned long *start_pfn, unsigned long *end_pfn) 3638{ 3639 int i; 3640 *start_pfn = -1UL; 3641 *end_pfn = 0; 3642 3643 for_each_active_range_index_in_nid(i, nid) { 3644 *start_pfn = min(*start_pfn, early_node_map[i].start_pfn); 3645 *end_pfn = max(*end_pfn, early_node_map[i].end_pfn); 3646 } 3647 3648 if (*start_pfn == -1UL) 3649 *start_pfn = 0; 3650} 3651 3652/* 3653 * This finds a zone that can be used for ZONE_MOVABLE pages. The 3654 * assumption is made that zones within a node are ordered in monotonic 3655 * increasing memory addresses so that the "highest" populated zone is used 3656 */ 3657static void __init find_usable_zone_for_movable(void) 3658{ 3659 int zone_index; 3660 for (zone_index = MAX_NR_ZONES - 1; zone_index >= 0; zone_index--) { 3661 if (zone_index == ZONE_MOVABLE) 3662 continue; 3663 3664 if (arch_zone_highest_possible_pfn[zone_index] > 3665 arch_zone_lowest_possible_pfn[zone_index]) 3666 break; 3667 } 3668 3669 VM_BUG_ON(zone_index == -1); 3670 movable_zone = zone_index; 3671} 3672 3673/* 3674 * The zone ranges provided by the architecture do not include ZONE_MOVABLE 3675 * because it is sized independant of architecture. Unlike the other zones, 3676 * the starting point for ZONE_MOVABLE is not fixed. It may be different 3677 * in each node depending on the size of each node and how evenly kernelcore 3678 * is distributed. This helper function adjusts the zone ranges 3679 * provided by the architecture for a given node by using the end of the 3680 * highest usable zone for ZONE_MOVABLE. This preserves the assumption that 3681 * zones within a node are in order of monotonic increases memory addresses 3682 */ 3683static void __meminit adjust_zone_range_for_zone_movable(int nid, 3684 unsigned long zone_type, 3685 unsigned long node_start_pfn, 3686 unsigned long node_end_pfn, 3687 unsigned long *zone_start_pfn, 3688 unsigned long *zone_end_pfn) 3689{ 3690 /* Only adjust if ZONE_MOVABLE is on this node */ 3691 if (zone_movable_pfn[nid]) { 3692 /* Size ZONE_MOVABLE */ 3693 if (zone_type == ZONE_MOVABLE) { 3694 *zone_start_pfn = zone_movable_pfn[nid]; 3695 *zone_end_pfn = min(node_end_pfn, 3696 arch_zone_highest_possible_pfn[movable_zone]); 3697 3698 /* Adjust for ZONE_MOVABLE starting within this range */ 3699 } else if (*zone_start_pfn < zone_movable_pfn[nid] && 3700 *zone_end_pfn > zone_movable_pfn[nid]) { 3701 *zone_end_pfn = zone_movable_pfn[nid]; 3702 3703 /* Check if this whole range is within ZONE_MOVABLE */ 3704 } else if (*zone_start_pfn >= zone_movable_pfn[nid]) 3705 *zone_start_pfn = *zone_end_pfn; 3706 } 3707} 3708 3709/* 3710 * Return the number of pages a zone spans in a node, including holes 3711 * present_pages = zone_spanned_pages_in_node() - zone_absent_pages_in_node() 3712 */ 3713static unsigned long __meminit zone_spanned_pages_in_node(int nid, 3714 unsigned long zone_type, 3715 unsigned long *ignored) 3716{ 3717 unsigned long node_start_pfn, node_end_pfn; 3718 unsigned long zone_start_pfn, zone_end_pfn; 3719 3720 /* Get the start and end of the node and zone */ 3721 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); 3722 zone_start_pfn = arch_zone_lowest_possible_pfn[zone_type]; 3723 zone_end_pfn = arch_zone_highest_possible_pfn[zone_type]; 3724 adjust_zone_range_for_zone_movable(nid, zone_type, 3725 node_start_pfn, node_end_pfn, 3726 &zone_start_pfn, &zone_end_pfn); 3727 3728 /* Check that this node has pages within the zone's required range */ 3729 if (zone_end_pfn < node_start_pfn || zone_start_pfn > node_end_pfn) 3730 return 0; 3731 3732 /* Move the zone boundaries inside the node if necessary */ 3733 zone_end_pfn = min(zone_end_pfn, node_end_pfn); 3734 zone_start_pfn = max(zone_start_pfn, node_start_pfn); 3735 3736 /* Return the spanned pages */ 3737 return zone_end_pfn - zone_start_pfn; 3738} 3739 3740/* 3741 * Return the number of holes in a range on a node. If nid is MAX_NUMNODES, 3742 * then all holes in the requested range will be accounted for. 3743 */ 3744unsigned long __meminit __absent_pages_in_range(int nid, 3745 unsigned long range_start_pfn, 3746 unsigned long range_end_pfn) 3747{ 3748 int i = 0; 3749 unsigned long prev_end_pfn = 0, hole_pages = 0; 3750 unsigned long start_pfn; 3751 3752 /* Find the end_pfn of the first active range of pfns in the node */ 3753 i = first_active_region_index_in_nid(nid); 3754 if (i == -1) 3755 return 0; 3756 3757 prev_end_pfn = min(early_node_map[i].start_pfn, range_end_pfn); 3758 3759 /* Account for ranges before physical memory on this node */ 3760 if (early_node_map[i].start_pfn > range_start_pfn) 3761 hole_pages = prev_end_pfn - range_start_pfn; 3762 3763 /* Find all holes for the zone within the node */ 3764 for (; i != -1; i = next_active_region_index_in_nid(i, nid)) { 3765 3766 /* No need to continue if prev_end_pfn is outside the zone */ 3767 if (prev_end_pfn >= range_end_pfn) 3768 break; 3769 3770 /* Make sure the end of the zone is not within the hole */ 3771 start_pfn = min(early_node_map[i].start_pfn, range_end_pfn); 3772 prev_end_pfn = max(prev_end_pfn, range_start_pfn); 3773 3774 /* Update the hole size cound and move on */ 3775 if (start_pfn > range_start_pfn) { 3776 BUG_ON(prev_end_pfn > start_pfn); 3777 hole_pages += start_pfn - prev_end_pfn; 3778 } 3779 prev_end_pfn = early_node_map[i].end_pfn; 3780 } 3781 3782 /* Account for ranges past physical memory on this node */ 3783 if (range_end_pfn > prev_end_pfn) 3784 hole_pages += range_end_pfn - 3785 max(range_start_pfn, prev_end_pfn); 3786 3787 return hole_pages; 3788} 3789 3790/** 3791 * absent_pages_in_range - Return number of page frames in holes within a range 3792 * @start_pfn: The start PFN to start searching for holes 3793 * @end_pfn: The end PFN to stop searching for holes 3794 * 3795 * It returns the number of pages frames in memory holes within a range. 3796 */ 3797unsigned long __init absent_pages_in_range(unsigned long start_pfn, 3798 unsigned long end_pfn) 3799{ 3800 return __absent_pages_in_range(MAX_NUMNODES, start_pfn, end_pfn); 3801} 3802 3803/* Return the number of page frames in holes in a zone on a node */ 3804static unsigned long __meminit zone_absent_pages_in_node(int nid, 3805 unsigned long zone_type, 3806 unsigned long *ignored) 3807{ 3808 unsigned long node_start_pfn, node_end_pfn; 3809 unsigned long zone_start_pfn, zone_end_pfn; 3810 3811 get_pfn_range_for_nid(nid, &node_start_pfn, &node_end_pfn); 3812 zone_start_pfn = max(arch_zone_lowest_possible_pfn[zone_type], 3813 node_start_pfn); 3814 zone_end_pfn = min(arch_zone_highest_possible_pfn[zone_type], 3815 node_end_pfn); 3816 3817 adjust_zone_range_for_zone_movable(nid, zone_type, 3818 node_start_pfn, node_end_pfn, 3819 &zone_start_pfn, &zone_end_pfn); 3820 return __absent_pages_in_range(nid, zone_start_pfn, zone_end_pfn); 3821} 3822 3823#else 3824static inline unsigned long __meminit zone_spanned_pages_in_node(int nid, 3825 unsigned long zone_type, 3826 unsigned long *zones_size) 3827{ 3828 return zones_size[zone_type]; 3829} 3830 3831static inline unsigned long __meminit zone_absent_pages_in_node(int nid, 3832 unsigned long zone_type, 3833 unsigned long *zholes_size) 3834{ 3835 if (!zholes_size) 3836 return 0; 3837 3838 return zholes_size[zone_type]; 3839} 3840 3841#endif 3842 3843static void __meminit calculate_node_totalpages(struct pglist_data *pgdat, 3844 unsigned long *zones_size, unsigned long *zholes_size) 3845{ 3846 unsigned long realtotalpages, totalpages = 0; 3847 enum zone_type i; 3848 3849 for (i = 0; i < MAX_NR_ZONES; i++) 3850 totalpages += zone_spanned_pages_in_node(pgdat->node_id, i, 3851 zones_size); 3852 pgdat->node_spanned_pages = totalpages; 3853 3854 realtotalpages = totalpages; 3855 for (i = 0; i < MAX_NR_ZONES; i++) 3856 realtotalpages -= 3857 zone_absent_pages_in_node(pgdat->node_id, i, 3858 zholes_size); 3859 pgdat->node_present_pages = realtotalpages; 3860 printk(KERN_DEBUG "On node %d totalpages: %lu\n", pgdat->node_id, 3861 realtotalpages); 3862} 3863 3864#ifndef CONFIG_SPARSEMEM 3865/* 3866 * Calculate the size of the zone->blockflags rounded to an unsigned long 3867 * Start by making sure zonesize is a multiple of pageblock_order by rounding 3868 * up. Then use 1 NR_PAGEBLOCK_BITS worth of bits per pageblock, finally 3869 * round what is now in bits to nearest long in bits, then return it in 3870 * bytes. 3871 */ 3872static unsigned long __init usemap_size(unsigned long zonesize) 3873{ 3874 unsigned long usemapsize; 3875 3876 usemapsize = roundup(zonesize, pageblock_nr_pages); 3877 usemapsize = usemapsize >> pageblock_order; 3878 usemapsize *= NR_PAGEBLOCK_BITS; 3879 usemapsize = roundup(usemapsize, 8 * sizeof(unsigned long)); 3880 3881 return usemapsize / 8; 3882} 3883 3884static void __init setup_usemap(struct pglist_data *pgdat, 3885 struct zone *zone, unsigned long zonesize) 3886{ 3887 unsigned long usemapsize = usemap_size(zonesize); 3888 zone->pageblock_flags = NULL; 3889 if (usemapsize) 3890 zone->pageblock_flags = alloc_bootmem_node(pgdat, usemapsize); 3891} 3892#else 3893static void inline setup_usemap(struct pglist_data *pgdat, 3894 struct zone *zone, unsigned long zonesize) {} 3895#endif /* CONFIG_SPARSEMEM */ 3896 3897#ifdef CONFIG_HUGETLB_PAGE_SIZE_VARIABLE 3898 3899/* Return a sensible default order for the pageblock size. */ 3900static inline int pageblock_default_order(void) 3901{ 3902 if (HPAGE_SHIFT > PAGE_SHIFT) 3903 return HUGETLB_PAGE_ORDER; 3904 3905 return MAX_ORDER-1; 3906} 3907 3908/* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ 3909static inline void __init set_pageblock_order(unsigned int order) 3910{ 3911 /* Check that pageblock_nr_pages has not already been setup */ 3912 if (pageblock_order) 3913 return; 3914 3915 /* 3916 * Assume the largest contiguous order of interest is a huge page. 3917 * This value may be variable depending on boot parameters on IA64 3918 */ 3919 pageblock_order = order; 3920} 3921#else /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ 3922 3923/* 3924 * When CONFIG_HUGETLB_PAGE_SIZE_VARIABLE is not set, set_pageblock_order() 3925 * and pageblock_default_order() are unused as pageblock_order is set 3926 * at compile-time. See include/linux/pageblock-flags.h for the values of 3927 * pageblock_order based on the kernel config 3928 */ 3929static inline int pageblock_default_order(unsigned int order) 3930{ 3931 return MAX_ORDER-1; 3932} 3933#define set_pageblock_order(x) do {} while (0) 3934 3935#endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ 3936 3937/* 3938 * Set up the zone data structures: 3939 * - mark all pages reserved 3940 * - mark all memory queues empty 3941 * - clear the memory bitmaps 3942 */ 3943static void __paginginit free_area_init_core(struct pglist_data *pgdat, 3944 unsigned long *zones_size, unsigned long *zholes_size) 3945{ 3946 enum zone_type j; 3947 int nid = pgdat->node_id; 3948 unsigned long zone_start_pfn = pgdat->node_start_pfn; 3949 int ret; 3950 3951 pgdat_resize_init(pgdat); 3952 pgdat->nr_zones = 0; 3953 init_waitqueue_head(&pgdat->kswapd_wait); 3954 pgdat->kswapd_max_order = 0; 3955 pgdat_page_cgroup_init(pgdat); 3956 3957 for (j = 0; j < MAX_NR_ZONES; j++) { 3958 struct zone *zone = pgdat->node_zones + j; 3959 unsigned long size, realsize, memmap_pages; 3960 enum lru_list l; 3961 3962 size = zone_spanned_pages_in_node(nid, j, zones_size); 3963 realsize = size - zone_absent_pages_in_node(nid, j, 3964 zholes_size); 3965 3966 /* 3967 * Adjust realsize so that it accounts for how much memory 3968 * is used by this zone for memmap. This affects the watermark 3969 * and per-cpu initialisations 3970 */ 3971 memmap_pages = 3972 PAGE_ALIGN(size * sizeof(struct page)) >> PAGE_SHIFT; 3973 if (realsize >= memmap_pages) { 3974 realsize -= memmap_pages; 3975 if (memmap_pages) 3976 printk(KERN_DEBUG 3977 " %s zone: %lu pages used for memmap\n", 3978 zone_names[j], memmap_pages); 3979 } else 3980 printk(KERN_WARNING 3981 " %s zone: %lu pages exceeds realsize %lu\n", 3982 zone_names[j], memmap_pages, realsize); 3983 3984 /* Account for reserved pages */ 3985 if (j == 0 && realsize > dma_reserve) { 3986 realsize -= dma_reserve; 3987 printk(KERN_DEBUG " %s zone: %lu pages reserved\n", 3988 zone_names[0], dma_reserve); 3989 } 3990 3991 if (!is_highmem_idx(j)) 3992 nr_kernel_pages += realsize; 3993 nr_all_pages += realsize; 3994 3995 zone->spanned_pages = size; 3996 zone->present_pages = realsize; 3997#ifdef CONFIG_NUMA 3998 zone->node = nid; 3999 zone->min_unmapped_pages = (realsize*sysctl_min_unmapped_ratio) 4000 / 100; 4001 zone->min_slab_pages = (realsize * sysctl_min_slab_ratio) / 100; 4002#endif 4003 zone->name = zone_names[j]; 4004 spin_lock_init(&zone->lock); 4005 spin_lock_init(&zone->lru_lock); 4006 zone_seqlock_init(zone); 4007 zone->zone_pgdat = pgdat; 4008 4009 zone->prev_priority = DEF_PRIORITY; 4010 4011 zone_pcp_init(zone); 4012 for_each_lru(l) { 4013 INIT_LIST_HEAD(&zone->lru[l].list); 4014 zone->reclaim_stat.nr_saved_scan[l] = 0; 4015 } 4016 zone->reclaim_stat.recent_rotated[0] = 0; 4017 zone->reclaim_stat.recent_rotated[1] = 0; 4018 zone->reclaim_stat.recent_scanned[0] = 0; 4019 zone->reclaim_stat.recent_scanned[1] = 0; 4020 zap_zone_vm_stats(zone); 4021 zone->flags = 0; 4022 if (!size) 4023 continue; 4024 4025 set_pageblock_order(pageblock_default_order()); 4026 setup_usemap(pgdat, zone, size); 4027 ret = init_currently_empty_zone(zone, zone_start_pfn, 4028 size, MEMMAP_EARLY); 4029 BUG_ON(ret); 4030 memmap_init(size, nid, j, zone_start_pfn); 4031 zone_start_pfn += size; 4032 } 4033} 4034 4035static void __init_refok alloc_node_mem_map(struct pglist_data *pgdat) 4036{ 4037 /* Skip empty nodes */ 4038 if (!pgdat->node_spanned_pages) 4039 return; 4040 4041#ifdef CONFIG_FLAT_NODE_MEM_MAP 4042 /* ia64 gets its own node_mem_map, before this, without bootmem */ 4043 if (!pgdat->node_mem_map) { 4044 unsigned long size, start, end; 4045 struct page *map; 4046 4047 /* 4048 * The zone's endpoints aren't required to be MAX_ORDER 4049 * aligned but the node_mem_map endpoints must be in order 4050 * for the buddy allocator to function correctly. 4051 */ 4052 start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1); 4053 end = pgdat->node_start_pfn + pgdat->node_spanned_pages; 4054 end = ALIGN(end, MAX_ORDER_NR_PAGES); 4055 size = (end - start) * sizeof(struct page); 4056 map = alloc_remap(pgdat->node_id, size); 4057 if (!map) 4058 map = alloc_bootmem_node(pgdat, size); 4059 pgdat->node_mem_map = map + (pgdat->node_start_pfn - start); 4060 } 4061#ifndef CONFIG_NEED_MULTIPLE_NODES 4062 /* 4063 * With no DISCONTIG, the global mem_map is just set as node 0's 4064 */ 4065 if (pgdat == NODE_DATA(0)) { 4066 mem_map = NODE_DATA(0)->node_mem_map; 4067#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 4068 if (page_to_pfn(mem_map) != pgdat->node_start_pfn) 4069 mem_map -= (pgdat->node_start_pfn - ARCH_PFN_OFFSET); 4070#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 4071 } 4072#endif 4073#endif /* CONFIG_FLAT_NODE_MEM_MAP */ 4074} 4075 4076void __paginginit free_area_init_node(int nid, unsigned long *zones_size, 4077 unsigned long node_start_pfn, unsigned long *zholes_size) 4078{ 4079 pg_data_t *pgdat = NODE_DATA(nid); 4080 4081 pgdat->node_id = nid; 4082 pgdat->node_start_pfn = node_start_pfn; 4083 calculate_node_totalpages(pgdat, zones_size, zholes_size); 4084 4085 alloc_node_mem_map(pgdat); 4086#ifdef CONFIG_FLAT_NODE_MEM_MAP 4087 printk(KERN_DEBUG "free_area_init_node: node %d, pgdat %08lx, node_mem_map %08lx\n", 4088 nid, (unsigned long)pgdat, 4089 (unsigned long)pgdat->node_mem_map); 4090#endif 4091 4092 free_area_init_core(pgdat, zones_size, zholes_size); 4093} 4094 4095#ifdef CONFIG_ARCH_POPULATES_NODE_MAP 4096 4097#if MAX_NUMNODES > 1 4098/* 4099 * Figure out the number of possible node ids. 4100 */ 4101static void __init setup_nr_node_ids(void) 4102{ 4103 unsigned int node; 4104 unsigned int highest = 0; 4105 4106 for_each_node_mask(node, node_possible_map) 4107 highest = node; 4108 nr_node_ids = highest + 1; 4109} 4110#else 4111static inline void setup_nr_node_ids(void) 4112{ 4113} 4114#endif 4115 4116/** 4117 * add_active_range - Register a range of PFNs backed by physical memory 4118 * @nid: The node ID the range resides on 4119 * @start_pfn: The start PFN of the available physical memory 4120 * @end_pfn: The end PFN of the available physical memory 4121 * 4122 * These ranges are stored in an early_node_map[] and later used by 4123 * free_area_init_nodes() to calculate zone sizes and holes. If the 4124 * range spans a memory hole, it is up to the architecture to ensure 4125 * the memory is not freed by the bootmem allocator. If possible 4126 * the range being registered will be merged with existing ranges. 4127 */ 4128void __init add_active_range(unsigned int nid, unsigned long start_pfn, 4129 unsigned long end_pfn) 4130{ 4131 int i; 4132 4133 mminit_dprintk(MMINIT_TRACE, "memory_register", 4134 "Entering add_active_range(%d, %#lx, %#lx) " 4135 "%d entries of %d used\n", 4136 nid, start_pfn, end_pfn, 4137 nr_nodemap_entries, MAX_ACTIVE_REGIONS); 4138 4139 mminit_validate_memmodel_limits(&start_pfn, &end_pfn); 4140 4141 /* Merge with existing active regions if possible */ 4142 for (i = 0; i < nr_nodemap_entries; i++) { 4143 if (early_node_map[i].nid != nid) 4144 continue; 4145 4146 /* Skip if an existing region covers this new one */ 4147 if (start_pfn >= early_node_map[i].start_pfn && 4148 end_pfn <= early_node_map[i].end_pfn) 4149 return; 4150 4151 /* Merge forward if suitable */ 4152 if (start_pfn <= early_node_map[i].end_pfn && 4153 end_pfn > early_node_map[i].end_pfn) { 4154 early_node_map[i].end_pfn = end_pfn; 4155 return; 4156 } 4157 4158 /* Merge backward if suitable */ 4159 if (start_pfn < early_node_map[i].start_pfn && 4160 end_pfn >= early_node_map[i].start_pfn) { 4161 early_node_map[i].start_pfn = start_pfn; 4162 return; 4163 } 4164 } 4165 4166 /* Check that early_node_map is large enough */ 4167 if (i >= MAX_ACTIVE_REGIONS) { 4168 printk(KERN_CRIT "More than %d memory regions, truncating\n", 4169 MAX_ACTIVE_REGIONS); 4170 return; 4171 } 4172 4173 early_node_map[i].nid = nid; 4174 early_node_map[i].start_pfn = start_pfn; 4175 early_node_map[i].end_pfn = end_pfn; 4176 nr_nodemap_entries = i + 1; 4177} 4178 4179/** 4180 * remove_active_range - Shrink an existing registered range of PFNs 4181 * @nid: The node id the range is on that should be shrunk 4182 * @start_pfn: The new PFN of the range 4183 * @end_pfn: The new PFN of the range 4184 * 4185 * i386 with NUMA use alloc_remap() to store a node_mem_map on a local node. 4186 * The map is kept near the end physical page range that has already been 4187 * registered. This function allows an arch to shrink an existing registered 4188 * range. 4189 */ 4190void __init remove_active_range(unsigned int nid, unsigned long start_pfn, 4191 unsigned long end_pfn) 4192{ 4193 int i, j; 4194 int removed = 0; 4195 4196 printk(KERN_DEBUG "remove_active_range (%d, %lu, %lu)\n", 4197 nid, start_pfn, end_pfn); 4198 4199 /* Find the old active region end and shrink */ 4200 for_each_active_range_index_in_nid(i, nid) { 4201 if (early_node_map[i].start_pfn >= start_pfn && 4202 early_node_map[i].end_pfn <= end_pfn) { 4203 /* clear it */ 4204 early_node_map[i].start_pfn = 0; 4205 early_node_map[i].end_pfn = 0; 4206 removed = 1; 4207 continue; 4208 } 4209 if (early_node_map[i].start_pfn < start_pfn && 4210 early_node_map[i].end_pfn > start_pfn) { 4211 unsigned long temp_end_pfn = early_node_map[i].end_pfn; 4212 early_node_map[i].end_pfn = start_pfn; 4213 if (temp_end_pfn > end_pfn) 4214 add_active_range(nid, end_pfn, temp_end_pfn); 4215 continue; 4216 } 4217 if (early_node_map[i].start_pfn >= start_pfn && 4218 early_node_map[i].end_pfn > end_pfn && 4219 early_node_map[i].start_pfn < end_pfn) { 4220 early_node_map[i].start_pfn = end_pfn; 4221 continue; 4222 } 4223 } 4224 4225 if (!removed) 4226 return; 4227 4228 /* remove the blank ones */ 4229 for (i = nr_nodemap_entries - 1; i > 0; i--) { 4230 if (early_node_map[i].nid != nid) 4231 continue; 4232 if (early_node_map[i].end_pfn) 4233 continue; 4234 /* we found it, get rid of it */ 4235 for (j = i; j < nr_nodemap_entries - 1; j++) 4236 memcpy(&early_node_map[j], &early_node_map[j+1], 4237 sizeof(early_node_map[j])); 4238 j = nr_nodemap_entries - 1; 4239 memset(&early_node_map[j], 0, sizeof(early_node_map[j])); 4240 nr_nodemap_entries--; 4241 } 4242} 4243 4244/** 4245 * remove_all_active_ranges - Remove all currently registered regions 4246 * 4247 * During discovery, it may be found that a table like SRAT is invalid 4248 * and an alternative discovery method must be used. This function removes 4249 * all currently registered regions. 4250 */ 4251void __init remove_all_active_ranges(void) 4252{ 4253 memset(early_node_map, 0, sizeof(early_node_map)); 4254 nr_nodemap_entries = 0; 4255} 4256 4257/* Compare two active node_active_regions */ 4258static int __init cmp_node_active_region(const void *a, const void *b) 4259{ 4260 struct node_active_region *arange = (struct node_active_region *)a; 4261 struct node_active_region *brange = (struct node_active_region *)b; 4262 4263 /* Done this way to avoid overflows */ 4264 if (arange->start_pfn > brange->start_pfn) 4265 return 1; 4266 if (arange->start_pfn < brange->start_pfn) 4267 return -1; 4268 4269 return 0; 4270} 4271 4272/* sort the node_map by start_pfn */ 4273void __init sort_node_map(void) 4274{ 4275 sort(early_node_map, (size_t)nr_nodemap_entries, 4276 sizeof(struct node_active_region), 4277 cmp_node_active_region, NULL); 4278} 4279 4280/* Find the lowest pfn for a node */ 4281static unsigned long __init find_min_pfn_for_node(int nid) 4282{ 4283 int i; 4284 unsigned long min_pfn = ULONG_MAX; 4285 4286 /* Assuming a sorted map, the first range found has the starting pfn */ 4287 for_each_active_range_index_in_nid(i, nid) 4288 min_pfn = min(min_pfn, early_node_map[i].start_pfn); 4289 4290 if (min_pfn == ULONG_MAX) { 4291 printk(KERN_WARNING 4292 "Could not find start_pfn for node %d\n", nid); 4293 return 0; 4294 } 4295 4296 return min_pfn; 4297} 4298 4299/** 4300 * find_min_pfn_with_active_regions - Find the minimum PFN registered 4301 * 4302 * It returns the minimum PFN based on information provided via 4303 * add_active_range(). 4304 */ 4305unsigned long __init find_min_pfn_with_active_regions(void) 4306{ 4307 return find_min_pfn_for_node(MAX_NUMNODES); 4308} 4309 4310/* 4311 * early_calculate_totalpages() 4312 * Sum pages in active regions for movable zone. 4313 * Populate N_HIGH_MEMORY for calculating usable_nodes. 4314 */ 4315static unsigned long __init early_calculate_totalpages(void) 4316{ 4317 int i; 4318 unsigned long totalpages = 0; 4319 4320 for (i = 0; i < nr_nodemap_entries; i++) { 4321 unsigned long pages = early_node_map[i].end_pfn - 4322 early_node_map[i].start_pfn; 4323 totalpages += pages; 4324 if (pages) 4325 node_set_state(early_node_map[i].nid, N_HIGH_MEMORY); 4326 } 4327 return totalpages; 4328} 4329 4330/* 4331 * Find the PFN the Movable zone begins in each node. Kernel memory 4332 * is spread evenly between nodes as long as the nodes have enough 4333 * memory. When they don't, some nodes will have more kernelcore than 4334 * others 4335 */ 4336static void __init find_zone_movable_pfns_for_nodes(unsigned long *movable_pfn) 4337{ 4338 int i, nid; 4339 unsigned long usable_startpfn; 4340 unsigned long kernelcore_node, kernelcore_remaining; 4341 /* save the state before borrow the nodemask */ 4342 nodemask_t saved_node_state = node_states[N_HIGH_MEMORY]; 4343 unsigned long totalpages = early_calculate_totalpages(); 4344 int usable_nodes = nodes_weight(node_states[N_HIGH_MEMORY]); 4345 4346 /* 4347 * If movablecore was specified, calculate what size of 4348 * kernelcore that corresponds so that memory usable for 4349 * any allocation type is evenly spread. If both kernelcore 4350 * and movablecore are specified, then the value of kernelcore 4351 * will be used for required_kernelcore if it's greater than 4352 * what movablecore would have allowed. 4353 */ 4354 if (required_movablecore) { 4355 unsigned long corepages; 4356 4357 /* 4358 * Round-up so that ZONE_MOVABLE is at least as large as what 4359 * was requested by the user 4360 */ 4361 required_movablecore = 4362 roundup(required_movablecore, MAX_ORDER_NR_PAGES); 4363 corepages = totalpages - required_movablecore; 4364 4365 required_kernelcore = max(required_kernelcore, corepages); 4366 } 4367 4368 /* If kernelcore was not specified, there is no ZONE_MOVABLE */ 4369 if (!required_kernelcore) 4370 goto out; 4371 4372 /* usable_startpfn is the lowest possible pfn ZONE_MOVABLE can be at */ 4373 find_usable_zone_for_movable(); 4374 usable_startpfn = arch_zone_lowest_possible_pfn[movable_zone]; 4375 4376restart: 4377 /* Spread kernelcore memory as evenly as possible throughout nodes */ 4378 kernelcore_node = required_kernelcore / usable_nodes; 4379 for_each_node_state(nid, N_HIGH_MEMORY) { 4380 /* 4381 * Recalculate kernelcore_node if the division per node 4382 * now exceeds what is necessary to satisfy the requested 4383 * amount of memory for the kernel 4384 */ 4385 if (required_kernelcore < kernelcore_node) 4386 kernelcore_node = required_kernelcore / usable_nodes; 4387 4388 /* 4389 * As the map is walked, we track how much memory is usable 4390 * by the kernel using kernelcore_remaining. When it is 4391 * 0, the rest of the node is usable by ZONE_MOVABLE 4392 */ 4393 kernelcore_remaining = kernelcore_node; 4394 4395 /* Go through each range of PFNs within this node */ 4396 for_each_active_range_index_in_nid(i, nid) { 4397 unsigned long start_pfn, end_pfn; 4398 unsigned long size_pages; 4399 4400 start_pfn = max(early_node_map[i].start_pfn, 4401 zone_movable_pfn[nid]); 4402 end_pfn = early_node_map[i].end_pfn; 4403 if (start_pfn >= end_pfn) 4404 continue; 4405 4406 /* Account for what is only usable for kernelcore */ 4407 if (start_pfn < usable_startpfn) { 4408 unsigned long kernel_pages; 4409 kernel_pages = min(end_pfn, usable_startpfn) 4410 - start_pfn; 4411 4412 kernelcore_remaining -= min(kernel_pages, 4413 kernelcore_remaining); 4414 required_kernelcore -= min(kernel_pages, 4415 required_kernelcore); 4416 4417 /* Continue if range is now fully accounted */ 4418 if (end_pfn <= usable_startpfn) { 4419 4420 /* 4421 * Push zone_movable_pfn to the end so 4422 * that if we have to rebalance 4423 * kernelcore across nodes, we will 4424 * not double account here 4425 */ 4426 zone_movable_pfn[nid] = end_pfn; 4427 continue; 4428 } 4429 start_pfn = usable_startpfn; 4430 } 4431 4432 /* 4433 * The usable PFN range for ZONE_MOVABLE is from 4434 * start_pfn->end_pfn. Calculate size_pages as the 4435 * number of pages used as kernelcore 4436 */ 4437 size_pages = end_pfn - start_pfn; 4438 if (size_pages > kernelcore_remaining) 4439 size_pages = kernelcore_remaining; 4440 zone_movable_pfn[nid] = start_pfn + size_pages; 4441 4442 /* 4443 * Some kernelcore has been met, update counts and 4444 * break if the kernelcore for this node has been 4445 * satisified 4446 */ 4447 required_kernelcore -= min(required_kernelcore, 4448 size_pages); 4449 kernelcore_remaining -= size_pages; 4450 if (!kernelcore_remaining) 4451 break; 4452 } 4453 } 4454 4455 /* 4456 * If there is still required_kernelcore, we do another pass with one 4457 * less node in the count. This will push zone_movable_pfn[nid] further 4458 * along on the nodes that still have memory until kernelcore is 4459 * satisified 4460 */ 4461 usable_nodes--; 4462 if (usable_nodes && required_kernelcore > usable_nodes) 4463 goto restart; 4464 4465 /* Align start of ZONE_MOVABLE on all nids to MAX_ORDER_NR_PAGES */ 4466 for (nid = 0; nid < MAX_NUMNODES; nid++) 4467 zone_movable_pfn[nid] = 4468 roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES); 4469 4470out: 4471 /* restore the node_state */ 4472 node_states[N_HIGH_MEMORY] = saved_node_state; 4473} 4474 4475/* Any regular memory on that node ? */ 4476static void check_for_regular_memory(pg_data_t *pgdat) 4477{ 4478#ifdef CONFIG_HIGHMEM 4479 enum zone_type zone_type; 4480 4481 for (zone_type = 0; zone_type <= ZONE_NORMAL; zone_type++) { 4482 struct zone *zone = &pgdat->node_zones[zone_type]; 4483 if (zone->present_pages) 4484 node_set_state(zone_to_nid(zone), N_NORMAL_MEMORY); 4485 } 4486#endif 4487} 4488 4489/** 4490 * free_area_init_nodes - Initialise all pg_data_t and zone data 4491 * @max_zone_pfn: an array of max PFNs for each zone 4492 * 4493 * This will call free_area_init_node() for each active node in the system. 4494 * Using the page ranges provided by add_active_range(), the size of each 4495 * zone in each node and their holes is calculated. If the maximum PFN 4496 * between two adjacent zones match, it is assumed that the zone is empty. 4497 * For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed 4498 * that arch_max_dma32_pfn has no pages. It is also assumed that a zone 4499 * starts where the previous one ended. For example, ZONE_DMA32 starts 4500 * at arch_max_dma_pfn. 4501 */ 4502void __init free_area_init_nodes(unsigned long *max_zone_pfn) 4503{ 4504 unsigned long nid; 4505 int i; 4506 4507 /* Sort early_node_map as initialisation assumes it is sorted */ 4508 sort_node_map(); 4509 4510 /* Record where the zone boundaries are */ 4511 memset(arch_zone_lowest_possible_pfn, 0, 4512 sizeof(arch_zone_lowest_possible_pfn)); 4513 memset(arch_zone_highest_possible_pfn, 0, 4514 sizeof(arch_zone_highest_possible_pfn)); 4515 arch_zone_lowest_possible_pfn[0] = find_min_pfn_with_active_regions(); 4516 arch_zone_highest_possible_pfn[0] = max_zone_pfn[0]; 4517 for (i = 1; i < MAX_NR_ZONES; i++) { 4518 if (i == ZONE_MOVABLE) 4519 continue; 4520 arch_zone_lowest_possible_pfn[i] = 4521 arch_zone_highest_possible_pfn[i-1]; 4522 arch_zone_highest_possible_pfn[i] = 4523 max(max_zone_pfn[i], arch_zone_lowest_possible_pfn[i]); 4524 } 4525 arch_zone_lowest_possible_pfn[ZONE_MOVABLE] = 0; 4526 arch_zone_highest_possible_pfn[ZONE_MOVABLE] = 0; 4527 4528 /* Find the PFNs that ZONE_MOVABLE begins at in each node */ 4529 memset(zone_movable_pfn, 0, sizeof(zone_movable_pfn)); 4530 find_zone_movable_pfns_for_nodes(zone_movable_pfn); 4531 4532 /* Print out the zone ranges */ 4533 printk("Zone PFN ranges:\n"); 4534 for (i = 0; i < MAX_NR_ZONES; i++) { 4535 if (i == ZONE_MOVABLE) 4536 continue; 4537 printk(" %-8s ", zone_names[i]); 4538 if (arch_zone_lowest_possible_pfn[i] == 4539 arch_zone_highest_possible_pfn[i]) 4540 printk("empty\n"); 4541 else 4542 printk("%0#10lx -> %0#10lx\n", 4543 arch_zone_lowest_possible_pfn[i], 4544 arch_zone_highest_possible_pfn[i]); 4545 } 4546 4547 /* Print out the PFNs ZONE_MOVABLE begins at in each node */ 4548 printk("Movable zone start PFN for each node\n"); 4549 for (i = 0; i < MAX_NUMNODES; i++) { 4550 if (zone_movable_pfn[i]) 4551 printk(" Node %d: %lu\n", i, zone_movable_pfn[i]); 4552 } 4553 4554 /* Print out the early_node_map[] */ 4555 printk("early_node_map[%d] active PFN ranges\n", nr_nodemap_entries); 4556 for (i = 0; i < nr_nodemap_entries; i++) 4557 printk(" %3d: %0#10lx -> %0#10lx\n", early_node_map[i].nid, 4558 early_node_map[i].start_pfn, 4559 early_node_map[i].end_pfn); 4560 4561 /* Initialise every node */ 4562 mminit_verify_pageflags_layout(); 4563 setup_nr_node_ids(); 4564 for_each_online_node(nid) { 4565 pg_data_t *pgdat = NODE_DATA(nid); 4566 free_area_init_node(nid, NULL, 4567 find_min_pfn_for_node(nid), NULL); 4568 4569 /* Any memory on that node */ 4570 if (pgdat->node_present_pages) 4571 node_set_state(nid, N_HIGH_MEMORY); 4572 check_for_regular_memory(pgdat); 4573 } 4574} 4575 4576static int __init cmdline_parse_core(char *p, unsigned long *core) 4577{ 4578 unsigned long long coremem; 4579 if (!p) 4580 return -EINVAL; 4581 4582 coremem = memparse(p, &p); 4583 *core = coremem >> PAGE_SHIFT; 4584 4585 /* Paranoid check that UL is enough for the coremem value */ 4586 WARN_ON((coremem >> PAGE_SHIFT) > ULONG_MAX); 4587 4588 return 0; 4589} 4590 4591/* 4592 * kernelcore=size sets the amount of memory for use for allocations that 4593 * cannot be reclaimed or migrated. 4594 */ 4595static int __init cmdline_parse_kernelcore(char *p) 4596{ 4597 return cmdline_parse_core(p, &required_kernelcore); 4598} 4599 4600/* 4601 * movablecore=size sets the amount of memory for use for allocations that 4602 * can be reclaimed or migrated. 4603 */ 4604static int __init cmdline_parse_movablecore(char *p) 4605{ 4606 return cmdline_parse_core(p, &required_movablecore); 4607} 4608 4609early_param("kernelcore", cmdline_parse_kernelcore); 4610early_param("movablecore", cmdline_parse_movablecore); 4611 4612#endif /* CONFIG_ARCH_POPULATES_NODE_MAP */ 4613 4614/** 4615 * set_dma_reserve - set the specified number of pages reserved in the first zone 4616 * @new_dma_reserve: The number of pages to mark reserved 4617 * 4618 * The per-cpu batchsize and zone watermarks are determined by present_pages. 4619 * In the DMA zone, a significant percentage may be consumed by kernel image 4620 * and other unfreeable allocations which can skew the watermarks badly. This 4621 * function may optionally be used to account for unfreeable pages in the 4622 * first zone (e.g., ZONE_DMA). The effect will be lower watermarks and 4623 * smaller per-cpu batchsize. 4624 */ 4625void __init set_dma_reserve(unsigned long new_dma_reserve) 4626{ 4627 dma_reserve = new_dma_reserve; 4628} 4629 4630#ifndef CONFIG_NEED_MULTIPLE_NODES 4631struct pglist_data __refdata contig_page_data = { 4632#ifndef CONFIG_NO_BOOTMEM 4633 .bdata = &bootmem_node_data[0] 4634#endif 4635 }; 4636EXPORT_SYMBOL(contig_page_data); 4637#endif 4638 4639void __init free_area_init(unsigned long *zones_size) 4640{ 4641 free_area_init_node(0, zones_size, 4642 __pa(PAGE_OFFSET) >> PAGE_SHIFT, NULL); 4643} 4644 4645static int page_alloc_cpu_notify(struct notifier_block *self, 4646 unsigned long action, void *hcpu) 4647{ 4648 int cpu = (unsigned long)hcpu; 4649 4650 if (action == CPU_DEAD || action == CPU_DEAD_FROZEN) { 4651 drain_pages(cpu); 4652 4653 /* 4654 * Spill the event counters of the dead processor 4655 * into the current processors event counters. 4656 * This artificially elevates the count of the current 4657 * processor. 4658 */ 4659 vm_events_fold_cpu(cpu); 4660 4661 /* 4662 * Zero the differential counters of the dead processor 4663 * so that the vm statistics are consistent. 4664 * 4665 * This is only okay since the processor is dead and cannot 4666 * race with what we are doing. 4667 */ 4668 refresh_cpu_vm_stats(cpu); 4669 } 4670 return NOTIFY_OK; 4671} 4672 4673void __init page_alloc_init(void) 4674{ 4675 hotcpu_notifier(page_alloc_cpu_notify, 0); 4676} 4677 4678/* 4679 * calculate_totalreserve_pages - called when sysctl_lower_zone_reserve_ratio 4680 * or min_free_kbytes changes. 4681 */ 4682static void calculate_totalreserve_pages(void) 4683{ 4684 struct pglist_data *pgdat; 4685 unsigned long reserve_pages = 0; 4686 enum zone_type i, j; 4687 4688 for_each_online_pgdat(pgdat) { 4689 for (i = 0; i < MAX_NR_ZONES; i++) { 4690 struct zone *zone = pgdat->node_zones + i; 4691 unsigned long max = 0; 4692 4693 /* Find valid and maximum lowmem_reserve in the zone */ 4694 for (j = i; j < MAX_NR_ZONES; j++) { 4695 if (zone->lowmem_reserve[j] > max) 4696 max = zone->lowmem_reserve[j]; 4697 } 4698 4699 /* we treat the high watermark as reserved pages. */ 4700 max += high_wmark_pages(zone); 4701 4702 if (max > zone->present_pages) 4703 max = zone->present_pages; 4704 reserve_pages += max; 4705 } 4706 } 4707 totalreserve_pages = reserve_pages; 4708} 4709 4710/* 4711 * setup_per_zone_lowmem_reserve - called whenever 4712 * sysctl_lower_zone_reserve_ratio changes. Ensures that each zone 4713 * has a correct pages reserved value, so an adequate number of 4714 * pages are left in the zone after a successful __alloc_pages(). 4715 */ 4716static void setup_per_zone_lowmem_reserve(void) 4717{ 4718 struct pglist_data *pgdat; 4719 enum zone_type j, idx; 4720 4721 for_each_online_pgdat(pgdat) { 4722 for (j = 0; j < MAX_NR_ZONES; j++) { 4723 struct zone *zone = pgdat->node_zones + j; 4724 unsigned long present_pages = zone->present_pages; 4725 4726 zone->lowmem_reserve[j] = 0; 4727 4728 idx = j; 4729 while (idx) { 4730 struct zone *lower_zone; 4731 4732 idx--; 4733 4734 if (sysctl_lowmem_reserve_ratio[idx] < 1) 4735 sysctl_lowmem_reserve_ratio[idx] = 1; 4736 4737 lower_zone = pgdat->node_zones + idx; 4738 lower_zone->lowmem_reserve[j] = present_pages / 4739 sysctl_lowmem_reserve_ratio[idx]; 4740 present_pages += lower_zone->present_pages; 4741 } 4742 } 4743 } 4744 4745 /* update totalreserve_pages */ 4746 calculate_totalreserve_pages(); 4747} 4748 4749/** 4750 * setup_per_zone_wmarks - called when min_free_kbytes changes 4751 * or when memory is hot-{added|removed} 4752 * 4753 * Ensures that the watermark[min,low,high] values for each zone are set 4754 * correctly with respect to min_free_kbytes. 4755 */ 4756void setup_per_zone_wmarks(void) 4757{ 4758 unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10); 4759 unsigned long lowmem_pages = 0; 4760 struct zone *zone; 4761 unsigned long flags; 4762 4763 /* Calculate total number of !ZONE_HIGHMEM pages */ 4764 for_each_zone(zone) { 4765 if (!is_highmem(zone)) 4766 lowmem_pages += zone->present_pages; 4767 } 4768 4769 for_each_zone(zone) { 4770 u64 tmp; 4771 4772 spin_lock_irqsave(&zone->lock, flags); 4773 tmp = (u64)pages_min * zone->present_pages; 4774 do_div(tmp, lowmem_pages); 4775 if (is_highmem(zone)) { 4776 /* 4777 * __GFP_HIGH and PF_MEMALLOC allocations usually don't 4778 * need highmem pages, so cap pages_min to a small 4779 * value here. 4780 * 4781 * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN) 4782 * deltas controls asynch page reclaim, and so should 4783 * not be capped for highmem. 4784 */ 4785 int min_pages; 4786 4787 min_pages = zone->present_pages / 1024; 4788 if (min_pages < SWAP_CLUSTER_MAX) 4789 min_pages = SWAP_CLUSTER_MAX; 4790 if (min_pages > 128) 4791 min_pages = 128; 4792 zone->watermark[WMARK_MIN] = min_pages; 4793 } else { 4794 /* 4795 * If it's a lowmem zone, reserve a number of pages 4796 * proportionate to the zone's size. 4797 */ 4798 zone->watermark[WMARK_MIN] = tmp; 4799 } 4800 4801 zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2); 4802 zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1); 4803 setup_zone_migrate_reserve(zone); 4804 spin_unlock_irqrestore(&zone->lock, flags); 4805 } 4806 4807 /* update totalreserve_pages */ 4808 calculate_totalreserve_pages(); 4809} 4810 4811/* 4812 * The inactive anon list should be small enough that the VM never has to 4813 * do too much work, but large enough that each inactive page has a chance 4814 * to be referenced again before it is swapped out. 4815 * 4816 * The inactive_anon ratio is the target ratio of ACTIVE_ANON to 4817 * INACTIVE_ANON pages on this zone's LRU, maintained by the 4818 * pageout code. A zone->inactive_ratio of 3 means 3:1 or 25% of 4819 * the anonymous pages are kept on the inactive list. 4820 * 4821 * total target max 4822 * memory ratio inactive anon 4823 * ------------------------------------- 4824 * 10MB 1 5MB 4825 * 100MB 1 50MB 4826 * 1GB 3 250MB 4827 * 10GB 10 0.9GB 4828 * 100GB 31 3GB 4829 * 1TB 101 10GB 4830 * 10TB 320 32GB 4831 */ 4832void calculate_zone_inactive_ratio(struct zone *zone) 4833{ 4834 unsigned int gb, ratio; 4835 4836 /* Zone size in gigabytes */ 4837 gb = zone->present_pages >> (30 - PAGE_SHIFT); 4838 if (gb) 4839 ratio = int_sqrt(10 * gb); 4840 else 4841 ratio = 1; 4842 4843 zone->inactive_ratio = ratio; 4844} 4845 4846static void __init setup_per_zone_inactive_ratio(void) 4847{ 4848 struct zone *zone; 4849 4850 for_each_zone(zone) 4851 calculate_zone_inactive_ratio(zone); 4852} 4853 4854/* 4855 * Initialise min_free_kbytes. 4856 * 4857 * For small machines we want it small (128k min). For large machines 4858 * we want it large (64MB max). But it is not linear, because network 4859 * bandwidth does not increase linearly with machine size. We use 4860 * 4861 * min_free_kbytes = 4 * sqrt(lowmem_kbytes), for better accuracy: 4862 * min_free_kbytes = sqrt(lowmem_kbytes * 16) 4863 * 4864 * which yields 4865 * 4866 * 16MB: 512k 4867 * 32MB: 724k 4868 * 64MB: 1024k 4869 * 128MB: 1448k 4870 * 256MB: 2048k 4871 * 512MB: 2896k 4872 * 1024MB: 4096k 4873 * 2048MB: 5792k 4874 * 4096MB: 8192k 4875 * 8192MB: 11584k 4876 * 16384MB: 16384k 4877 */ 4878static int __init init_per_zone_wmark_min(void) 4879{ 4880 unsigned long lowmem_kbytes; 4881 4882 lowmem_kbytes = nr_free_buffer_pages() * (PAGE_SIZE >> 10); 4883 4884 min_free_kbytes = int_sqrt(lowmem_kbytes * 16); 4885 if (min_free_kbytes < 128) 4886 min_free_kbytes = 128; 4887 if (min_free_kbytes > 65536) 4888 min_free_kbytes = 65536; 4889 setup_per_zone_wmarks(); 4890 setup_per_zone_lowmem_reserve(); 4891 setup_per_zone_inactive_ratio(); 4892 return 0; 4893} 4894module_init(init_per_zone_wmark_min) 4895 4896/* 4897 * min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so 4898 * that we can call two helper functions whenever min_free_kbytes 4899 * changes. 4900 */ 4901int min_free_kbytes_sysctl_handler(ctl_table *table, int write, 4902 void __user *buffer, size_t *length, loff_t *ppos) 4903{ 4904 proc_dointvec(table, write, buffer, length, ppos); 4905 if (write) 4906 setup_per_zone_wmarks(); 4907 return 0; 4908} 4909 4910#ifdef CONFIG_NUMA 4911int sysctl_min_unmapped_ratio_sysctl_handler(ctl_table *table, int write, 4912 void __user *buffer, size_t *length, loff_t *ppos) 4913{ 4914 struct zone *zone; 4915 int rc; 4916 4917 rc = proc_dointvec_minmax(table, write, buffer, length, ppos); 4918 if (rc) 4919 return rc; 4920 4921 for_each_zone(zone) 4922 zone->min_unmapped_pages = (zone->present_pages * 4923 sysctl_min_unmapped_ratio) / 100; 4924 return 0; 4925} 4926 4927int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write, 4928 void __user *buffer, size_t *length, loff_t *ppos) 4929{ 4930 struct zone *zone; 4931 int rc; 4932 4933 rc = proc_dointvec_minmax(table, write, buffer, length, ppos); 4934 if (rc) 4935 return rc; 4936 4937 for_each_zone(zone) 4938 zone->min_slab_pages = (zone->present_pages * 4939 sysctl_min_slab_ratio) / 100; 4940 return 0; 4941} 4942#endif 4943 4944/* 4945 * lowmem_reserve_ratio_sysctl_handler - just a wrapper around 4946 * proc_dointvec() so that we can call setup_per_zone_lowmem_reserve() 4947 * whenever sysctl_lowmem_reserve_ratio changes. 4948 * 4949 * The reserve ratio obviously has absolutely no relation with the 4950 * minimum watermarks. The lowmem reserve ratio can only make sense 4951 * if in function of the boot time zone sizes. 4952 */ 4953int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write, 4954 void __user *buffer, size_t *length, loff_t *ppos) 4955{ 4956 proc_dointvec_minmax(table, write, buffer, length, ppos); 4957 setup_per_zone_lowmem_reserve(); 4958 return 0; 4959} 4960 4961/* 4962 * percpu_pagelist_fraction - changes the pcp->high for each zone on each 4963 * cpu. It is the fraction of total pages in each zone that a hot per cpu pagelist 4964 * can have before it gets flushed back to buddy allocator. 4965 */ 4966 4967int percpu_pagelist_fraction_sysctl_handler(ctl_table *table, int write, 4968 void __user *buffer, size_t *length, loff_t *ppos) 4969{ 4970 struct zone *zone; 4971 unsigned int cpu; 4972 int ret; 4973 4974 ret = proc_dointvec_minmax(table, write, buffer, length, ppos); 4975 if (!write || (ret == -EINVAL)) 4976 return ret; 4977 for_each_populated_zone(zone) { 4978 for_each_possible_cpu(cpu) { 4979 unsigned long high; 4980 high = zone->present_pages / percpu_pagelist_fraction; 4981 setup_pagelist_highmark( 4982 per_cpu_ptr(zone->pageset, cpu), high); 4983 } 4984 } 4985 return 0; 4986} 4987 4988int hashdist = HASHDIST_DEFAULT; 4989 4990#ifdef CONFIG_NUMA 4991static int __init set_hashdist(char *str) 4992{ 4993 if (!str) 4994 return 0; 4995 hashdist = simple_strtoul(str, &str, 0); 4996 return 1; 4997} 4998__setup("hashdist=", set_hashdist); 4999#endif 5000 5001/* 5002 * allocate a large system hash table from bootmem 5003 * - it is assumed that the hash table must contain an exact power-of-2 5004 * quantity of entries 5005 * - limit is the number of hash buckets, not the total allocation size 5006 */ 5007void *__init alloc_large_system_hash(const char *tablename, 5008 unsigned long bucketsize, 5009 unsigned long numentries, 5010 int scale, 5011 int flags, 5012 unsigned int *_hash_shift, 5013 unsigned int *_hash_mask, 5014 unsigned long limit) 5015{ 5016 unsigned long long max = limit; 5017 unsigned long log2qty, size; 5018 void *table = NULL; 5019 5020 /* allow the kernel cmdline to have a say */ 5021 if (!numentries) { 5022 /* round applicable memory size up to nearest megabyte */ 5023 numentries = nr_kernel_pages; 5024 numentries += (1UL << (20 - PAGE_SHIFT)) - 1; 5025 numentries >>= 20 - PAGE_SHIFT; 5026 numentries <<= 20 - PAGE_SHIFT; 5027 5028 /* limit to 1 bucket per 2^scale bytes of low memory */ 5029 if (scale > PAGE_SHIFT) 5030 numentries >>= (scale - PAGE_SHIFT); 5031 else 5032 numentries <<= (PAGE_SHIFT - scale); 5033 5034 /* Make sure we've got at least a 0-order allocation.. */ 5035 if (unlikely(flags & HASH_SMALL)) { 5036 /* Makes no sense without HASH_EARLY */ 5037 WARN_ON(!(flags & HASH_EARLY)); 5038 if (!(numentries >> *_hash_shift)) { 5039 numentries = 1UL << *_hash_shift; 5040 BUG_ON(!numentries); 5041 } 5042 } else if (unlikely((numentries * bucketsize) < PAGE_SIZE)) 5043 numentries = PAGE_SIZE / bucketsize; 5044 } 5045 numentries = roundup_pow_of_two(numentries); 5046 5047 /* limit allocation size to 1/16 total memory by default */ 5048 if (max == 0) { 5049 max = ((unsigned long long)nr_all_pages << PAGE_SHIFT) >> 4; 5050 do_div(max, bucketsize); 5051 } 5052 5053 if (numentries > max) 5054 numentries = max; 5055 5056 log2qty = ilog2(numentries); 5057 5058 do { 5059 size = bucketsize << log2qty; 5060 if (flags & HASH_EARLY) 5061 table = alloc_bootmem_nopanic(size); 5062 else if (hashdist) 5063 table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL); 5064 else { 5065 /* 5066 * If bucketsize is not a power-of-two, we may free 5067 * some pages at the end of hash table which 5068 * alloc_pages_exact() automatically does 5069 */ 5070 if (get_order(size) < MAX_ORDER) { 5071 table = alloc_pages_exact(size, GFP_ATOMIC); 5072 kmemleak_alloc(table, size, 1, GFP_ATOMIC); 5073 } 5074 } 5075 } while (!table && size > PAGE_SIZE && --log2qty); 5076 5077 if (!table) 5078 panic("Failed to allocate %s hash table\n", tablename); 5079 5080 printk(KERN_INFO "%s hash table entries: %d (order: %d, %lu bytes)\n", 5081 tablename, 5082 (1U << log2qty), 5083 ilog2(size) - PAGE_SHIFT, 5084 size); 5085 5086 if (_hash_shift) 5087 *_hash_shift = log2qty; 5088 if (_hash_mask) 5089 *_hash_mask = (1 << log2qty) - 1; 5090 5091 return table; 5092} 5093 5094/* Return a pointer to the bitmap storing bits affecting a block of pages */ 5095static inline unsigned long *get_pageblock_bitmap(struct zone *zone, 5096 unsigned long pfn) 5097{ 5098#ifdef CONFIG_SPARSEMEM 5099 return __pfn_to_section(pfn)->pageblock_flags; 5100#else 5101 return zone->pageblock_flags; 5102#endif /* CONFIG_SPARSEMEM */ 5103} 5104 5105static inline int pfn_to_bitidx(struct zone *zone, unsigned long pfn) 5106{ 5107#ifdef CONFIG_SPARSEMEM 5108 pfn &= (PAGES_PER_SECTION-1); 5109 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; 5110#else 5111 pfn = pfn - zone->zone_start_pfn; 5112 return (pfn >> pageblock_order) * NR_PAGEBLOCK_BITS; 5113#endif /* CONFIG_SPARSEMEM */ 5114} 5115 5116/** 5117 * get_pageblock_flags_group - Return the requested group of flags for the pageblock_nr_pages block of pages 5118 * @page: The page within the block of interest 5119 * @start_bitidx: The first bit of interest to retrieve 5120 * @end_bitidx: The last bit of interest 5121 * returns pageblock_bits flags 5122 */ 5123unsigned long get_pageblock_flags_group(struct page *page, 5124 int start_bitidx, int end_bitidx) 5125{ 5126 struct zone *zone; 5127 unsigned long *bitmap; 5128 unsigned long pfn, bitidx; 5129 unsigned long flags = 0; 5130 unsigned long value = 1; 5131 5132 zone = page_zone(page); 5133 pfn = page_to_pfn(page); 5134 bitmap = get_pageblock_bitmap(zone, pfn); 5135 bitidx = pfn_to_bitidx(zone, pfn); 5136 5137 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) 5138 if (test_bit(bitidx + start_bitidx, bitmap)) 5139 flags |= value; 5140 5141 return flags; 5142} 5143 5144/** 5145 * set_pageblock_flags_group - Set the requested group of flags for a pageblock_nr_pages block of pages 5146 * @page: The page within the block of interest 5147 * @start_bitidx: The first bit of interest 5148 * @end_bitidx: The last bit of interest 5149 * @flags: The flags to set 5150 */ 5151void set_pageblock_flags_group(struct page *page, unsigned long flags, 5152 int start_bitidx, int end_bitidx) 5153{ 5154 struct zone *zone; 5155 unsigned long *bitmap; 5156 unsigned long pfn, bitidx; 5157 unsigned long value = 1; 5158 5159 zone = page_zone(page); 5160 pfn = page_to_pfn(page); 5161 bitmap = get_pageblock_bitmap(zone, pfn); 5162 bitidx = pfn_to_bitidx(zone, pfn); 5163 VM_BUG_ON(pfn < zone->zone_start_pfn); 5164 VM_BUG_ON(pfn >= zone->zone_start_pfn + zone->spanned_pages); 5165 5166 for (; start_bitidx <= end_bitidx; start_bitidx++, value <<= 1) 5167 if (flags & value) 5168 __set_bit(bitidx + start_bitidx, bitmap); 5169 else 5170 __clear_bit(bitidx + start_bitidx, bitmap); 5171} 5172 5173/* 5174 * This is designed as sub function...plz see page_isolation.c also. 5175 * set/clear page block's type to be ISOLATE. 5176 * page allocater never alloc memory from ISOLATE block. 5177 */ 5178 5179int set_migratetype_isolate(struct page *page) 5180{ 5181 struct zone *zone; 5182 struct page *curr_page; 5183 unsigned long flags, pfn, iter; 5184 unsigned long immobile = 0; 5185 struct memory_isolate_notify arg; 5186 int notifier_ret; 5187 int ret = -EBUSY; 5188 int zone_idx; 5189 5190 zone = page_zone(page); 5191 zone_idx = zone_idx(zone); 5192 5193 spin_lock_irqsave(&zone->lock, flags); 5194 if (get_pageblock_migratetype(page) == MIGRATE_MOVABLE || 5195 zone_idx == ZONE_MOVABLE) { 5196 ret = 0; 5197 goto out; 5198 } 5199 5200 pfn = page_to_pfn(page); 5201 arg.start_pfn = pfn; 5202 arg.nr_pages = pageblock_nr_pages; 5203 arg.pages_found = 0; 5204 5205 /* 5206 * It may be possible to isolate a pageblock even if the 5207 * migratetype is not MIGRATE_MOVABLE. The memory isolation 5208 * notifier chain is used by balloon drivers to return the 5209 * number of pages in a range that are held by the balloon 5210 * driver to shrink memory. If all the pages are accounted for 5211 * by balloons, are free, or on the LRU, isolation can continue. 5212 * Later, for example, when memory hotplug notifier runs, these 5213 * pages reported as "can be isolated" should be isolated(freed) 5214 * by the balloon driver through the memory notifier chain. 5215 */ 5216 notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg); 5217 notifier_ret = notifier_to_errno(notifier_ret); 5218 if (notifier_ret || !arg.pages_found) 5219 goto out; 5220 5221 for (iter = pfn; iter < (pfn + pageblock_nr_pages); iter++) { 5222 if (!pfn_valid_within(pfn)) 5223 continue; 5224 5225 curr_page = pfn_to_page(iter); 5226 if (!page_count(curr_page) || PageLRU(curr_page)) 5227 continue; 5228 5229 immobile++; 5230 } 5231 5232 if (arg.pages_found == immobile) 5233 ret = 0; 5234 5235out: 5236 if (!ret) { 5237 set_pageblock_migratetype(page, MIGRATE_ISOLATE); 5238 move_freepages_block(zone, page, MIGRATE_ISOLATE); 5239 } 5240 5241 spin_unlock_irqrestore(&zone->lock, flags); 5242 if (!ret) 5243 drain_all_pages(); 5244 return ret; 5245} 5246 5247void unset_migratetype_isolate(struct page *page) 5248{ 5249 struct zone *zone; 5250 unsigned long flags; 5251 zone = page_zone(page); 5252 spin_lock_irqsave(&zone->lock, flags); 5253 if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE) 5254 goto out; 5255 set_pageblock_migratetype(page, MIGRATE_MOVABLE); 5256 move_freepages_block(zone, page, MIGRATE_MOVABLE); 5257out: 5258 spin_unlock_irqrestore(&zone->lock, flags); 5259} 5260 5261#ifdef CONFIG_MEMORY_HOTREMOVE 5262/* 5263 * All pages in the range must be isolated before calling this. 5264 */ 5265void 5266__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) 5267{ 5268 struct page *page; 5269 struct zone *zone; 5270 int order, i; 5271 unsigned long pfn; 5272 unsigned long flags; 5273 /* find the first valid pfn */ 5274 for (pfn = start_pfn; pfn < end_pfn; pfn++) 5275 if (pfn_valid(pfn)) 5276 break; 5277 if (pfn == end_pfn) 5278 return; 5279 zone = page_zone(pfn_to_page(pfn)); 5280 spin_lock_irqsave(&zone->lock, flags); 5281 pfn = start_pfn; 5282 while (pfn < end_pfn) { 5283 if (!pfn_valid(pfn)) { 5284 pfn++; 5285 continue; 5286 } 5287 page = pfn_to_page(pfn); 5288 BUG_ON(page_count(page)); 5289 BUG_ON(!PageBuddy(page)); 5290 order = page_order(page); 5291#ifdef CONFIG_DEBUG_VM 5292 printk(KERN_INFO "remove from free list %lx %d %lx\n", 5293 pfn, 1 << order, end_pfn); 5294#endif 5295 list_del(&page->lru); 5296 rmv_page_order(page); 5297 zone->free_area[order].nr_free--; 5298 __mod_zone_page_state(zone, NR_FREE_PAGES, 5299 - (1UL << order)); 5300 for (i = 0; i < (1 << order); i++) 5301 SetPageReserved((page+i)); 5302 pfn += (1 << order); 5303 } 5304 spin_unlock_irqrestore(&zone->lock, flags); 5305} 5306#endif 5307 5308#ifdef CONFIG_MEMORY_FAILURE 5309bool is_free_buddy_page(struct page *page) 5310{ 5311 struct zone *zone = page_zone(page); 5312 unsigned long pfn = page_to_pfn(page); 5313 unsigned long flags; 5314 int order; 5315 5316 spin_lock_irqsave(&zone->lock, flags); 5317 for (order = 0; order < MAX_ORDER; order++) { 5318 struct page *page_head = page - (pfn & ((1 << order) - 1)); 5319 5320 if (PageBuddy(page_head) && page_order(page_head) >= order) 5321 break; 5322 } 5323 spin_unlock_irqrestore(&zone->lock, flags); 5324 5325 return order < MAX_ORDER; 5326} 5327#endif 5328 5329static struct trace_print_flags pageflag_names[] = { 5330 {1UL << PG_locked, "locked" }, 5331 {1UL << PG_error, "error" }, 5332 {1UL << PG_referenced, "referenced" }, 5333 {1UL << PG_uptodate, "uptodate" }, 5334 {1UL << PG_dirty, "dirty" }, 5335 {1UL << PG_lru, "lru" }, 5336 {1UL << PG_active, "active" }, 5337 {1UL << PG_slab, "slab" }, 5338 {1UL << PG_owner_priv_1, "owner_priv_1" }, 5339 {1UL << PG_arch_1, "arch_1" }, 5340 {1UL << PG_reserved, "reserved" }, 5341 {1UL << PG_private, "private" }, 5342 {1UL << PG_private_2, "private_2" }, 5343 {1UL << PG_writeback, "writeback" }, 5344#ifdef CONFIG_PAGEFLAGS_EXTENDED 5345 {1UL << PG_head, "head" }, 5346 {1UL << PG_tail, "tail" }, 5347#else 5348 {1UL << PG_compound, "compound" }, 5349#endif 5350 {1UL << PG_swapcache, "swapcache" }, 5351 {1UL << PG_mappedtodisk, "mappedtodisk" }, 5352 {1UL << PG_reclaim, "reclaim" }, 5353 {1UL << PG_buddy, "buddy" }, 5354 {1UL << PG_swapbacked, "swapbacked" }, 5355 {1UL << PG_unevictable, "unevictable" }, 5356#ifdef CONFIG_MMU 5357 {1UL << PG_mlocked, "mlocked" }, 5358#endif 5359#ifdef CONFIG_ARCH_USES_PG_UNCACHED 5360 {1UL << PG_uncached, "uncached" }, 5361#endif 5362#ifdef CONFIG_MEMORY_FAILURE 5363 {1UL << PG_hwpoison, "hwpoison" }, 5364#endif 5365 {-1UL, NULL }, 5366}; 5367 5368static void dump_page_flags(unsigned long flags) 5369{ 5370 const char *delim = ""; 5371 unsigned long mask; 5372 int i; 5373 5374 printk(KERN_ALERT "page flags: %#lx(", flags); 5375 5376 /* remove zone id */ 5377 flags &= (1UL << NR_PAGEFLAGS) - 1; 5378 5379 for (i = 0; pageflag_names[i].name && flags; i++) { 5380 5381 mask = pageflag_names[i].mask; 5382 if ((flags & mask) != mask) 5383 continue; 5384 5385 flags &= ~mask; 5386 printk("%s%s", delim, pageflag_names[i].name); 5387 delim = "|"; 5388 } 5389 5390 /* check for left over flags */ 5391 if (flags) 5392 printk("%s%#lx", delim, flags); 5393 5394 printk(")\n"); 5395} 5396 5397void dump_page(struct page *page) 5398{ 5399 printk(KERN_ALERT 5400 "page:%p count:%d mapcount:%d mapping:%p index:%#lx\n", 5401 page, page_count(page), page_mapcount(page), 5402 page->mapping, page->index); 5403 dump_page_flags(page->flags); 5404} 5405