diff options
Diffstat (limited to 'mm/page_alloc.c')
-rw-r--r-- | mm/page_alloc.c | 353 |
1 files changed, 212 insertions, 141 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index fab5e97dc9ca..23f5066bd4a5 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -69,6 +69,7 @@ #include <linux/nmi.h> #include <linux/psi.h> #include <linux/padata.h> +#include <linux/khugepaged.h> #include <asm/sections.h> #include <asm/tlbflush.h> @@ -77,6 +78,34 @@ #include "shuffle.h" #include "page_reporting.h" +/* Free Page Internal flags: for internal, non-pcp variants of free_pages(). */ +typedef int __bitwise fpi_t; + +/* No special request */ +#define FPI_NONE ((__force fpi_t)0) + +/* + * Skip free page reporting notification for the (possibly merged) page. + * This does not hinder free page reporting from grabbing the page, + * reporting it and marking it "reported" - it only skips notifying + * the free page reporting infrastructure about a newly freed page. For + * example, used when temporarily pulling a page from a freelist and + * putting it back unmodified. + */ +#define FPI_SKIP_REPORT_NOTIFY ((__force fpi_t)BIT(0)) + +/* + * Place the (possibly merged) page to the tail of the freelist. Will ignore + * page shuffling (relevant code - e.g., memory onlining - is expected to + * shuffle the whole zone). + * + * Note: No code should rely on this flag for correctness - it's purely + * to allow for optimizations when handing back either fresh pages + * (memory onlining) or untouched pages (page isolation, free page + * reporting). + */ +#define FPI_TO_TAIL ((__force fpi_t)BIT(1)) + /* prevent >1 _updater_ of zone percpu pageset ->high and ->batch fields */ static DEFINE_MUTEX(pcp_batch_high_lock); #define MIN_PERCPU_PAGELIST_FRACTION (8) @@ -155,16 +184,16 @@ static int __init early_init_on_alloc(char *buf) int ret; bool bool_result; - if (!buf) - return -EINVAL; ret = kstrtobool(buf, &bool_result); + if (ret) + return ret; if (bool_result && page_poisoning_enabled()) pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_alloc\n"); if (bool_result) static_branch_enable(&init_on_alloc); else static_branch_disable(&init_on_alloc); - return ret; + return 0; } early_param("init_on_alloc", early_init_on_alloc); @@ -173,16 +202,16 @@ static int __init early_init_on_free(char *buf) int ret; bool bool_result; - if (!buf) - return -EINVAL; ret = kstrtobool(buf, &bool_result); + if (ret) + return ret; if (bool_result && page_poisoning_enabled()) pr_info("mem auto-init: CONFIG_PAGE_POISONING is on, will take precedence over init_on_free\n"); if (bool_result) static_branch_enable(&init_on_free); else static_branch_disable(&init_on_free); - return ret; + return 0; } early_param("init_on_free", early_init_on_free); @@ -246,7 +275,8 @@ bool pm_suspended_storage(void) unsigned int pageblock_order __read_mostly; #endif -static void __free_pages_ok(struct page *page, unsigned int order); +static void __free_pages_ok(struct page *page, unsigned int order, + fpi_t fpi_flags); /* * results with 256, 32 in the lowmem_reserve sysctl: @@ -658,7 +688,7 @@ out: void free_compound_page(struct page *page) { mem_cgroup_uncharge(page); - __free_pages_ok(page, compound_order(page)); + __free_pages_ok(page, compound_order(page), FPI_NONE); } void prep_compound_page(struct page *page, unsigned int order) @@ -762,7 +792,7 @@ static inline void clear_page_guard(struct zone *zone, struct page *page, unsigned int order, int migratetype) {} #endif -static inline void set_page_order(struct page *page, unsigned int order) +static inline void set_buddy_order(struct page *page, unsigned int order) { set_page_private(page, order); __SetPageBuddy(page); @@ -787,7 +817,7 @@ static inline bool page_is_buddy(struct page *page, struct page *buddy, if (!page_is_guard(buddy) && !PageBuddy(buddy)) return false; - if (page_order(buddy) != order) + if (buddy_order(buddy) != order) return false; /* @@ -872,13 +902,17 @@ static inline void add_to_free_list_tail(struct page *page, struct zone *zone, area->nr_free++; } -/* Used for pages which are on another list */ +/* + * Used for pages which are on another list. Move the pages to the tail + * of the list - so the moved pages won't immediately be considered for + * allocation again (e.g., optimization for memory onlining). + */ static inline void move_to_free_list(struct page *page, struct zone *zone, unsigned int order, int migratetype) { struct free_area *area = &zone->free_area[order]; - list_move(&page->lru, &area->free_list[migratetype]); + list_move_tail(&page->lru, &area->free_list[migratetype]); } static inline void del_page_from_free_list(struct page *page, struct zone *zone, @@ -951,7 +985,7 @@ buddy_merge_likely(unsigned long pfn, unsigned long buddy_pfn, static inline void __free_one_page(struct page *page, unsigned long pfn, struct zone *zone, unsigned int order, - int migratetype, bool report) + int migratetype, fpi_t fpi_flags) { struct capture_control *capc = task_capc(zone); unsigned long buddy_pfn; @@ -1025,9 +1059,11 @@ continue_merging: } done_merging: - set_page_order(page, order); + set_buddy_order(page, order); - if (is_shuffle_order(order)) + if (fpi_flags & FPI_TO_TAIL) + to_tail = true; + else if (is_shuffle_order(order)) to_tail = shuffle_pick_tail(); else to_tail = buddy_merge_likely(pfn, buddy_pfn, page, order); @@ -1038,7 +1074,7 @@ done_merging: add_to_free_list(page, zone, order, migratetype); /* Notify page reporting subsystem of freed page */ - if (report) + if (!(fpi_flags & FPI_SKIP_REPORT_NOTIFY)) page_reporting_notify_free(order); } @@ -1173,6 +1209,17 @@ static __always_inline bool free_pages_prepare(struct page *page, trace_mm_page_free(page, order); + if (unlikely(PageHWPoison(page)) && !order) { + /* + * Do not let hwpoison pages hit pcplists/buddy + * Untie memcg state and reset page's owner + */ + if (memcg_kmem_enabled() && PageKmemcg(page)) + __memcg_kmem_uncharge_page(page, order); + reset_page_owner(page, order); + return false; + } + /* * Check tail pages before head page information is cleared to * avoid checking PageCompound for order-0 pages. @@ -1368,7 +1415,7 @@ static void free_pcppages_bulk(struct zone *zone, int count, if (unlikely(isolated_pageblocks)) mt = get_pageblock_migratetype(page); - __free_one_page(page, page_to_pfn(page), zone, 0, mt, true); + __free_one_page(page, page_to_pfn(page), zone, 0, mt, FPI_NONE); trace_mm_page_pcpu_drain(page, 0, mt); } spin_unlock(&zone->lock); @@ -1377,14 +1424,14 @@ static void free_pcppages_bulk(struct zone *zone, int count, static void free_one_page(struct zone *zone, struct page *page, unsigned long pfn, unsigned int order, - int migratetype) + int migratetype, fpi_t fpi_flags) { spin_lock(&zone->lock); if (unlikely(has_isolate_pageblock(zone) || is_migrate_isolate(migratetype))) { migratetype = get_pfnblock_migratetype(page, pfn); } - __free_one_page(page, pfn, zone, order, migratetype, true); + __free_one_page(page, pfn, zone, order, migratetype, fpi_flags); spin_unlock(&zone->lock); } @@ -1462,7 +1509,8 @@ void __meminit reserve_bootmem_region(phys_addr_t start, phys_addr_t end) } } -static void __free_pages_ok(struct page *page, unsigned int order) +static void __free_pages_ok(struct page *page, unsigned int order, + fpi_t fpi_flags) { unsigned long flags; int migratetype; @@ -1474,7 +1522,8 @@ static void __free_pages_ok(struct page *page, unsigned int order) migratetype = get_pfnblock_migratetype(page, pfn); local_irq_save(flags); __count_vm_events(PGFREE, 1 << order); - free_one_page(page_zone(page), page, pfn, order, migratetype); + free_one_page(page_zone(page), page, pfn, order, migratetype, + fpi_flags); local_irq_restore(flags); } @@ -1484,6 +1533,11 @@ void __free_pages_core(struct page *page, unsigned int order) struct page *p = page; unsigned int loop; + /* + * When initializing the memmap, __init_single_page() sets the refcount + * of all pages to 1 ("allocated"/"not free"). We have to set the + * refcount of all involved pages to 0. + */ prefetchw(p); for (loop = 0; loop < (nr_pages - 1); loop++, p++) { prefetchw(p + 1); @@ -1494,8 +1548,12 @@ void __free_pages_core(struct page *page, unsigned int order) set_page_count(p, 0); atomic_long_add(nr_pages, &page_zone(page)->managed_pages); - set_page_refcounted(page); - __free_pages(page, order); + + /* + * Bypass PCP and place fresh pages right to the tail, primarily + * relevant for memory onlining. + */ + __free_pages_ok(page, order, FPI_TO_TAIL); } #ifdef CONFIG_NEED_MULTIPLE_NODES @@ -2120,7 +2178,7 @@ static inline void expand(struct zone *zone, struct page *page, continue; add_to_free_list(&page[size], zone, high, migratetype); - set_page_order(&page[size], high); + set_buddy_order(&page[size], high); } } @@ -2298,7 +2356,7 @@ static inline struct page *__rmqueue_cma_fallback(struct zone *zone, #endif /* - * Move the free pages in a range to the free lists of the requested type. + * Move the free pages in a range to the freelist tail of the requested type. * Note that start_page and end_pages are not aligned on a pageblock * boundary. If alignment is required, use move_freepages_block() */ @@ -2334,7 +2392,7 @@ static int move_freepages(struct zone *zone, VM_BUG_ON_PAGE(page_to_nid(page) != zone_to_nid(zone), page); VM_BUG_ON_PAGE(page_zone(page) != zone, page); - order = page_order(page); + order = buddy_order(page); move_to_free_list(page, zone, order, migratetype); page += 1 << order; pages_moved += 1 << order; @@ -2458,7 +2516,7 @@ static inline void boost_watermark(struct zone *zone) static void steal_suitable_fallback(struct zone *zone, struct page *page, unsigned int alloc_flags, int start_type, bool whole_block) { - unsigned int current_order = page_order(page); + unsigned int current_order = buddy_order(page); int free_pages, movable_pages, alike_pages; int old_block_type; @@ -3122,7 +3180,8 @@ static void free_unref_page_commit(struct page *page, unsigned long pfn) */ if (migratetype >= MIGRATE_PCPTYPES) { if (unlikely(is_migrate_isolate(migratetype))) { - free_one_page(zone, page, pfn, 0, migratetype); + free_one_page(zone, page, pfn, 0, migratetype, + FPI_NONE); return; } migratetype = MIGRATE_MOVABLE; @@ -3208,7 +3267,7 @@ void split_page(struct page *page, unsigned int order) for (i = 1; i < (1 << order); i++) set_page_refcounted(page + i); - split_page_owner(page, order); + split_page_owner(page, 1 << order); } EXPORT_SYMBOL_GPL(split_page); @@ -3277,7 +3336,8 @@ void __putback_isolated_page(struct page *page, unsigned int order, int mt) lockdep_assert_held(&zone->lock); /* Return isolated page to tail of freelist. */ - __free_one_page(page, page_to_pfn(page), zone, order, mt, false); + __free_one_page(page, page_to_pfn(page), zone, order, mt, + FPI_SKIP_REPORT_NOTIFY | FPI_TO_TAIL); } /* @@ -3367,9 +3427,16 @@ struct page *rmqueue(struct zone *preferred_zone, struct page *page; if (likely(order == 0)) { - page = rmqueue_pcplist(preferred_zone, zone, gfp_flags, + /* + * MIGRATE_MOVABLE pcplist could have the pages on CMA area and + * we need to skip it when CMA area isn't allowed. + */ + if (!IS_ENABLED(CONFIG_CMA) || alloc_flags & ALLOC_CMA || + migratetype != MIGRATE_MOVABLE) { + page = rmqueue_pcplist(preferred_zone, zone, gfp_flags, migratetype, alloc_flags); - goto out; + goto out; + } } /* @@ -3381,7 +3448,13 @@ struct page *rmqueue(struct zone *preferred_zone, do { page = NULL; - if (alloc_flags & ALLOC_HARDER) { + /* + * order-0 request can reach here when the pcplist is skipped + * due to non-CMA allocation context. HIGHATOMIC area is + * reserved for high-order atomic allocation, so order-0 + * request should skip it. + */ + if (order > 0 && alloc_flags & ALLOC_HARDER) { page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC); if (page) trace_mm_page_alloc_zone_locked(page, order, migratetype); @@ -3482,7 +3555,7 @@ static inline bool __should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) #endif /* CONFIG_FAIL_PAGE_ALLOC */ -static noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) +noinline bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order) { return __should_fail_alloc_page(gfp_mask, order); } @@ -3727,8 +3800,8 @@ retry: */ no_fallback = alloc_flags & ALLOC_NOFRAGMENT; z = ac->preferred_zoneref; - for_next_zone_zonelist_nodemask(zone, z, ac->zonelist, - ac->highest_zoneidx, ac->nodemask) { + for_next_zone_zonelist_nodemask(zone, z, ac->highest_zoneidx, + ac->nodemask) { struct page *page; unsigned long mark; @@ -3972,8 +4045,10 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, * success so it is time to admit defeat. We will skip the OOM killer * because it is very likely that the caller has a more reasonable * fallback than shooting a random task. + * + * The OOM killer may not free memory on a specific node. */ - if (gfp_mask & __GFP_RETRY_MAYFAIL) + if (gfp_mask & (__GFP_RETRY_MAYFAIL | __GFP_THISNODE)) goto out; /* The OOM killer does not needlessly kill tasks for lowmem */ if (ac->highest_zoneidx < ZONE_NORMAL) @@ -3990,10 +4065,6 @@ __alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order, * failures more gracefully we should just bail out here. */ - /* The OOM killer may not free memory on a specific node */ - if (gfp_mask & __GFP_THISNODE) - goto out; - /* Exhausted what can be done so it's blame time */ if (out_of_memory(&oc) || WARN_ON_ONCE(gfp_mask & __GFP_NOFAIL)) { *did_some_progress = 1; @@ -4241,13 +4312,12 @@ EXPORT_SYMBOL_GPL(fs_reclaim_release); #endif /* Perform direct synchronous page reclaim */ -static int +static unsigned long __perform_reclaim(gfp_t gfp_mask, unsigned int order, const struct alloc_context *ac) { - int progress; unsigned int noreclaim_flag; - unsigned long pflags; + unsigned long pflags, progress; cond_resched(); @@ -4826,12 +4896,6 @@ static inline bool prepare_alloc_pages(gfp_t gfp_mask, unsigned int order, *alloc_flags = current_alloc_flags(gfp_mask, *alloc_flags); - return true; -} - -/* Determine whether to spread dirty pages and what the first usable zone */ -static inline void finalise_ac(gfp_t gfp_mask, struct alloc_context *ac) -{ /* Dirty zone balancing only done in the fast path */ ac->spread_dirty_pages = (gfp_mask & __GFP_WRITE); @@ -4842,6 +4906,8 @@ static inline void finalise_ac(gfp_t gfp_mask, struct alloc_context *ac) */ ac->preferred_zoneref = first_zones_zonelist(ac->zonelist, ac->highest_zoneidx, ac->nodemask); + + return true; } /* @@ -4870,8 +4936,6 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order, int preferred_nid, if (!prepare_alloc_pages(gfp_mask, order, preferred_nid, nodemask, &ac, &alloc_mask, &alloc_flags)) return NULL; - finalise_ac(gfp_mask, &ac); - /* * Forbid the first pass from falling back to types that fragment * memory until all local zones are considered. @@ -4940,13 +5004,16 @@ static inline void free_the_page(struct page *page, unsigned int order) if (order == 0) /* Via pcp? */ free_unref_page(page); else - __free_pages_ok(page, order); + __free_pages_ok(page, order, FPI_NONE); } void __free_pages(struct page *page, unsigned int order) { if (put_page_testzero(page)) free_the_page(page, order); + else if (!PageHead(page)) + while (order-- > 0) + free_the_page(page + (1 << order), order); } EXPORT_SYMBOL(__free_pages); @@ -5637,7 +5704,6 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask) int n, val; int min_val = INT_MAX; int best_node = NUMA_NO_NODE; - const struct cpumask *tmp = cpumask_of_node(0); /* Use the local node if we haven't already */ if (!node_isset(node, *used_node_mask)) { @@ -5658,8 +5724,7 @@ static int find_next_best_node(int node, nodemask_t *used_node_mask) val += (n < node); /* Give preference to headless and unused nodes */ - tmp = cpumask_of_node(n); - if (!cpumask_empty(tmp)) + if (!cpumask_empty(cpumask_of_node(n))) val += PENALTY_FOR_NODE_WITH_CPUS; /* Slight preference for less loaded node */ @@ -5955,7 +6020,7 @@ overlap_memmap_init(unsigned long zone, unsigned long *pfn) if (mirrored_kernelcore && zone == ZONE_MOVABLE) { if (!r || *pfn >= memblock_region_memory_end_pfn(r)) { - for_each_memblock(memory, r) { + for_each_mem_region(r) { if (*pfn < memblock_region_memory_end_pfn(r)) break; } @@ -5973,10 +6038,15 @@ overlap_memmap_init(unsigned long zone, unsigned long *pfn) * Initially all pages are reserved - free ones are freed * up by memblock_free_all() once the early boot process is * done. Non-atomic initialization, single-pass. + * + * All aligned pageblocks are initialized to the specified migratetype + * (usually MIGRATE_MOVABLE). Besides setting the migratetype, no related + * zone stats (e.g., nr_isolate_pageblock) are touched. */ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, - unsigned long start_pfn, enum memmap_context context, - struct vmem_altmap *altmap) + unsigned long start_pfn, + enum meminit_context context, + struct vmem_altmap *altmap, int migratetype) { unsigned long pfn, end_pfn = start_pfn + size; struct page *page; @@ -6007,7 +6077,7 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, * There can be holes in boot-time mem_map[]s handed to this * function. They do not exist on hotplugged memory. */ - if (context == MEMMAP_EARLY) { + if (context == MEMINIT_EARLY) { if (overlap_memmap_init(zone, &pfn)) continue; if (defer_init(nid, pfn, end_pfn)) @@ -6016,23 +6086,16 @@ void __meminit memmap_init_zone(unsigned long size, int nid, unsigned long zone, page = pfn_to_page(pfn); __init_single_page(page, pfn, zone, nid); - if (context == MEMMAP_HOTPLUG) + if (context == MEMINIT_HOTPLUG) __SetPageReserved(page); /* - * Mark the block movable so that blocks are reserved for - * movable at startup. This will force kernel allocations - * to reserve their blocks rather than leaking throughout - * the address space during boot when many long-lived - * kernel allocations are made. - * - * bitmap is created for zone's valid pfn range. but memmap - * can be created for invalid pages (for alignment) - * check here not to call set_pageblock_migratetype() against - * pfn out of zone. + * Usually, we want to mark the pageblock MIGRATE_MOVABLE, + * such that unmovable allocations won't be scattered all + * over the place during system boot. */ - if (!(pfn & (pageblock_nr_pages - 1))) { - set_pageblock_migratetype(page, MIGRATE_MOVABLE); + if (IS_ALIGNED(pfn, pageblock_nr_pages)) { + set_pageblock_migratetype(page, migratetype); cond_resched(); } pfn++; @@ -6094,15 +6157,10 @@ void __ref memmap_init_zone_device(struct zone *zone, * the address space during boot when many long-lived * kernel allocations are made. * - * bitmap is created for zone's valid pfn range. but memmap - * can be created for invalid pages (for alignment) - * check here not to call set_pageblock_migratetype() against - * pfn out of zone. - * - * Please note that MEMMAP_HOTPLUG path doesn't clear memmap + * Please note that MEMINIT_HOTPLUG path doesn't clear memmap * because this is done early in section_activate() */ - if (!(pfn & (pageblock_nr_pages - 1))) { + if (IS_ALIGNED(pfn, pageblock_nr_pages)) { set_pageblock_migratetype(page, MIGRATE_MOVABLE); cond_resched(); } @@ -6137,7 +6195,7 @@ void __meminit __weak memmap_init(unsigned long size, int nid, if (end_pfn > start_pfn) { size = end_pfn - start_pfn; memmap_init_zone(size, nid, zone, start_pfn, - MEMMAP_EARLY, NULL); + MEMINIT_EARLY, NULL, MIGRATE_MOVABLE); } } } @@ -6540,7 +6598,7 @@ static unsigned long __init zone_absent_pages_in_node(int nid, unsigned long start_pfn, end_pfn; struct memblock_region *r; - for_each_memblock(memory, r) { + for_each_mem_region(r) { start_pfn = clamp(memblock_region_memory_base_pfn(r), zone_start_pfn, zone_end_pfn); end_pfn = clamp(memblock_region_memory_end_pfn(r), @@ -6984,8 +7042,7 @@ static void __init init_unavailable_mem(void) * Loop through unavailable ranges not covered by memblock.memory. */ pgcnt = 0; - for_each_mem_range(i, &memblock.memory, NULL, - NUMA_NO_NODE, MEMBLOCK_NONE, &start, &end, NULL) { + for_each_mem_range(i, &start, &end) { if (next < start) pgcnt += init_unavailable_range(PFN_DOWN(next), PFN_UP(start)); @@ -7135,7 +7192,7 @@ static void __init find_zone_movable_pfns_for_nodes(void) * options. */ if (movable_node_is_enabled()) { - for_each_memblock(memory, r) { + for_each_mem_region(r) { if (!memblock_is_hotpluggable(r)) continue; @@ -7156,7 +7213,7 @@ static void __init find_zone_movable_pfns_for_nodes(void) if (mirrored_kernelcore) { bool mem_below_4gb_not_mirrored = false; - for_each_memblock(memory, r) { + for_each_mem_region(r) { if (memblock_is_mirror(r)) continue; @@ -7891,6 +7948,8 @@ int __meminit init_per_zone_wmark_min(void) setup_min_slab_ratio(); #endif + khugepaged_min_free_kbytes_update(); + return 0; } postcore_initcall(init_per_zone_wmark_min) @@ -8218,14 +8277,7 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, { unsigned long iter = 0; unsigned long pfn = page_to_pfn(page); - - /* - * TODO we could make this much more efficient by not checking every - * page in the range if we know all of them are in MOVABLE_ZONE and - * that the movable zone guarantees that pages are migratable but - * the later is not the case right now unfortunatelly. E.g. movablecore - * can still lead to having bootmem allocations in zone_movable. - */ + unsigned long offset = pfn % pageblock_nr_pages; if (is_migrate_cma_page(page)) { /* @@ -8239,12 +8291,18 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, return page; } - for (; iter < pageblock_nr_pages; iter++) { + for (; iter < pageblock_nr_pages - offset; iter++) { if (!pfn_valid_within(pfn + iter)) continue; page = pfn_to_page(pfn + iter); + /* + * Both, bootmem allocations and memory holes are marked + * PG_reserved and are unmovable. We can even have unmovable + * allocations inside ZONE_MOVABLE, for example when + * specifying "movablecore". + */ if (PageReserved(page)) return page; @@ -8286,7 +8344,7 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, */ if (!page_ref_count(page)) { if (PageBuddy(page)) - iter += (1 << page_order(page)) - 1; + iter += (1 << buddy_order(page)) - 1; continue; } @@ -8318,14 +8376,6 @@ struct page *has_unmovable_pages(struct zone *zone, struct page *page, * it. But now, memory offline itself doesn't call * shrink_node_slabs() and it still to be fixed. */ - /* - * If the page is not RAM, page_count()should be 0. - * we don't need more check. This is an _used_ not-movable page. - * - * The problematic thing here is PG_reserved pages. PG_reserved - * is set to both of a memory hole page and a _used_ kernel - * page at boot. - */ return page; } return NULL; @@ -8459,7 +8509,7 @@ int alloc_contig_range(unsigned long start, unsigned long end, ret = start_isolate_page_range(pfn_max_align_down(start), pfn_max_align_up(end), migratetype, 0); - if (ret < 0) + if (ret) return ret; /* @@ -8507,7 +8557,7 @@ int alloc_contig_range(unsigned long start, unsigned long end, } if (outer_start != start) { - order = page_order(pfn_to_page(outer_start)); + order = buddy_order(pfn_to_page(outer_start)); /* * outer_start page could be small order buddy page and @@ -8695,35 +8745,21 @@ void zone_pcp_reset(struct zone *zone) #ifdef CONFIG_MEMORY_HOTREMOVE /* - * All pages in the range must be in a single zone and isolated - * before calling this. + * All pages in the range must be in a single zone, must not contain holes, + * must span full sections, and must be isolated before calling this function. */ -unsigned long -__offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) +void __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) { + unsigned long pfn = start_pfn; struct page *page; struct zone *zone; unsigned int order; - unsigned long pfn; unsigned long flags; - unsigned long offlined_pages = 0; - - /* find the first valid pfn */ - for (pfn = start_pfn; pfn < end_pfn; pfn++) - if (pfn_valid(pfn)) - break; - if (pfn == end_pfn) - return offlined_pages; offline_mem_sections(pfn, end_pfn); zone = page_zone(pfn_to_page(pfn)); spin_lock_irqsave(&zone->lock, flags); - pfn = start_pfn; while (pfn < end_pfn) { - if (!pfn_valid(pfn)) { - pfn++; - continue; - } page = pfn_to_page(pfn); /* * The HWPoisoned page may be not in buddy system, and @@ -8731,7 +8767,6 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) */ if (unlikely(!PageBuddy(page) && PageHWPoison(page))) { pfn++; - offlined_pages++; continue; } /* @@ -8742,20 +8777,16 @@ __offline_isolated_pages(unsigned long start_pfn, unsigned long end_pfn) BUG_ON(page_count(page)); BUG_ON(PageBuddy(page)); pfn++; - offlined_pages++; continue; } BUG_ON(page_count(page)); BUG_ON(!PageBuddy(page)); - order = page_order(page); - offlined_pages += 1 << order; + order = buddy_order(page); del_page_from_free_list(page, zone, order); pfn += (1 << order); } spin_unlock_irqrestore(&zone->lock, flags); - - return offlined_pages; } #endif @@ -8770,7 +8801,7 @@ bool is_free_buddy_page(struct page *page) for (order = 0; order < MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); - if (PageBuddy(page_head) && page_order(page_head) >= order) + if (PageBuddy(page_head) && buddy_order(page_head) >= order) break; } spin_unlock_irqrestore(&zone->lock, flags); @@ -8780,30 +8811,70 @@ bool is_free_buddy_page(struct page *page) #ifdef CONFIG_MEMORY_FAILURE /* - * Set PG_hwpoison flag if a given page is confirmed to be a free page. This - * test is performed under the zone lock to prevent a race against page - * allocation. + * Break down a higher-order page in sub-pages, and keep our target out of + * buddy allocator. */ -bool set_hwpoison_free_buddy_page(struct page *page) +static void break_down_buddy_pages(struct zone *zone, struct page *page, + struct page *target, int low, int high, + int migratetype) +{ + unsigned long size = 1 << high; + struct page *current_buddy, *next_page; + + while (high > low) { + high--; + size >>= 1; + + if (target >= &page[size]) { + next_page = page + size; + current_buddy = page; + } else { + next_page = page; + current_buddy = page + size; + } + + if (set_page_guard(zone, current_buddy, high, migratetype)) + continue; + + if (current_buddy != target) { + add_to_free_list(current_buddy, zone, high, migratetype); + set_buddy_order(current_buddy, high); + page = next_page; + } + } +} + +/* + * Take a page that will be marked as poisoned off the buddy allocator. + */ +bool take_page_off_buddy(struct page *page) { struct zone *zone = page_zone(page); unsigned long pfn = page_to_pfn(page); unsigned long flags; unsigned int order; - bool hwpoisoned = false; + bool ret = false; spin_lock_irqsave(&zone->lock, flags); for (order = 0; order < MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); + int page_order = buddy_order(page_head); + + if (PageBuddy(page_head) && page_order >= order) { + unsigned long pfn_head = page_to_pfn(page_head); + int migratetype = get_pfnblock_migratetype(page_head, + pfn_head); - if (PageBuddy(page_head) && page_order(page_head) >= order) { - if (!TestSetPageHWPoison(page)) - hwpoisoned = true; + del_page_from_free_list(page_head, zone, page_order); + break_down_buddy_pages(zone, page_head, page, 0, + page_order, migratetype); + ret = true; break; } + if (page_count(page_head) > 0) + break; } spin_unlock_irqrestore(&zone->lock, flags); - - return hwpoisoned; + return ret; } #endif |