diff options
Diffstat (limited to 'mm')
-rw-r--r-- | mm/Kconfig | 40 | ||||
-rw-r--r-- | mm/Makefile | 3 | ||||
-rw-r--r-- | mm/compaction.c | 186 | ||||
-rw-r--r-- | mm/dmapool.c | 16 | ||||
-rw-r--r-- | mm/filemap.c | 25 | ||||
-rw-r--r-- | mm/huge_memory.c | 2354 | ||||
-rw-r--r-- | mm/hugetlb.c | 114 | ||||
-rw-r--r-- | mm/internal.h | 7 | ||||
-rw-r--r-- | mm/kmemleak-test.c | 6 | ||||
-rw-r--r-- | mm/kmemleak.c | 13 | ||||
-rw-r--r-- | mm/ksm.c | 88 | ||||
-rw-r--r-- | mm/madvise.c | 10 | ||||
-rw-r--r-- | mm/memblock.c | 10 | ||||
-rw-r--r-- | mm/memcontrol.c | 431 | ||||
-rw-r--r-- | mm/memory-failure.c | 118 | ||||
-rw-r--r-- | mm/memory.c | 360 | ||||
-rw-r--r-- | mm/memory_hotplug.c | 52 | ||||
-rw-r--r-- | mm/mempolicy.c | 26 | ||||
-rw-r--r-- | mm/migrate.c | 134 | ||||
-rw-r--r-- | mm/mincore.c | 7 | ||||
-rw-r--r-- | mm/mlock.c | 170 | ||||
-rw-r--r-- | mm/mmap.c | 33 | ||||
-rw-r--r-- | mm/mmu_notifier.c | 20 | ||||
-rw-r--r-- | mm/mmzone.c | 21 | ||||
-rw-r--r-- | mm/mprotect.c | 20 | ||||
-rw-r--r-- | mm/mremap.c | 9 | ||||
-rw-r--r-- | mm/nommu.c | 35 | ||||
-rw-r--r-- | mm/page-writeback.c | 11 | ||||
-rw-r--r-- | mm/page_alloc.c | 216 | ||||
-rw-r--r-- | mm/pagewalk.c | 6 | ||||
-rw-r--r-- | mm/percpu-vm.c | 2 | ||||
-rw-r--r-- | mm/percpu.c | 12 | ||||
-rw-r--r-- | mm/pgtable-generic.c | 121 | ||||
-rw-r--r-- | mm/rmap.c | 93 | ||||
-rw-r--r-- | mm/shmem.c | 9 | ||||
-rw-r--r-- | mm/slab.c | 82 | ||||
-rw-r--r-- | mm/slob.c | 5 | ||||
-rw-r--r-- | mm/slub.c | 89 | ||||
-rw-r--r-- | mm/sparse-vmemmap.c | 2 | ||||
-rw-r--r-- | mm/sparse.c | 4 | ||||
-rw-r--r-- | mm/swap.c | 131 | ||||
-rw-r--r-- | mm/swap_state.c | 6 | ||||
-rw-r--r-- | mm/swapfile.c | 9 | ||||
-rw-r--r-- | mm/truncate.c | 15 | ||||
-rw-r--r-- | mm/util.c | 21 | ||||
-rw-r--r-- | mm/vmalloc.c | 118 | ||||
-rw-r--r-- | mm/vmscan.c | 435 | ||||
-rw-r--r-- | mm/vmstat.c | 206 |
48 files changed, 4789 insertions, 1112 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index c2c8a4a11898..e9c0c61f2ddd 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -179,7 +179,7 @@ config SPLIT_PTLOCK_CPUS config COMPACTION bool "Allow for memory compaction" select MIGRATION - depends on EXPERIMENTAL && HUGETLB_PAGE && MMU + depends on MMU help Allows the compaction of memory for the allocation of huge pages. @@ -302,6 +302,44 @@ config NOMMU_INITIAL_TRIM_EXCESS See Documentation/nommu-mmap.txt for more information. +config TRANSPARENT_HUGEPAGE + bool "Transparent Hugepage Support" + depends on X86 && MMU + select COMPACTION + help + Transparent Hugepages allows the kernel to use huge pages and + huge tlb transparently to the applications whenever possible. + This feature can improve computing performance to certain + applications by speeding up page faults during memory + allocation, by reducing the number of tlb misses and by speeding + up the pagetable walking. + + If memory constrained on embedded, you may want to say N. + +choice + prompt "Transparent Hugepage Support sysfs defaults" + depends on TRANSPARENT_HUGEPAGE + default TRANSPARENT_HUGEPAGE_ALWAYS + help + Selects the sysfs defaults for Transparent Hugepage Support. + + config TRANSPARENT_HUGEPAGE_ALWAYS + bool "always" + help + Enabling Transparent Hugepage always, can increase the + memory footprint of applications without a guaranteed + benefit but it will work automatically for all applications. + + config TRANSPARENT_HUGEPAGE_MADVISE + bool "madvise" + help + Enabling Transparent Hugepage madvise, will only provide a + performance improvement benefit to the applications using + madvise(MADV_HUGEPAGE) but it won't risk to increase the + memory footprint of applications without a guaranteed + benefit. +endchoice + # # UP and nommu archs use km based percpu allocator # diff --git a/mm/Makefile b/mm/Makefile index f73f75a29f82..2b1b575ae712 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -5,7 +5,7 @@ mmu-y := nommu.o mmu-$(CONFIG_MMU) := fremap.o highmem.o madvise.o memory.o mincore.o \ mlock.o mmap.o mprotect.o mremap.o msync.o rmap.o \ - vmalloc.o pagewalk.o + vmalloc.o pagewalk.o pgtable-generic.o obj-y := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \ maccess.o page_alloc.o page-writeback.o \ @@ -37,6 +37,7 @@ obj-$(CONFIG_MEMORY_HOTPLUG) += memory_hotplug.o obj-$(CONFIG_FS_XIP) += filemap_xip.o obj-$(CONFIG_MIGRATION) += migrate.o obj-$(CONFIG_QUICKLIST) += quicklist.o +obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += huge_memory.o obj-$(CONFIG_CGROUP_MEM_RES_CTLR) += memcontrol.o page_cgroup.o obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o diff --git a/mm/compaction.c b/mm/compaction.c index 4d709ee59013..8be430b812de 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -16,6 +16,9 @@ #include <linux/sysfs.h> #include "internal.h" +#define CREATE_TRACE_POINTS +#include <trace/events/compaction.h> + /* * compact_control is used to track pages being migrated and the free pages * they are being migrated to during memory compaction. The free_pfn starts @@ -30,6 +33,7 @@ struct compact_control { unsigned long nr_migratepages; /* Number of pages to migrate */ unsigned long free_pfn; /* isolate_freepages search base */ unsigned long migrate_pfn; /* isolate_migratepages search base */ + bool sync; /* Synchronous migration */ /* Account for isolated anon and file pages */ unsigned long nr_anon; @@ -38,6 +42,8 @@ struct compact_control { unsigned int order; /* order a direct compactor needs */ int migratetype; /* MOVABLE, RECLAIMABLE etc */ struct zone *zone; + + int compact_mode; }; static unsigned long release_freepages(struct list_head *freelist) @@ -60,7 +66,7 @@ static unsigned long isolate_freepages_block(struct zone *zone, struct list_head *freelist) { unsigned long zone_end_pfn, end_pfn; - int total_isolated = 0; + int nr_scanned = 0, total_isolated = 0; struct page *cursor; /* Get the last PFN we should scan for free pages at */ @@ -81,6 +87,7 @@ static unsigned long isolate_freepages_block(struct zone *zone, if (!pfn_valid_within(blockpfn)) continue; + nr_scanned++; if (!PageBuddy(page)) continue; @@ -100,6 +107,7 @@ static unsigned long isolate_freepages_block(struct zone *zone, } } + trace_mm_compaction_isolate_freepages(nr_scanned, total_isolated); return total_isolated; } @@ -234,6 +242,8 @@ static unsigned long isolate_migratepages(struct zone *zone, struct compact_control *cc) { unsigned long low_pfn, end_pfn; + unsigned long last_pageblock_nr = 0, pageblock_nr; + unsigned long nr_scanned = 0, nr_isolated = 0; struct list_head *migratelist = &cc->migratepages; /* Do not scan outside zone boundaries */ @@ -266,21 +276,51 @@ static unsigned long isolate_migratepages(struct zone *zone, struct page *page; if (!pfn_valid_within(low_pfn)) continue; + nr_scanned++; /* Get the page and skip if free */ page = pfn_to_page(low_pfn); if (PageBuddy(page)) continue; + /* + * For async migration, also only scan in MOVABLE blocks. Async + * migration is optimistic to see if the minimum amount of work + * satisfies the allocation + */ + pageblock_nr = low_pfn >> pageblock_order; + if (!cc->sync && last_pageblock_nr != pageblock_nr && + get_pageblock_migratetype(page) != MIGRATE_MOVABLE) { + low_pfn += pageblock_nr_pages; + low_pfn = ALIGN(low_pfn, pageblock_nr_pages) - 1; + last_pageblock_nr = pageblock_nr; + continue; + } + + if (!PageLRU(page)) + continue; + + /* + * PageLRU is set, and lru_lock excludes isolation, + * splitting and collapsing (collapsing has already + * happened if PageLRU is set). + */ + if (PageTransHuge(page)) { + low_pfn += (1 << compound_order(page)) - 1; + continue; + } + /* Try isolate the page */ if (__isolate_lru_page(page, ISOLATE_BOTH, 0) != 0) continue; + VM_BUG_ON(PageTransCompound(page)); + /* Successfully isolated */ del_page_from_lru_list(zone, page, page_lru(page)); list_add(&page->lru, migratelist); - mem_cgroup_del_lru(page); cc->nr_migratepages++; + nr_isolated++; /* Avoid isolating too much */ if (cc->nr_migratepages == COMPACT_CLUSTER_MAX) @@ -292,6 +332,8 @@ static unsigned long isolate_migratepages(struct zone *zone, spin_unlock_irq(&zone->lru_lock); cc->migrate_pfn = low_pfn; + trace_mm_compaction_isolate_migratepages(nr_scanned, nr_isolated); + return cc->nr_migratepages; } @@ -342,10 +384,10 @@ static void update_nr_listpages(struct compact_control *cc) } static int compact_finished(struct zone *zone, - struct compact_control *cc) + struct compact_control *cc) { unsigned int order; - unsigned long watermark = low_wmark_pages(zone) + (1 << cc->order); + unsigned long watermark; if (fatal_signal_pending(current)) return COMPACT_PARTIAL; @@ -355,12 +397,31 @@ static int compact_finished(struct zone *zone, return COMPACT_COMPLETE; /* Compaction run is not finished if the watermark is not met */ + if (cc->compact_mode != COMPACT_MODE_KSWAPD) + watermark = low_wmark_pages(zone); + else + watermark = high_wmark_pages(zone); + watermark += (1 << cc->order); + if (!zone_watermark_ok(zone, cc->order, watermark, 0, 0)) return COMPACT_CONTINUE; + /* + * order == -1 is expected when compacting via + * /proc/sys/vm/compact_memory + */ if (cc->order == -1) return COMPACT_CONTINUE; + /* + * Generating only one page of the right order is not enough + * for kswapd, we must continue until we're above the high + * watermark as a pool for high order GFP_ATOMIC allocations + * too. + */ + if (cc->compact_mode == COMPACT_MODE_KSWAPD) + return COMPACT_CONTINUE; + /* Direct compactor: Is a suitable page free? */ for (order = cc->order; order < MAX_ORDER; order++) { /* Job done if page is free of the right migratetype */ @@ -375,10 +436,69 @@ static int compact_finished(struct zone *zone, return COMPACT_CONTINUE; } +/* + * compaction_suitable: Is this suitable to run compaction on this zone now? + * Returns + * COMPACT_SKIPPED - If there are too few free pages for compaction + * COMPACT_PARTIAL - If the allocation would succeed without compaction + * COMPACT_CONTINUE - If compaction should run now + */ +unsigned long compaction_suitable(struct zone *zone, int order) +{ + int fragindex; + unsigned long watermark; + + /* + * Watermarks for order-0 must be met for compaction. Note the 2UL. + * This is because during migration, copies of pages need to be + * allocated and for a short time, the footprint is higher + */ + watermark = low_wmark_pages(zone) + (2UL << order); + if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) + return COMPACT_SKIPPED; + + /* + * order == -1 is expected when compacting via + * /proc/sys/vm/compact_memory + */ + if (order == -1) + return COMPACT_CONTINUE; + + /* + * fragmentation index determines if allocation failures are due to + * low memory or external fragmentation + * + * index of -1 implies allocations might succeed dependingon watermarks + * index towards 0 implies failure is due to lack of memory + * index towards 1000 implies failure is due to fragmentation + * + * Only compact if a failure would be due to fragmentation. + */ + fragindex = fragmentation_index(zone, order); + if (fragindex >= 0 && fragindex <= sysctl_extfrag_threshold) + return COMPACT_SKIPPED; + + if (fragindex == -1 && zone_watermark_ok(zone, order, watermark, 0, 0)) + return COMPACT_PARTIAL; + + return COMPACT_CONTINUE; +} + static int compact_zone(struct zone *zone, struct compact_control *cc) { int ret; + ret = compaction_suitable(zone, cc->order); + switch (ret) { + case COMPACT_PARTIAL: + case COMPACT_SKIPPED: + /* Compaction is likely to fail */ + return ret; + case COMPACT_CONTINUE: + /* Fall through to compaction */ + ; + } + /* Setup to move all movable pages to the end of the zone */ cc->migrate_pfn = zone->zone_start_pfn; cc->free_pfn = cc->migrate_pfn + zone->spanned_pages; @@ -394,7 +514,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) nr_migrate = cc->nr_migratepages; migrate_pages(&cc->migratepages, compaction_alloc, - (unsigned long)cc, 0); + (unsigned long)cc, false, + cc->sync); update_nr_listpages(cc); nr_remaining = cc->nr_migratepages; @@ -402,6 +523,8 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) count_vm_events(COMPACTPAGES, nr_migrate - nr_remaining); if (nr_remaining) count_vm_events(COMPACTPAGEFAILED, nr_remaining); + trace_mm_compaction_migratepages(nr_migrate - nr_remaining, + nr_remaining); /* Release LRU pages not migrated */ if (!list_empty(&cc->migratepages)) { @@ -418,8 +541,10 @@ static int compact_zone(struct zone *zone, struct compact_control *cc) return ret; } -static unsigned long compact_zone_order(struct zone *zone, - int order, gfp_t gfp_mask) +unsigned long compact_zone_order(struct zone *zone, + int order, gfp_t gfp_mask, + bool sync, + int compact_mode) { struct compact_control cc = { .nr_freepages = 0, @@ -427,6 +552,8 @@ static unsigned long compact_zone_order(struct zone *zone, .order = order, .migratetype = allocflags_to_migratetype(gfp_mask), .zone = zone, + .sync = sync, + .compact_mode = compact_mode, }; INIT_LIST_HEAD(&cc.freepages); INIT_LIST_HEAD(&cc.migratepages); @@ -442,16 +569,17 @@ int sysctl_extfrag_threshold = 500; * @order: The order of the current allocation * @gfp_mask: The GFP mask of the current allocation * @nodemask: The allowed nodes to allocate from + * @sync: Whether migration is synchronous or not * * This is the main entry point for direct page compaction. */ unsigned long try_to_compact_pages(struct zonelist *zonelist, - int order, gfp_t gfp_mask, nodemask_t *nodemask) + int order, gfp_t gfp_mask, nodemask_t *nodemask, + bool sync) { enum zone_type high_zoneidx = gfp_zone(gfp_mask); int may_enter_fs = gfp_mask & __GFP_FS; int may_perform_io = gfp_mask & __GFP_IO; - unsigned long watermark; struct zoneref *z; struct zone *zone; int rc = COMPACT_SKIPPED; @@ -461,7 +589,7 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, * made because an assumption is made that the page allocator can satisfy * the "cheaper" orders without taking special steps */ - if (order <= PAGE_ALLOC_COSTLY_ORDER || !may_enter_fs || !may_perform_io) + if (!order || !may_enter_fs || !may_perform_io) return rc; count_vm_event(COMPACTSTALL); @@ -469,43 +597,14 @@ unsigned long try_to_compact_pages(struct zonelist *zonelist, /* Compact each zone in the list */ for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx, nodemask) { - int fragindex; int status; - /* - * Watermarks for order-0 must be met for compaction. Note - * the 2UL. This is because during migration, copies of - * pages need to be allocated and for a short time, the - * footprint is higher - */ - watermark = low_wmark_pages(zone) + (2UL << order); - if (!zone_watermark_ok(zone, 0, watermark, 0, 0)) - continue; - - /* - * fragmentation index determines if allocation failures are - * due to low memory or external fragmentation - * - * index of -1 implies allocations might succeed depending - * on watermarks - * index towards 0 implies failure is due to lack of memory - * index towards 1000 implies failure is due to fragmentation - * - * Only compact if a failure would be due to fragmentation. - */ - fragindex = fragmentation_index(zone, order); - if (fragindex >= 0 && fragindex <= sysctl_extfrag_threshold) - continue; - - if (fragindex == -1 && zone_watermark_ok(zone, order, watermark, 0, 0)) { - rc = COMPACT_PARTIAL; - break; - } - - status = compact_zone_order(zone, order, gfp_mask); + status = compact_zone_order(zone, order, gfp_mask, sync, + COMPACT_MODE_DIRECT_RECLAIM); rc = max(status, rc); - if (zone_watermark_ok(zone, order, watermark, 0, 0)) + /* If a normal allocation would succeed, stop compacting */ + if (zone_watermark_ok(zone, order, low_wmark_pages(zone), 0, 0)) break; } @@ -532,6 +631,7 @@ static int compact_node(int nid) .nr_freepages = 0, .nr_migratepages = 0, .order = -1, + .compact_mode = COMPACT_MODE_DIRECT_RECLAIM, }; zone = &pgdat->node_zones[zoneid]; diff --git a/mm/dmapool.c b/mm/dmapool.c index 4df2de77e069..03bf3bb4519a 100644 --- a/mm/dmapool.c +++ b/mm/dmapool.c @@ -324,7 +324,7 @@ void *dma_pool_alloc(struct dma_pool *pool, gfp_t mem_flags, if (mem_flags & __GFP_WAIT) { DECLARE_WAITQUEUE(wait, current); - __set_current_state(TASK_INTERRUPTIBLE); + __set_current_state(TASK_UNINTERRUPTIBLE); __add_wait_queue(&pool->waitq, &wait); spin_unlock_irqrestore(&pool->lock, flags); @@ -355,20 +355,15 @@ EXPORT_SYMBOL(dma_pool_alloc); static struct dma_page *pool_find_page(struct dma_pool *pool, dma_addr_t dma) { - unsigned long flags; struct dma_page *page; - spin_lock_irqsave(&pool->lock, flags); list_for_each_entry(page, &pool->page_list, page_list) { if (dma < page->dma) continue; if (dma < (page->dma + pool->allocation)) - goto done; + return page; } - page = NULL; - done: - spin_unlock_irqrestore(&pool->lock, flags); - return page; + return NULL; } /** @@ -386,8 +381,10 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) unsigned long flags; unsigned int offset; + spin_lock_irqsave(&pool->lock, flags); page = pool_find_page(pool, dma); if (!page) { + spin_unlock_irqrestore(&pool->lock, flags); if (pool->dev) dev_err(pool->dev, "dma_pool_free %s, %p/%lx (bad dma)\n", @@ -401,6 +398,7 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) offset = vaddr - page->vaddr; #ifdef DMAPOOL_DEBUG if ((dma - page->dma) != offset) { + spin_unlock_irqrestore(&pool->lock, flags); if (pool->dev) dev_err(pool->dev, "dma_pool_free %s, %p (bad vaddr)/%Lx\n", @@ -418,6 +416,7 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) chain = *(int *)(page->vaddr + chain); continue; } + spin_unlock_irqrestore(&pool->lock, flags); if (pool->dev) dev_err(pool->dev, "dma_pool_free %s, dma %Lx " "already free\n", pool->name, @@ -432,7 +431,6 @@ void dma_pool_free(struct dma_pool *pool, void *vaddr, dma_addr_t dma) memset(vaddr, POOL_POISON_FREED, pool->size); #endif - spin_lock_irqsave(&pool->lock, flags); page->in_use--; *(int *)vaddr = page->offset; page->offset = offset; diff --git a/mm/filemap.c b/mm/filemap.c index ea89840fc65f..83a45d35468b 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -102,9 +102,6 @@ * ->inode_lock (zap_pte_range->set_page_dirty) * ->private_lock (zap_pte_range->__set_page_dirty_buffers) * - * ->task->proc_lock - * ->dcache_lock (proc_pid_lookup) - * * (code doesn't rely on that order, so you could switch it around) * ->tasklist_lock (memory_failure, collect_procs_ao) * ->i_mmap_lock @@ -143,13 +140,18 @@ void __remove_from_page_cache(struct page *page) void remove_from_page_cache(struct page *page) { struct address_space *mapping = page->mapping; + void (*freepage)(struct page *); BUG_ON(!PageLocked(page)); + freepage = mapping->a_ops->freepage; spin_lock_irq(&mapping->tree_lock); __remove_from_page_cache(page); spin_unlock_irq(&mapping->tree_lock); mem_cgroup_uncharge_cache_page(page); + + if (freepage) + freepage(page); } EXPORT_SYMBOL(remove_from_page_cache); @@ -296,7 +298,7 @@ int filemap_fdatawait_range(struct address_space *mapping, loff_t start_byte, continue; wait_on_page_writeback(page); - if (PageError(page)) + if (TestClearPageError(page)) ret = -EIO; } pagevec_release(&pvec); @@ -835,9 +837,6 @@ repeat: if (radix_tree_deref_retry(page)) goto restart; - if (page->mapping == NULL || page->index != index) - break; - if (!page_cache_get_speculative(page)) goto repeat; @@ -847,6 +846,16 @@ repeat: goto repeat; } + /* + * must check mapping and index after taking the ref. + * otherwise we can get both false positives and false + * negatives, which is just confusing to the caller. + */ + if (page->mapping == NULL || page->index != index) { + page_cache_release(page); + break; + } + pages[ret] = page; ret++; index++; @@ -2218,7 +2227,7 @@ struct page *grab_cache_page_write_begin(struct address_space *mapping, gfp_notmask = __GFP_FS; repeat: page = find_lock_page(mapping, index); - if (likely(page)) + if (page) return page; page = __page_cache_alloc(mapping_gfp_mask(mapping) & ~gfp_notmask); diff --git a/mm/huge_memory.c b/mm/huge_memory.c new file mode 100644 index 000000000000..e62ddb8f24b6 --- /dev/null +++ b/mm/huge_memory.c @@ -0,0 +1,2354 @@ +/* + * Copyright (C) 2009 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2. See + * the COPYING file in the top-level directory. + */ + +#include <linux/mm.h> +#include <linux/sched.h> +#include <linux/highmem.h> +#include <linux/hugetlb.h> +#include <linux/mmu_notifier.h> +#include <linux/rmap.h> +#include <linux/swap.h> +#include <linux/mm_inline.h> +#include <linux/kthread.h> +#include <linux/khugepaged.h> +#include <linux/freezer.h> +#include <linux/mman.h> +#include <asm/tlb.h> +#include <asm/pgalloc.h> +#include "internal.h" + +/* + * By default transparent hugepage support is enabled for all mappings + * and khugepaged scans all mappings. Defrag is only invoked by + * khugepaged hugepage allocations and by page faults inside + * MADV_HUGEPAGE regions to avoid the risk of slowing down short lived + * allocations. + */ +unsigned long transparent_hugepage_flags __read_mostly = +#ifdef CONFIG_TRANSPARENT_HUGEPAGE_ALWAYS + (1<<TRANSPARENT_HUGEPAGE_FLAG)| +#endif +#ifdef CONFIG_TRANSPARENT_HUGEPAGE_MADVISE + (1<<TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG)| +#endif + (1<<TRANSPARENT_HUGEPAGE_DEFRAG_FLAG)| + (1<<TRANSPARENT_HUGEPAGE_DEFRAG_KHUGEPAGED_FLAG); + +/* default scan 8*512 pte (or vmas) every 30 second */ +static unsigned int khugepaged_pages_to_scan __read_mostly = HPAGE_PMD_NR*8; +static unsigned int khugepaged_pages_collapsed; +static unsigned int khugepaged_full_scans; +static unsigned int khugepaged_scan_sleep_millisecs __read_mostly = 10000; +/* during fragmentation poll the hugepage allocator once every minute */ +static unsigned int khugepaged_alloc_sleep_millisecs __read_mostly = 60000; +static struct task_struct *khugepaged_thread __read_mostly; +static DEFINE_MUTEX(khugepaged_mutex); +static DEFINE_SPINLOCK(khugepaged_mm_lock); +static DECLARE_WAIT_QUEUE_HEAD(khugepaged_wait); +/* + * default collapse hugepages if there is at least one pte mapped like + * it would have happened if the vma was large enough during page + * fault. + */ +static unsigned int khugepaged_max_ptes_none __read_mostly = HPAGE_PMD_NR-1; + +static int khugepaged(void *none); +static int mm_slots_hash_init(void); +static int khugepaged_slab_init(void); +static void khugepaged_slab_free(void); + +#define MM_SLOTS_HASH_HEADS 1024 +static struct hlist_head *mm_slots_hash __read_mostly; +static struct kmem_cache *mm_slot_cache __read_mostly; + +/** + * struct mm_slot - hash lookup from mm to mm_slot + * @hash: hash collision list + * @mm_node: khugepaged scan list headed in khugepaged_scan.mm_head + * @mm: the mm that this information is valid for + */ +struct mm_slot { + struct hlist_node hash; + struct list_head mm_node; + struct mm_struct *mm; +}; + +/** + * struct khugepaged_scan - cursor for scanning + * @mm_head: the head of the mm list to scan + * @mm_slot: the current mm_slot we are scanning + * @address: the next address inside that to be scanned + * + * There is only the one khugepaged_scan instance of this cursor structure. + */ +struct khugepaged_scan { + struct list_head mm_head; + struct mm_slot *mm_slot; + unsigned long address; +} khugepaged_scan = { + .mm_head = LIST_HEAD_INIT(khugepaged_scan.mm_head), +}; + + +static int set_recommended_min_free_kbytes(void) +{ + struct zone *zone; + int nr_zones = 0; + unsigned long recommended_min; + extern int min_free_kbytes; + + if (!test_bit(TRANSPARENT_HUGEPAGE_FLAG, + &transparent_hugepage_flags) && + !test_bit(TRANSPARENT_HUGEPAGE_REQ_MADV_FLAG, + &transparent_hugepage_flags)) + return 0; + + for_each_populated_zone(zone) + nr_zones++; + + /* Make sure at least 2 hugepages are free for MIGRATE_RESERVE */ + recommended_min = pageblock_nr_pages * nr_zones * 2; + |