aboutsummaryrefslogtreecommitdiff
path: root/mm
diff options
context:
space:
mode:
authorJens Axboe <jaxboe@fusionio.com>2010-06-01 12:42:12 +0200
committerJens Axboe <jaxboe@fusionio.com>2010-06-01 12:42:12 +0200
commitb4ca761577535b2b4d153689ee97342797dfff05 (patch)
tree29054d55508f1faa22ec32acf7c245751af03348 /mm
parent28f4197e5d4707311febeec8a0eb97cb5fd93c97 (diff)
parent67a3e12b05e055c0415c556a315a3d3eb637e29e (diff)
downloadlinux-2.6.34-ux500-b4ca761577535b2b4d153689ee97342797dfff05.tar.gz
Merge branch 'master' into for-linus
Conflicts: fs/pipe.c Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
Diffstat (limited to 'mm')
-rw-r--r--mm/Kconfig17
-rw-r--r--mm/Makefile1
-rw-r--r--mm/compaction.c605
-rw-r--r--mm/filemap.c57
-rw-r--r--mm/highmem.c2
-rw-r--r--mm/hugetlb.c12
-rw-r--r--mm/ksm.c4
-rw-r--r--mm/memcontrol.c689
-rw-r--r--mm/memory.c13
-rw-r--r--mm/memory_hotplug.c36
-rw-r--r--mm/mempolicy.c227
-rw-r--r--mm/migrate.c74
-rw-r--r--mm/mincore.c263
-rw-r--r--mm/nommu.c32
-rw-r--r--mm/oom_kill.c5
-rw-r--r--mm/page_alloc.c317
-rw-r--r--mm/readahead.c2
-rw-r--r--mm/rmap.c40
-rw-r--r--mm/shmem.c111
-rw-r--r--mm/slab.c249
-rw-r--r--mm/slob.c8
-rw-r--r--mm/slub.c85
-rw-r--r--mm/sparse.c9
-rw-r--r--mm/swap.c1
-rw-r--r--mm/truncate.c10
-rw-r--r--mm/vmscan.c213
-rw-r--r--mm/vmstat.c253
27 files changed, 2574 insertions, 761 deletions
diff --git a/mm/Kconfig b/mm/Kconfig
index 9c61158308d..527136b2238 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -172,6 +172,15 @@ config SPLIT_PTLOCK_CPUS
default "4"
#
+# support for memory compaction
+config COMPACTION
+ bool "Allow for memory compaction"
+ select MIGRATION
+ depends on EXPERIMENTAL && HUGETLB_PAGE && MMU
+ help
+ Allows the compaction of memory for the allocation of huge pages.
+
+#
# support for page migration
#
config MIGRATION
@@ -180,9 +189,11 @@ config MIGRATION
depends on NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE
help
Allows the migration of the physical location of pages of processes
- while the virtual addresses are not changed. This is useful for
- example on NUMA systems to put pages nearer to the processors accessing
- the page.
+ while the virtual addresses are not changed. This is useful in
+ two situations. The first is on NUMA systems to put pages nearer
+ to the processors accessing. The second is when allocating huge
+ pages as migration can relocate pages to satisfy a huge page
+ allocation instead of reclaiming.
config PHYS_ADDR_T_64BIT
def_bool 64BIT || ARCH_PHYS_ADDR_T_64BIT
diff --git a/mm/Makefile b/mm/Makefile
index 6c2a73a54a4..8982504bd03 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -23,6 +23,7 @@ obj-$(CONFIG_NUMA) += mempolicy.o
obj-$(CONFIG_SPARSEMEM) += sparse.o
obj-$(CONFIG_SPARSEMEM_VMEMMAP) += sparse-vmemmap.o
obj-$(CONFIG_SLOB) += slob.o
+obj-$(CONFIG_COMPACTION) += compaction.o
obj-$(CONFIG_MMU_NOTIFIER) += mmu_notifier.o
obj-$(CONFIG_KSM) += ksm.o
obj-$(CONFIG_PAGE_POISONING) += debug-pagealloc.o
diff --git a/mm/compaction.c b/mm/compaction.c
new file mode 100644
index 00000000000..94cce51b0b3
--- /dev/null
+++ b/mm/compaction.c
@@ -0,0 +1,605 @@
+/*
+ * linux/mm/compaction.c
+ *
+ * Memory compaction for the reduction of external fragmentation. Note that
+ * this heavily depends upon page migration to do all the real heavy
+ * lifting
+ *
+ * Copyright IBM Corp. 2007-2010 Mel Gorman <mel@csn.ul.ie>
+ */
+#include <linux/swap.h>
+#include <linux/migrate.h>
+#include <linux/compaction.h>
+#include <linux/mm_inline.h>
+#include <linux/backing-dev.h>
+#include <linux/sysctl.h>
+#include <linux/sysfs.h>
+#include "internal.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
+ * at the end of a zone and migrate_pfn begins at the start. Movable pages
+ * are moved to the end of a zone during a compaction run and the run
+ * completes when free_pfn <= migrate_pfn
+ */
+struct compact_control {
+ struct list_head freepages; /* List of free pages to migrate to */
+ struct list_head migratepages; /* List of pages being migrated */
+ unsigned long nr_freepages; /* Number of isolated free pages */
+ 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 */
+
+ /* Account for isolated anon and file pages */
+ unsigned long nr_anon;
+ unsigned long nr_file;
+
+ unsigned int order; /* order a direct compactor needs */
+ int migratetype; /* MOVABLE, RECLAIMABLE etc */
+ struct zone *zone;
+};
+
+static unsigned long release_freepages(struct list_head *freelist)
+{
+ struct page *page, *next;
+ unsigned long count = 0;
+
+ list_for_each_entry_safe(page, next, freelist, lru) {
+ list_del(&page->lru);
+ __free_page(page);
+ count++;
+ }
+
+ return count;
+}
+
+/* Isolate free pages onto a private freelist. Must hold zone->lock */
+static unsigned long isolate_freepages_block(struct zone *zone,
+ unsigned long blockpfn,
+ struct list_head *freelist)
+{
+ unsigned long zone_end_pfn, end_pfn;
+ int total_isolated = 0;
+ struct page *cursor;
+
+ /* Get the last PFN we should scan for free pages at */
+ zone_end_pfn = zone->zone_start_pfn + zone->spanned_pages;
+ end_pfn = min(blockpfn + pageblock_nr_pages, zone_end_pfn);
+
+ /* Find the first usable PFN in the block to initialse page cursor */
+ for (; blockpfn < end_pfn; blockpfn++) {
+ if (pfn_valid_within(blockpfn))
+ break;
+ }
+ cursor = pfn_to_page(blockpfn);
+
+ /* Isolate free pages. This assumes the block is valid */
+ for (; blockpfn < end_pfn; blockpfn++, cursor++) {
+ int isolated, i;
+ struct page *page = cursor;
+
+ if (!pfn_valid_within(blockpfn))
+ continue;
+
+ if (!PageBuddy(page))
+ continue;
+
+ /* Found a free page, break it into order-0 pages */
+ isolated = split_free_page(page);
+ total_isolated += isolated;
+ for (i = 0; i < isolated; i++) {
+ list_add(&page->lru, freelist);
+ page++;
+ }
+
+ /* If a page was split, advance to the end of it */
+ if (isolated) {
+ blockpfn += isolated - 1;
+ cursor += isolated - 1;
+ }
+ }
+
+ return total_isolated;
+}
+
+/* Returns true if the page is within a block suitable for migration to */
+static bool suitable_migration_target(struct page *page)
+{
+
+ int migratetype = get_pageblock_migratetype(page);
+
+ /* Don't interfere with memory hot-remove or the min_free_kbytes blocks */
+ if (migratetype == MIGRATE_ISOLATE || migratetype == MIGRATE_RESERVE)
+ return false;
+
+ /* If the page is a large free page, then allow migration */
+ if (PageBuddy(page) && page_order(page) >= pageblock_order)
+ return true;
+
+ /* If the block is MIGRATE_MOVABLE, allow migration */
+ if (migratetype == MIGRATE_MOVABLE)
+ return true;
+
+ /* Otherwise skip the block */
+ return false;
+}
+
+/*
+ * Based on information in the current compact_control, find blocks
+ * suitable for isolating free pages from and then isolate them.
+ */
+static void isolate_freepages(struct zone *zone,
+ struct compact_control *cc)
+{
+ struct page *page;
+ unsigned long high_pfn, low_pfn, pfn;
+ unsigned long flags;
+ int nr_freepages = cc->nr_freepages;
+ struct list_head *freelist = &cc->freepages;
+
+ pfn = cc->free_pfn;
+ low_pfn = cc->migrate_pfn + pageblock_nr_pages;
+ high_pfn = low_pfn;
+
+ /*
+ * Isolate free pages until enough are available to migrate the
+ * pages on cc->migratepages. We stop searching if the migrate
+ * and free page scanners meet or enough free pages are isolated.
+ */
+ spin_lock_irqsave(&zone->lock, flags);
+ for (; pfn > low_pfn && cc->nr_migratepages > nr_freepages;
+ pfn -= pageblock_nr_pages) {
+ unsigned long isolated;
+
+ if (!pfn_valid(pfn))
+ continue;
+
+ /*
+ * Check for overlapping nodes/zones. It's possible on some
+ * configurations to have a setup like
+ * node0 node1 node0
+ * i.e. it's possible that all pages within a zones range of
+ * pages do not belong to a single zone.
+ */
+ page = pfn_to_page(pfn);
+ if (page_zone(page) != zone)
+ continue;
+
+ /* Check the block is suitable for migration */
+ if (!suitable_migration_target(page))
+ continue;
+
+ /* Found a block suitable for isolating free pages from */
+ isolated = isolate_freepages_block(zone, pfn, freelist);
+ nr_freepages += isolated;
+
+ /*
+ * Record the highest PFN we isolated pages from. When next
+ * looking for free pages, the search will restart here as
+ * page migration may have returned some pages to the allocator
+ */
+ if (isolated)
+ high_pfn = max(high_pfn, pfn);
+ }
+ spin_unlock_irqrestore(&zone->lock, flags);
+
+ /* split_free_page does not map the pages */
+ list_for_each_entry(page, freelist, lru) {
+ arch_alloc_page(page, 0);
+ kernel_map_pages(page, 1, 1);
+ }
+
+ cc->free_pfn = high_pfn;
+ cc->nr_freepages = nr_freepages;
+}
+
+/* Update the number of anon and file isolated pages in the zone */
+static void acct_isolated(struct zone *zone, struct compact_control *cc)
+{
+ struct page *page;
+ unsigned int count[NR_LRU_LISTS] = { 0, };
+
+ list_for_each_entry(page, &cc->migratepages, lru) {
+ int lru = page_lru_base_type(page);
+ count[lru]++;
+ }
+
+ cc->nr_anon = count[LRU_ACTIVE_ANON] + count[LRU_INACTIVE_ANON];
+ cc->nr_file = count[LRU_ACTIVE_FILE] + count[LRU_INACTIVE_FILE];
+ __mod_zone_page_state(zone, NR_ISOLATED_ANON, cc->nr_anon);
+ __mod_zone_page_state(zone, NR_ISOLATED_FILE, cc->nr_file);
+}
+
+/* Similar to reclaim, but different enough that they don't share logic */
+static bool too_many_isolated(struct zone *zone)
+{
+
+ unsigned long inactive, isolated;
+
+ inactive = zone_page_state(zone, NR_INACTIVE_FILE) +
+ zone_page_state(zone, NR_INACTIVE_ANON);
+ isolated = zone_page_state(zone, NR_ISOLATED_FILE) +
+ zone_page_state(zone, NR_ISOLATED_ANON);
+
+ return isolated > inactive;
+}
+
+/*
+ * Isolate all pages that can be migrated from the block pointed to by
+ * the migrate scanner within compact_control.
+ */
+static unsigned long isolate_migratepages(struct zone *zone,
+ struct compact_control *cc)
+{
+ unsigned long low_pfn, end_pfn;
+ struct list_head *migratelist = &cc->migratepages;
+
+ /* Do not scan outside zone boundaries */
+ low_pfn = max(cc->migrate_pfn, zone->zone_start_pfn);
+
+ /* Only scan within a pageblock boundary */
+ end_pfn = ALIGN(low_pfn + pageblock_nr_pages, pageblock_nr_pages);
+
+ /* Do not cross the free scanner or scan within a memory hole */
+ if (end_pfn > cc->free_pfn || !pfn_valid(low_pfn)) {
+ cc->migrate_pfn = end_pfn;
+ return 0;
+ }
+
+ /*
+ * Ensure that there are not too many pages isolated from the LRU
+ * list by either parallel reclaimers or compaction. If there are,
+ * delay for some time until fewer pages are isolated
+ */
+ while (unlikely(too_many_isolated(zone))) {
+ congestion_wait(BLK_RW_ASYNC, HZ/10);
+
+ if (fatal_signal_pending(current))
+ return 0;
+ }
+
+ /* Time to isolate some pages for migration */
+ spin_lock_irq(&zone->lru_lock);
+ for (; low_pfn < end_pfn; low_pfn++) {
+ struct page *page;
+ if (!pfn_valid_within(low_pfn))
+ continue;
+
+ /* Get the page and skip if free */
+ page = pfn_to_page(low_pfn);
+ if (PageBuddy(page))
+ continue;
+
+ /* Try isolate the page */
+ if (__isolate_lru_page(page, ISOLATE_BOTH, 0) != 0)
+ continue;
+
+ /* 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++;
+
+ /* Avoid isolating too much */
+ if (cc->nr_migratepages == COMPACT_CLUSTER_MAX)
+ break;
+ }
+
+ acct_isolated(zone, cc);
+
+ spin_unlock_irq(&zone->lru_lock);
+ cc->migrate_pfn = low_pfn;
+
+ return cc->nr_migratepages;
+}
+
+/*
+ * This is a migrate-callback that "allocates" freepages by taking pages
+ * from the isolated freelists in the block we are migrating to.
+ */
+static struct page *compaction_alloc(struct page *migratepage,
+ unsigned long data,
+ int **result)
+{
+ struct compact_control *cc = (struct compact_control *)data;
+ struct page *freepage;
+
+ /* Isolate free pages if necessary */
+ if (list_empty(&cc->freepages)) {
+ isolate_freepages(cc->zone, cc);
+
+ if (list_empty(&cc->freepages))
+ return NULL;
+ }
+
+ freepage = list_entry(cc->freepages.next, struct page, lru);
+ list_del(&freepage->lru);
+ cc->nr_freepages--;
+
+ return freepage;
+}
+
+/*
+ * We cannot control nr_migratepages and nr_freepages fully when migration is
+ * running as migrate_pages() has no knowledge of compact_control. When
+ * migration is complete, we count the number of pages on the lists by hand.
+ */
+static void update_nr_listpages(struct compact_control *cc)
+{
+ int nr_migratepages = 0;
+ int nr_freepages = 0;
+ struct page *page;
+
+ list_for_each_entry(page, &cc->migratepages, lru)
+ nr_migratepages++;
+ list_for_each_entry(page, &cc->freepages, lru)
+ nr_freepages++;
+
+ cc->nr_migratepages = nr_migratepages;
+ cc->nr_freepages = nr_freepages;
+}
+
+static int compact_finished(struct zone *zone,
+ struct compact_control *cc)
+{
+ unsigned int order;
+ unsigned long watermark = low_wmark_pages(zone) + (1 << cc->order);
+
+ if (fatal_signal_pending(current))
+ return COMPACT_PARTIAL;
+
+ /* Compaction run completes if the migrate and free scanner meet */
+ if (cc->free_pfn <= cc->migrate_pfn)
+ return COMPACT_COMPLETE;
+
+ /* Compaction run is not finished if the watermark is not met */
+ if (!zone_watermark_ok(zone, cc->order, watermark, 0, 0))
+ return COMPACT_CONTINUE;
+
+ if (cc->order == -1)
+ 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 */
+ if (!list_empty(&zone->free_area[order].free_list[cc->migratetype]))
+ return COMPACT_PARTIAL;
+
+ /* Job done if allocation would set block type */
+ if (order >= pageblock_order && zone->free_area[order].nr_free)
+ return COMPACT_PARTIAL;
+ }
+
+ return COMPACT_CONTINUE;
+}
+
+static int compact_zone(struct zone *zone, struct compact_control *cc)
+{
+ int ret;
+
+ /* 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;
+ cc->free_pfn &= ~(pageblock_nr_pages-1);
+
+ migrate_prep_local();
+
+ while ((ret = compact_finished(zone, cc)) == COMPACT_CONTINUE) {
+ unsigned long nr_migrate, nr_remaining;
+
+ if (!isolate_migratepages(zone, cc))
+ continue;
+
+ nr_migrate = cc->nr_migratepages;
+ migrate_pages(&cc->migratepages, compaction_alloc,
+ (unsigned long)cc, 0);
+ update_nr_listpages(cc);
+ nr_remaining = cc->nr_migratepages;
+
+ count_vm_event(COMPACTBLOCKS);
+ count_vm_events(COMPACTPAGES, nr_migrate - nr_remaining);
+ if (nr_remaining)
+ count_vm_events(COMPACTPAGEFAILED, nr_remaining);
+
+ /* Release LRU pages not migrated */
+ if (!list_empty(&cc->migratepages)) {
+ putback_lru_pages(&cc->migratepages);
+ cc->nr_migratepages = 0;
+ }
+
+ }
+
+ /* Release free pages and check accounting */
+ cc->nr_freepages -= release_freepages(&cc->freepages);
+ VM_BUG_ON(cc->nr_freepages != 0);
+
+ return ret;
+}
+
+static unsigned long compact_zone_order(struct zone *zone,
+ int order, gfp_t gfp_mask)
+{
+ struct compact_control cc = {
+ .nr_freepages = 0,
+ .nr_migratepages = 0,
+ .order = order,
+ .migratetype = allocflags_to_migratetype(gfp_mask),
+ .zone = zone,
+ };
+ INIT_LIST_HEAD(&cc.freepages);
+ INIT_LIST_HEAD(&cc.migratepages);
+
+ return compact_zone(zone, &cc);
+}
+
+int sysctl_extfrag_threshold = 500;
+
+/**
+ * try_to_compact_pages - Direct compact to satisfy a high-order allocation
+ * @zonelist: The zonelist used for the current allocation
+ * @order: The order of the current allocation
+ * @gfp_mask: The GFP mask of the current allocation
+ * @nodemask: The allowed nodes to allocate from
+ *
+ * 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)
+{
+ 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;
+
+ /*
+ * Check whether it is worth even starting compaction. The order check is
+ * 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)
+ return rc;
+
+ count_vm_event(COMPACTSTALL);
+
+ /* 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);
+ rc = max(status, rc);
+
+ if (zone_watermark_ok(zone, order, watermark, 0, 0))
+ break;
+ }
+
+ return rc;
+}
+
+
+/* Compact all zones within a node */
+static int compact_node(int nid)
+{
+ int zoneid;
+ pg_data_t *pgdat;
+ struct zone *zone;
+
+ if (nid < 0 || nid >= nr_node_ids || !node_online(nid))
+ return -EINVAL;
+ pgdat = NODE_DATA(nid);
+
+ /* Flush pending updates to the LRU lists */
+ lru_add_drain_all();
+
+ for (zoneid = 0; zoneid < MAX_NR_ZONES; zoneid++) {
+ struct compact_control cc = {
+ .nr_freepages = 0,
+ .nr_migratepages = 0,
+ .order = -1,
+ };
+
+ zone = &pgdat->node_zones[zoneid];
+ if (!populated_zone(zone))
+ continue;
+
+ cc.zone = zone;
+ INIT_LIST_HEAD(&cc.freepages);
+ INIT_LIST_HEAD(&cc.migratepages);
+
+ compact_zone(zone, &cc);
+
+ VM_BUG_ON(!list_empty(&cc.freepages));
+ VM_BUG_ON(!list_empty(&cc.migratepages));
+ }
+
+ return 0;
+}
+
+/* Compact all nodes in the system */
+static int compact_nodes(void)
+{
+ int nid;
+
+ for_each_online_node(nid)
+ compact_node(nid);
+
+ return COMPACT_COMPLETE;
+}
+
+/* The written value is actually unused, all memory is compacted */
+int sysctl_compact_memory;
+
+/* This is the entry point for compacting all nodes via /proc/sys/vm */
+int sysctl_compaction_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *length, loff_t *ppos)
+{
+ if (write)
+ return compact_nodes();
+
+ return 0;
+}
+
+int sysctl_extfrag_handler(struct ctl_table *table, int write,
+ void __user *buffer, size_t *length, loff_t *ppos)
+{
+ proc_dointvec_minmax(table, write, buffer, length, ppos);
+
+ return 0;
+}
+
+#if defined(CONFIG_SYSFS) && defined(CONFIG_NUMA)
+ssize_t sysfs_compact_node(struct sys_device *dev,
+ struct sysdev_attribute *attr,
+ const char *buf, size_t count)
+{
+ compact_node(dev->id);
+
+ return count;
+}
+static SYSDEV_ATTR(compact, S_IWUSR, NULL, sysfs_compact_node);
+
+int compaction_register_node(struct node *node)
+{
+ return sysdev_create_file(&node->sysdev, &attr_compact);
+}
+
+void compaction_unregister_node(struct node *node)
+{
+ return sysdev_remove_file(&node->sysdev, &attr_compact);
+}
+#endif /* CONFIG_SYSFS && CONFIG_NUMA */
diff --git a/mm/filemap.c b/mm/filemap.c
index 140ebda9640..20e5642e9f9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -151,6 +151,7 @@ void remove_from_page_cache(struct page *page)
spin_unlock_irq(&mapping->tree_lock);
mem_cgroup_uncharge_cache_page(page);
}
+EXPORT_SYMBOL(remove_from_page_cache);
static int sync_page(void *word)
{
@@ -441,7 +442,7 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
/*
* Splice_read and readahead add shmem/tmpfs pages into the page cache
* before shmem_readpage has a chance to mark them as SwapBacked: they
- * need to go on the active_anon lru below, and mem_cgroup_cache_charge
+ * need to go on the anon lru below, and mem_cgroup_cache_charge
* (called in add_to_page_cache) needs to know where they're going too.
*/
if (mapping_cap_swap_backed(mapping))
@@ -452,7 +453,7 @@ int add_to_page_cache_lru(struct page *page, struct address_space *mapping,
if (page_is_file_cache(page))
lru_cache_add_file(page);
else
- lru_cache_add_active_anon(page);
+ lru_cache_add_anon(page);
}
return ret;
}
@@ -461,9 +462,15 @@ EXPORT_SYMBOL_GPL(add_to_page_cache_lru);
#ifdef CONFIG_NUMA
struct page *__page_cache_alloc(gfp_t gfp)
{
+ int n;
+ struct page *page;
+
if (cpuset_do_page_mem_spread()) {
- int n = cpuset_mem_spread_node();
- return alloc_pages_exact_node(n, gfp, 0);
+ get_mems_allowed();
+ n = cpuset_mem_spread_node();
+ page = alloc_pages_exact_node(n, gfp, 0);
+ put_mems_allowed();
+ return page;
}
return alloc_pages(gfp, 0);
}
@@ -1099,6 +1106,12 @@ page_not_up_to_date_locked:
}
readpage:
+ /*
+ * A previous I/O error may have been due to temporary
+ * failures, eg. multipath errors.
+ * PG_error will be set again if readpage fails.
+ */
+ ClearPageError(page);
/* Start the actual read. The read will unlock the page. */
error = mapping->a_ops->readpage(filp, page);
@@ -1263,7 +1276,7 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
{
struct file *filp = iocb->ki_filp;
ssize_t retval;
- unsigned long seg;
+ unsigned long seg = 0;
size_t count;
loff_t *ppos = &iocb->ki_pos;
@@ -1290,21 +1303,47 @@ generic_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
retval = mapping->a_ops->direct_IO(READ, iocb,
iov, pos, nr_segs);
}
- if (retval > 0)
+ if (retval > 0) {
*ppos = pos + retval;
- if (retval) {
+ count -= retval;
+ }
+
+ /*
+ * Btrfs can have a short DIO read if we encounter
+ * compressed extents, so if there was an error, or if
+ * we've already read everything we wanted to, or if
+ * there was a short read because we hit EOF, go ahead
+ * and return. Otherwise fallthrough to buffered io for
+ * the rest of the read.
+ */
+ if (retval < 0 || !count || *ppos >= size) {
file_accessed(filp);
goto out;
}
}
}
+ count = retval;
for (seg = 0; seg < nr_segs; seg++) {
read_descriptor_t desc;
+ loff_t offset = 0;
+
+ /*
+ * If we did a short DIO read we need to skip the section of the
+ * iov that we've already read data into.
+ */
+ if (count) {
+ if (count > iov[seg].iov_len) {
+ count -= iov[seg].iov_len;
+ continue;
+ }
+ offset = count;
+ count = 0;
+ }
desc.written = 0;
- desc.arg.buf = iov[seg].iov_base;
- desc.count = iov[seg].iov_len;
+ desc.arg.buf = iov[seg].iov_base + offset;
+ desc.count = iov[seg].iov_len - offset;
if (desc.count == 0)
continue;
desc.error = 0;
diff --git a/mm/highmem.c b/mm/highmem.c
index bed8a8bfd01..66baa20f78f 100644
--- a/mm/highmem.c
+++ b/mm/highmem.c
@@ -422,7 +422,7 @@ void __init page_address_init(void)
#endif /* defined(CONFIG_HIGHMEM) && !defined(WANT_PAGE_VIRTUAL) */
-#if defined(CONFIG_DEBUG_HIGHMEM) && defined(CONFIG_TRACE_IRQFLAGS_SUPPORT)
+#ifdef CONFIG_DEBUG_HIGHMEM
void debug_kmap_atomic(enum km_type type)
{
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 4c9e6bbf377..54d42b009db 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -465,11 +465,13 @@ static struct page *dequeue_huge_page_vma(struct hstate *h,
struct page *page = NULL;
struct mempolicy *mpol;
nodemask_t *nodemask;
- struct zonelist *zonelist = huge_zonelist(vma, address,
- htlb_alloc_mask, &mpol, &nodemask);
+ struct zonelist *zonelist;
struct zone *zone;
struct zoneref *z;
+ get_mems_allowed();
+ zonelist = huge_zonelist(vma, address,
+ htlb_alloc_mask, &mpol, &nodemask);
/*
* A child process with MAP_PRIVATE mappings created by their parent
* have no page reserves. This check ensures that reservations are
@@ -477,11 +479,11 @@ static struct page *dequeue_huge_page_vma(struct hstate *h,
*/
if (!vma_has_reserves(vma) &&
h->free_huge_pages - h->resv_huge_pages == 0)
- return NULL;
+ goto err;
/* If reserves cannot be used, ensure enough pages are in the pool */
if (avoid_reserve && h->free_huge_pages - h->resv_huge_pages == 0)
- return NULL;
+ goto err;;
for_each_zone_zonelist_nodemask(zone, z, zonelist,
MAX_NR_ZONES - 1, nodemask) {
@@ -500,7 +502,9 @@ static struct page *dequeue_huge_page_vma(struct hstate *h,
break;
}
}
+err:
mpol_cond_put(mpol);
+ put_mems_allowed();
return page;
}
diff --git a/mm/ksm.c b/mm/ksm.c
index 956880f2ff4..6c3e99b4ae7 100644
--- a/mm/ksm.c
+++ b/mm/ksm.c
@@ -318,14 +318,14 @@ static void hold_anon_vma(struct rmap_item *rmap_item,
struct anon_vma *anon_vma)
{
rmap_item->anon_vma = anon_vma;
- atomic_inc(&anon_vma->ksm_refcount);
+ atomic_inc(&anon_vma->external_refcount);
}
static void drop_anon_vma(struct rmap_item *rmap_item)
{
struct anon_vma *anon_vma = rmap_item->anon_vma;
- if (atomic_dec_and_lock(&anon_vma->ksm_refcount, &anon_vma->lock)) {
+ if (atomic_dec_and_lock(&anon_vma->external_refcount, &anon_vma->lock)) {
int empty = list_empty(&anon_vma->head);
spin_unlock(&anon_vma->lock);
if (empty)
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index c8569bc298f..c6ece0a5759 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -149,16 +149,35 @@ struct mem_cgroup_threshold {
u64 threshold;
};
+/* For threshold */
struct mem_cgroup_threshold_ary {
/* An array index points to threshold just below usage. */
- atomic_t current_threshold;
+ int current_threshold;
/* Size of entries[] */
unsigned int size;
/* Array of thresholds */
struct mem_cgroup_threshold entries[0];
};
+struct mem_cgroup_thresholds {
+ /* Primary thresholds array */
+ struct mem_cgroup_threshold_ary *primary;
+ /*
+ * Spare threshold array.
+ * This is needed to make mem_cgroup_unregister_event() "never fail".
+ * It must be able to store at least primary->size - 1 entries.
+ */
+ struct mem_cgroup_threshold_ary *spare;
+};
+
+/* for OOM */
+struct mem_cgroup_eventfd_list {
+ struct list_head list;
+ struct eventfd_ctx *eventfd;
+};
+
static void mem_cgroup_threshold(struct mem_cgroup *mem);
+static void mem_cgroup_oom_notify(struct mem_cgroup *mem);
/*
* The memory controller data structure. The memory controller controls both
@@ -207,6 +226,8 @@ struct mem_cgroup {
atomic_t refcnt;
unsigned int swappiness;
+ /* OOM-Killer disable */
+ int oom_kill_disable;
/* set when res.limit == memsw.limit */
bool memsw_is_minimum;
@@ -215,17 +236,19 @@ struct mem_cgroup {
struct mutex thresholds_lock;
/* thresholds for memory usage. RCU-protected */
- struct mem_cgroup_threshold_ary *thresholds;
+ struct mem_cgroup_thresholds thresholds;
/* thresholds for mem+swap usage. RCU-protected */
- struct mem_cgroup_threshold_ary *memsw_thresholds;
+ struct mem_cgroup_thresholds memsw_thresholds;
+
+ /* For oom notifier event fd */
+ struct list_head oom_notify;
/*
* Should we move charges of a task when a task is moved into this
* mem_cgroup ? And what type of charges should we move ?
*/
unsigned long move_charge_at_immigrate;
-
/*
* percpu counter.
*/
@@ -239,6 +262,7 @@ struct mem_cgroup {
*/
enum move_type {
MOVE_CHARGE_TYPE_ANON, /* private anonymous page and swap of it */
+ MOVE_CHARGE_TYPE_FILE, /* file page(including tmpfs) and swap of it */
NR_MOVE_TYPE,
};
@@ -255,6 +279,18 @@ static struct move_charge_struct {
.waitq = __WAIT_QUEUE_HEAD_INITIALIZER(mc.waitq),
};
+static bool move_anon(void)
+{
+ return test_bit(MOVE_CHARGE_TYPE_ANON,
+ &mc.to->move_charge_at_immigrate);
+}
+
+static bool move_file(void)
+{
+ return test_bit(MOVE_CHARGE_TYPE_FILE,
+ &mc.to->move_charge_at_immigrate);
+}
+
/*
* Maximum loops in mem_cgroup_hierarchical_reclaim(), used for soft
* limit reclaim to prevent infinite loops, if they ever occur.
@@ -282,9 +318,12 @@ enum charge_type {
/* for encoding cft->private value on file */
#define _MEM (0)
#define _MEMSWAP (1)
+#define _OOM_TYPE (2)
#define MEMFILE_PRIVATE(x, val) (((x) << 16) | (val))
#define MEMFILE_TYPE(val) (((val) >> 16) & 0xffff)
#define MEMFILE_ATTR(val) ((val) & 0xffff)
+/* Used for OOM nofiier */
+#define OOM_CONTROL (0)
/*
* Reclaim flags for mem_cgroup_hierarchical_reclaim
@@ -1293,14 +1332,62 @@ static void mem_cgroup_oom_unlock(struct mem_cgroup *mem)
static DEFINE_MUTEX(memcg_oom_mutex);
static DECLARE_WAIT_QUEUE_HEAD(memcg_oom_waitq);
+struct oom_wait_info {
+ struct mem_cgroup *mem;
+ wait_queue_t wait;
+};
+
+static int memcg_oom_wake_function(wait_queue_t *wait,
+ unsigned mode, int sync, void *arg)
+{
+ struct mem_cgroup *wake_mem = (struct mem_cgroup *)arg;
+ struct oom_wait_info *oom_wait_info;
+
+ oom_wait_info = container_of(wait, struct oom_wait_info, wait);
+
+ if (oom_wait_info->mem == wake_mem)
+ goto wakeup;
+ /* if no hierarchy, no match */
+ if (!oom_wait_info->mem->use_hierarchy || !wake_mem->use_hierarchy)
+ return 0;
+ /*
+ * Both of oom_wait_info->mem and wake_mem are stable under us.
+ * Then we can use css_is_ancestor without taking care of RCU.
+ */
+ if (!css_is_ancestor(&oom_wait_info->mem->css, &wake_mem->css) &&
+ !css_is_ancestor(&wake_mem->css, &oom_wait_info->mem->css))
+ return 0;
+
+wakeup:
+ return autoremove_wake_function(wait, mode, sync, arg);
+}
+
+static void memcg_wakeup_oom(struct mem_cgroup *mem)
+{
+ /* for filtering, pass "mem" as argument. */
+ __wake_up(&memcg_oom_waitq, TASK_NORMAL, 0, mem);
+}
+
+static void memcg_oom_recover(struct mem_cgroup *mem)
+{
+ if (mem->oom_kill_disable && atomic_read(&mem->oom_lock))
+ memcg_wakeup_oom(mem);
+}
+
/*
* try to call OOM killer. returns false if we should exit memory-reclaim loop.
*/
bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask)
{
- DEFINE_WAIT(wait);
- bool locked;
+ struct oom_wait_info owait;
+ bool locked, need_to_kill;
+ owait.mem = mem;
+ owait.wait.flags = 0;
+ owait.wait.func = memcg_oom_wake_function;
+ owait.wait.private = current;
+ INIT_LIST_HEAD(&owait.wait.task_list);
+ need_to_kill = true;
/* At first, try to OOM lock hierarchy under mem.*/
mutex_lock(&memcg_oom_mutex);
locked = mem_cgroup_oom_lock(mem);
@@ -1309,32 +1396,23 @@ bool mem_cgroup_handle_oom(struct mem_cgroup *mem, gfp_t mask)
* accounting. So, UNINTERRUPTIBLE is appropriate. But SIGKILL
* under OOM is always welcomed, use TASK_KILLABLE here.
*/
- if (!locked)
- prepare_to_wait(&memcg_oom_waitq, &wait, TASK_KILLABLE);
+ prepare_to_wait(&memcg_oom_waitq, &owait.wait, TASK_KILLABLE);
+ if (!locked || mem->oom_kill_disable)
+ need_to_kill = false;
+ if (locked)
+ mem_cgroup_oom_notify(mem);
mutex_unlock(&memcg_oom_mutex);
- if (locked)
+ if (need_to_kill) {
+ finish_wait(&memcg_oom_waitq, &owait.wait);
mem_cgroup_out_of_memory(mem, mask);
- else {
+ } else {
schedule();
- finish_wait(&memcg_oom_waitq, &wait);
+ finish_wait(&memcg_oom_waitq, &owait.wait);
}
mutex_lock(&memcg_oom_mutex);
mem_cgroup_oom_unlock(mem);
- /*
- * Here, we use global waitq .....more fine grained waitq ?
- * Assume following hierarchy.
- * A/
- * 01
- * 02
- * assume OOM happens both in A and 01 at the same time. Tthey are
- * mutually exclusive by lock. (kill in 01 helps A.)
- * When we use per memcg waitq, we have to wake up waiters on A and 02
- * in addtion to waiters on 01. We use global waitq for avoiding mess.
- * It will not be a big problem.
- * (And a task may be moved to other groups while it's waiting for OOM.)
- */
- wake_up_all(&memcg_oom_waitq);
+ memcg_wakeup_oom(mem);
mutex_unlock(&memcg_oom_mutex);
if (test_thread_flag(TIF_MEMDIE) || fatal_signal_pending(current))
@@ -2118,15 +2196,6 @@ __do_uncharge(struct mem_cgroup *mem, const enum charge_type ctype)
/* If swapout, usage of swap doesn't decrease */
if (!do_swap_account || ctype == MEM_CGROUP_CHARGE_TYPE_SWAPOUT)
uncharge_memsw = false;
- /*
- * do_batch > 0 when unmapping pages or inode invalidate/truncate.
- * In those cases, all pages freed continously can be expected to be in
- * the same cgroup and we have chance to coalesce uncharges.
- * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE)
- * because we want to do uncharge as soon as possible.
- */
- if (!current->memcg_batch.do_batch || test_thread_flag(TIF_MEMDIE))
- goto direct_uncharge;
batch = &current->memcg_batch;
/*
@@ -2137,6 +2206,17 @@ __do_uncharge(struct mem_cgroup *mem, const enum charge_type ctype)
if (!batch->memcg)
batch->memcg = mem;
/*
+ * do_batch > 0 when unmapping pages or inode invalidate/truncate.
+ * In those cases, all pages freed continously can be expected to be in
+ * the same cgroup and we have chance to coalesce uncharges.
+ * But we do uncharge one by one if this is killed by OOM(TIF_MEMDIE)
+ * because we want to do uncharge as soon as possible.
+ */
+
+ if (!batch->do_batch || test_thread_flag(TIF_MEMDIE))
+ goto direct_uncharge;
+
+ /*
* In typical case, batch->memcg == mem. This means we can
* merge a series of uncharges to an uncharge of res_counter.
* If not, we uncharge res_counter ony by one.
@@ -2152,6 +2232,8 @@ direct_uncharge:
res_counter_uncharge(&mem->res, PAGE_SIZE);
if (uncharge_memsw)
res_counter_uncharge(&mem->memsw, PAGE_SIZE);
+ if (unlikely(batch->memcg != mem))
+ memcg_oom_recover(mem);
return;
}
@@ -2188,7 +2270,8 @@ __mem_cgroup_uncharge_common(struct page *page, enum charge_type ctype)
switch (ctype) {
case MEM_CGROUP_CHARGE_TYPE_MAPPED:
case MEM_CGROUP_CHARGE_TYPE_DROP:
- if (page_mapped(page))
+ /* See mem_cgroup_prepare_migration() */
+ if (page_mapped(page) || PageCgroupMigration(pc))
goto unlock_out;
break;
case MEM_CGROUP_CHARGE_TYPE_SWAPOUT:
@@ -2288,6 +2371,7 @@ void mem_cgroup_uncharge_end(void)
res_counter_uncharge(&batch->memcg->res, batch->bytes);
if (batch->memsw_bytes)
res_counter_uncharge(&batch->memcg->memsw, batch->memsw_bytes);
+ memcg_oom_recover(batch->memcg);
/* forget this pointer (for sanity check) */
batch->memcg = NULL;
}
@@ -2410,10 +2494,12 @@ static inline int mem_cgroup_move_swap_account(swp_entry_t entry,
* Before starting migration, account PAGE_SIZE to mem_cgroup that the old
* page belongs to.
*/
-int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
+int mem_cgroup_prepare_migration(struct page *page,
+ struct page *newpage, struct mem_cgroup **ptr)
{
struct page_cgroup *pc;
struct mem_cgroup *mem = NULL;
+ enum charge_type ctype;
int ret = 0;
if (mem_cgroup_disabled())
@@ -2424,69 +2510,125 @@ int mem_cgroup_prepare_migration(struct page *page, struct mem_cgroup **ptr)
if (PageCgroupUsed(pc)) {
mem = pc->mem_cgroup;
css_get(&mem->css);
+ /*
+ * At migrating an anonymous page, its mapcount goes down
+ * to 0 and uncharge() will be called. But, even if it's fully
+ * unmapped, migration may fail and this page has to be
+ * charged again. We set MIGRATION flag here and delay uncharge
+ * until end_migration() is called
+ *
+ * Corner Case Thinking
+ * A)
+ * When the old page was mapped as Anon and it's unmap-and-freed
+ * while migration was ongoing.
+ * If unmap finds the old page, uncharge() of it will be delayed
+ * until end_migration(). If unmap finds a new page, it's
+ * uncharged when it make mapcount to be 1->0. If unmap code
+ * finds swap_migration_entry, the new page will not be mapped
+ * and end_migration() will find it(mapcount==0).
+ *
+ * B)
+ * When the old page was mapped but migraion fails, the kernel
+ * remaps it. A charge for it is kept by MIGRATION flag even
+ * if mapcount goes down to 0. We can do remap successfully
+ * without charging it again.
+ *
+ * C)
+ * The "old" page is under lock_page() until the end of
+ * migration, so, the old page itself will not be swapped-out.
+ * If the new page is swapped out before end_migraton, our
+ * hook to usual swap-out path will catch the event.
+ */
+ if (PageAnon(page))
+ SetPageCgroupMigration(pc);
}
unlock_page_cgroup(pc);
+ /*
+ * If the page is not charged at this point,
+ * we return here.
+ */
+ if (!mem)
+ return 0;
*ptr = mem;
- if (mem) {
- ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false);
- css_put(&mem->css);
+ ret = __mem_cgroup_try_charge(NULL, GFP_KERNEL, ptr, false);
+ css_put(&mem->css);/* drop extra refcnt */
+ if (ret || *ptr == NULL) {
+ if (PageAnon(page)) {
+ lock_page_cgroup(pc);
+ ClearPageCgroupMigration(pc);
+ unlock_page_cgroup(pc);
+ /*
+ * The old page may be fully unmapped while we kept it.
+ */
+ mem_cgroup_uncharge_page(page);
+ }
+ return -ENOMEM;
}
+ /*
+ * We charge new page before it's used/mapped. So, even if unlock_page()
+ * is called before end_migration, we can catch all events on this new
+ * page. In the case new page is migrated but not remapped, new page's
+ * mapcount will be finally 0 and we call uncharge in end_migration().
+ */
+ pc = lookup_page_cgroup(newpage);
+ if (PageAnon(page))
+ ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
+ else if (page_is_file_cache(page))
+ ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
+ else
+ ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
+ __mem_cgroup_commit_charge(mem, pc, ctype);
return ret;
}
/* remove redundant charge if migration failed*/
void mem_cgroup_end_migration(struct mem_cgroup *mem,
- struct page *oldpage, struct page *newpage)
+ struct page *oldpage, struct page *newpage)
{
- struct page *target, *unused;
+ struct page *used, *unused;
struct page_cgroup *pc;
- enum charge_type ctype;
if (!mem)
return;
+ /* blocks rmdir() */
cgroup_exclude_rmdir(&mem->css);
/* at migration success, oldpage->mapping is NULL. */
if (oldpage->mapping) {
- target = oldpage;
- unused = NULL;
+ used = oldpage;
+ unused = newpage;
} else {
- target = newpage;
+ used = newpage;
unused = oldpage;
}
-
- if (PageAnon(target))
- ctype = MEM_CGROUP_CHARGE_TYPE_MAPPED;
- else if (page_is_file_cache(target))
- ctype = MEM_CGROUP_CHARGE_TYPE_CACHE;
- else
- ctype = MEM_CGROUP_CHARGE_TYPE_SHMEM;
-
- /* unused page is not on radix-tree now. */
- if (unused)
- __mem_cgroup_uncharge_common(unused, ctype);
-
- pc = lookup_page_cgroup(target);
/*
- * __mem_cgroup_commit_charge() check PCG_USED bit of page_cgroup.
- * So, double-counting is effectively avoided.
+ * We disallowed uncharge of pages under migration because mapcount
+ * of the page goes down to zero, temporarly.
+ * Clear the flag and check the page should be charged.
*/
- __mem_cgroup_commit_charge(mem, pc, ctype);
+ pc = lookup_page_cgroup(oldpage);
+ lock_page_cgroup(pc);
+ ClearPageCgroupMigration(pc);
+ unlock_page_cgroup(pc);
+
+ if (unused != oldpage)
+ pc = lookup_page_cgroup(unused);
+ __mem_cgroup_uncharge_common(unused, MEM_CGROUP_CHARGE_TYPE_FORCE);
+ pc = lookup_page_cgroup(used);
/*
- * Both of oldpage and newpage are still under lock_page().
- * Then, we don't have to care about race in radix-tree.
- * But we have to be careful that this page is unmapped or not.
- *
- * There is a case for !page_mapped(). At the start of
- * migration, oldpage was mapped. But now, it's zapped.
- * But we know *target* page is not freed/reused under us.
- * mem_cgroup_uncharge_page() does all necessary checks.
+ * If a page is a file cache, radix-tree replacement is very atomic
+ * and we can skip this check. When it was an Anon page, its mapcount
+ * goes down to 0. But because we added MIGRATION flage, it's not
+ * uncharged yet. There are several case but page->mapcount check
+ * and USED bit check in mem_cgroup_uncharge_page() will do enough
+ * check. (see prepare_charge() also)
*/
- if (ctype == MEM_CGROUP_CHARGE_TYPE_MAPPED)
- mem_cgroup_uncharge_page(target);
+ if (PageAnon(used))
+ mem_cgroup_uncharge_page(used);
/*
- * At migration, we may charge account against cgroup which has no tasks
+ * At migration, we may charge account against cgroup which has no
+ * tasks.
* So, rmdir()->pre_destroy() can be called while we do this charge.
* In that case, we need to call pre_destroy() again. check it here.
*/
@@ -2524,10 +2666,11 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
unsigned long long val)
{
int retry_count;
- u64 memswlimit;
+ u64 memswlimit, memlimit;
int ret = 0;
int children = mem_cgroup_count_children(memcg);
u64 curusage, oldusage;
+ int enlarge;
/*
* For keeping hierarchical_reclaim simple, how long we should retry
@@ -2538,6 +2681,7 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
oldusage = res_counter_read_u64(&memcg->res, RES_USAGE);
+ enlarge = 0;
while (retry_count) {
if (signal_pending(current)) {
ret = -EINTR;
@@ -2555,6 +2699,11 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
mutex_unlock(&set_limit_mutex);
break;
}
+
+ memlimit = res_counter_read_u64(&memcg->res, RES_LIMIT);
+ if (memlimit < val)
+ enlarge = 1;
+
ret = res_counter_set_limit(&memcg->res, val);
if (!ret) {
if (memswlimit == val)
@@ -2576,6 +2725,8 @@ static int mem_cgroup_resize_limit(struct mem_cgroup *memcg,
else
oldusage = curusage;
}
+ if (!ret && enlarge)
+ memcg_oom_recover(memcg);
return ret;
}
@@ -2584,9 +2735,10 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
unsigned long long val)
{
int retry_count;
- u64 memlimit, oldusage, curusage;
+ u64 memlimit, memswlimit, oldusage, curusage;
int children = mem_cgroup_count_children(memcg);
int ret = -EBUSY;
+ int enlarge = 0;
/* see mem_cgroup_resize_res_limit */
retry_count = children * MEM_CGROUP_RECLAIM_RETRIES;
@@ -2608,6 +2760,9 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
mutex_unlock(&set_limit_mutex);
break;
}
+ memswlimit = res_counter_read_u64(&memcg->memsw, RES_LIMIT);
+ if (memswlimit < val)
+ enlarge = 1;
ret = res_counter_set_limit(&memcg->memsw, val);
if (!ret) {
if (memlimit == val)
@@ -2630,6 +2785,8 @@ static int mem_cgroup_resize_memsw_limit(struct mem_cgroup *memcg,
else
oldusage = curusage;
}
+ if (!ret && enlarge)
+ memcg_oom_recover(memcg);
return ret;
}
@@ -2821,6 +2978,7 @@ move_account:
if (ret)
break;
}
+ memcg_oom_recover(mem);
/* it seems parent cgroup doesn't have enough mem */
if (ret == -ENOMEM)
goto try_to_free;
@@ -3311,9 +3469,9 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
rcu_read_lock();
if (!swap)
- t = rcu_dereference(memcg->thresholds);
+ t = rcu_dereference(memcg->thresholds.primary);
else
- t = rcu_dereference(memcg->memsw_thresholds);
+ t = rcu_dereference(memcg->memsw_thresholds.primary);
if (!t)
goto unlock;
@@ -3325,7 +3483,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
* If it's not true, a threshold was crossed after last
* call of __mem_cgroup_threshold().
*/
- i = atomic_read(&t->current_threshold);
+ i = t->current_threshold;
/*
* Iterate backward over array of thresholds starting from
@@ -3349,7 +3507,7 @@ static void __mem_cgroup_threshold(struct mem_cgroup *memcg, bool swap)
eventfd_signal(t->entries[i].eventfd, 1);
/* Update current_threshold */
- atomic_set(&t->current_threshold, i - 1);
+ t->current_threshold = i - 1;
unlock:
rcu_read_unlock();
}
@@ -3369,106 +3527,117 @@ static int compare_thresholds(const void *a, const void *b)
return _a->threshold - _b->threshold;
}
-static int mem_cgroup_register_event(struct cgroup *cgrp, struct cftype *cft,
- struct eventfd_ctx *eventfd, const char *args)
+static int mem_cgroup_oom_notify_cb(struct mem_cgroup *mem, void *data)
+{
+ struct mem_cgroup_eventfd_list *ev;
+
+ list_for_each_entry(ev, &mem->oom_notify, list)
+ eventfd_signal(ev->eventfd, 1);
+ return 0;
+}
+
+static void mem_cgroup_oom_notify(struct mem_cgroup *mem)
+{
+ mem_cgroup_walk_tree(mem, NULL, mem_cgroup_oom_notify_cb);
+}
+
+static int mem_cgroup_usage_register_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
- struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
+ struct mem_cgroup_thresholds *thresholds;
+ struct mem_cgroup_threshold_ary *new;
int type = MEMFILE_TYPE(cft->private);
u64 threshold, usage;
- int size;
- int i, ret;
+ int i, size, ret;
ret = res_counter_memparse_write_strategy(args, &threshold);
if (ret)
return ret;
mutex_lock(&memcg->thresholds_lock);
+
if (type == _MEM)
- thresholds = memcg->thresholds;
+ thresholds = &memcg->thresholds;
else if (type == _MEMSWAP)
- thresholds = memcg->memsw_thresholds;
+ thresholds = &memcg->memsw_thresholds;
else
BUG();
usage = mem_cgroup_usage(memcg, type == _MEMSWAP);
/* Check if a threshold crossed before adding a new one */
- if (thresholds)
+ if (thresholds->primary)
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
- if (thresholds)
- size = thresholds->size + 1;
- else
- size = 1;
+ size = thresholds->primary ? thresholds->primary->size + 1 : 1;
/* Allocate memory for new array of thresholds */
- thresholds_new = kmalloc(sizeof(*thresholds_new) +
- size * sizeof(struct mem_cgroup_threshold),
+ new = kmalloc(sizeof(*new) + size * sizeof(struct mem_cgroup_threshold),
GFP_KERNEL);
- if (!thresholds_new) {
+ if (!new) {
ret = -ENOMEM;
goto unlock;
}
- thresholds_new->size = size;
+ new->size = size;
/* Copy thresholds (if any) to new array */
- if (thresholds)
- memcpy(thresholds_new->entries, thresholds->entries,
- thresholds->size *
+ if (thresholds->primary) {
+ memcpy(new->entries, thresholds->primary->entries, (size - 1) *
sizeof(struct mem_cgroup_threshold));
+ }
+
/* Add new threshold */
- thresholds_new->entries[size - 1].eventfd = eventfd;
- thresholds_new->entries[size - 1].threshold = threshold;
+ new->entries[size - 1].eventfd = eventfd;
+ new->entries[size - 1].threshold = threshold;
/* Sort thresholds. Registering of new threshold isn't time-critical */
- sort(thresholds_new->entries, size,
- sizeof(struct mem_cgroup_threshold),
+ sort(new->entries, size, sizeof(struct mem_cgroup_threshold),
compare_thresholds, NULL);
/* Find current threshold */
- atomic_set(&thresholds_new->current_threshold, -1);
+ new->current_threshold = -1;
for (i = 0; i < size; i++) {
- if (thresholds_new->entries[i].threshold < usage) {
+ if (new->entries[i].threshold < usage) {
/*
- * thresholds_new->current_threshold will not be used
- * until rcu_assign_pointer(), so it's safe to increment
+ * new->current_threshold will not be used until
+ * rcu_assign_pointer(), so it's safe to increment
* it here.
*/
- atomic_inc(&thresholds_new->current_threshold);
+ ++new->current_threshold;
}
}
- if (type == _MEM)
- rcu_assign_pointer(memcg->thresholds, thresholds_new);
- else
- rcu_assign_pointer(memcg->memsw_thresholds, thresholds_new);
+ /* Free old spare buffer and save old primary buffer as spare */
+ kfree(thresholds->spare);
+ thresholds->spare = thresholds->primary;
+
+ rcu_assign_pointer(thresholds->primary, new);
- /* To be sure that nobody uses thresholds before freeing it */
+ /* To be sure that nobody uses thresholds */
synchronize_rcu();
- kfree(thresholds);
unlock:
mutex_unlock(&memcg->thresholds_lock);
return ret;
}
-static int mem_cgroup_unregister_event(struct cgroup *cgrp, struct cftype *cft,
- struct eventfd_ctx *eventfd)
+static void mem_cgroup_usage_unregister_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd)
{
struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
- struct mem_cgroup_threshold_ary *thresholds, *thresholds_new;
+ struct mem_cgroup_thresholds *thresholds;
+ struct mem_cgroup_threshold_ary *new;
int type = MEMFILE_TYPE(cft->private);
u64 usage;
- int size = 0;
- int i, j, ret;
+ int i, j, size;
mutex_lock(&memcg->thresholds_lock);
if (type == _MEM)
- thresholds = memcg->thresholds;
+ thresholds = &memcg->thresholds;
else if (type == _MEMSWAP)
- thresholds = memcg->memsw_thresholds;
+ thresholds = &memcg->memsw_thresholds;
else
BUG();
@@ -3484,59 +3653,136 @@ static int mem_cgroup_unregister_event(struct cgroup *cgrp, struct cftype *cft,
__mem_cgroup_threshold(memcg, type == _MEMSWAP);
/* Calculate new number of threshold */
- for (i = 0; i < thresholds->size; i++) {
- if (thresholds->entries[i].eventfd != eventfd)
+ size = 0;
+ for (i = 0; i < thresholds->primary->size; i++) {
+ if (thresholds->primary->entries[i].eventfd != eventfd)
size++;
}
+ new = thresholds->spare;
+
/* Set thresholds array to NULL if we don't have thresholds */
if (!size) {
- thresholds_new = NULL;
- goto assign;
+ kfree(new);
+ new = NULL;
+ goto swap_buffers;
}
- /* Allocate memory for new array of thresholds */
- thresholds_new = kmalloc(sizeof(*thresholds_new) +
- size * sizeof(struct mem_cgroup_threshold),
- GFP_KERNEL);
- if (!thresholds_new) {
- ret = -ENOMEM;
- goto unlock;
- }
- thresholds_new->size = size;
+ new->size = size;
/* Copy thresholds and find current threshold */
- atomic_set(&thresholds_new->current_threshold, -1);
- for (i = 0, j = 0; i < thresholds->size; i++) {
- if (thresholds->entries[i].eventfd == eventfd)
+ new->current_threshold = -1;
+ for (i = 0, j = 0; i < thresholds->primary->size; i++) {
+ if (thresholds->primary->entries[i].eventfd == eventfd)
continue;
- thresholds_new->entries[j] = thresholds->entries[i];
- if (thresholds_new->entries[j].threshold < usage) {
+ new->entries[j] = thresholds->primary->entries[i];
+ if (new->entries[j].threshold < usage) {
/*
- * thresholds_new->current_threshold will not be used
+ * new->current_threshold will not be used
* until rcu_assign_pointer(), so it's safe to increment
* it here.
*/
- atomic_inc(&thresholds_new->current_threshold);
+ ++new->current_threshold;
}
j++;
}
-assign:
- if (type == _MEM)
- rcu_assign_pointer(memcg->thresholds, thresholds_new);
- else
- rcu_assign_pointer(memcg->memsw_thresholds, thresholds_new);
+swap_buffers:
+ /* Swap primary and spare array */
+ thresholds->spare = thresholds->primary;
+ rcu_assign_pointer(thresholds->primary, new);
- /* To be sure that nobody uses thresholds before freeing it */
+ /* To be sure that nobody uses thresholds */
synchronize_rcu();
- kfree(thresholds);
-unlock:
mutex_unlock(&memcg->thresholds_lock);
+}
- return ret;
+static int mem_cgroup_oom_register_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd, const char *args)
+{
+ struct mem_cgroup *memcg = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup_eventfd_list *event;
+ int type = MEMFILE_TYPE(cft->private);
+
+ BUG_ON(type != _OOM_TYPE);
+ event = kmalloc(sizeof(*event), GFP_KERNEL);
+ if (!event)
+ return -ENOMEM;
+
+ mutex_lock(&memcg_oom_mutex);
+
+ event->eventfd = eventfd;
+ list_add(&event->list, &memcg->oom_notify);
+
+ /* already in OOM ? */
+ if (atomic_read(&memcg->oom_lock))
+ eventfd_signal(eventfd, 1);
+ mutex_unlock(&memcg_oom_mutex);
+
+ return 0;
+}
+
+static void mem_cgroup_oom_unregister_event(struct cgroup *cgrp,
+ struct cftype *cft, struct eventfd_ctx *eventfd)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup_eventfd_list *ev, *tmp;
+ int type = MEMFILE_TYPE(cft->private);
+
+ BUG_ON(type != _OOM_TYPE);
+
+ mutex_lock(&memcg_oom_mutex);
+
+ list_for_each_entry_safe(ev, tmp, &mem->oom_notify, list) {
+ if (ev->eventfd == eventfd) {
+ list_del(&ev->list);
+ kfree(ev);
+ }
+ }
+
+ mutex_unlock(&memcg_oom_mutex);
+}
+
+static int mem_cgroup_oom_control_read(struct cgroup *cgrp,
+ struct cftype *cft, struct cgroup_map_cb *cb)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+
+ cb->fill(cb, "oom_kill_disable", mem->oom_kill_disable);
+
+ if (atomic_read(&mem->oom_lock))
+ cb->fill(cb, "under_oom", 1);
+ else
+ cb->fill(cb, "under_oom", 0);
+ return 0;
+}
+
+/*
+ */
+static int mem_cgroup_oom_control_write(struct cgroup *cgrp,
+ struct cftype *cft, u64 val)
+{
+ struct mem_cgroup *mem = mem_cgroup_from_cont(cgrp);
+ struct mem_cgroup *parent;
+
+ /* cannot set to root cgroup and only 0 and 1 are allowed */
+ if (!cgrp->parent || !((val == 0) || (val == 1)))
+ return -EINVAL;
+
+ parent = mem_cgroup_from_cont(cgrp->parent);
+
+ cgroup_lock();
+ /* oom-kill-disable is a flag for subhierarchy. */
+ if ((parent->use_hierarchy) ||
+ (mem->use_hierarchy && !list_empty(&cgrp->children))) {
+ cgroup_unlock();
+ return -EINVAL;
+ }
+ mem->oom_kill_disable = val;
+ cgroup_unlock();
+ return 0;
}
static struct cftype mem_cgroup_files[] = {
@@ -3544,8 +3790,8 @@ static struct cftype mem_cgroup_files[] = {
.name = "usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEM, RES_USAGE),
.read_u64 = mem_cgroup_read,
- .register_event = mem_cgroup_register_event,
- .unregister_event = mem_cgroup_unregister_event,
+ .register_event = mem_cgroup_usage_register_event,
+ .unregister_event = mem_cgroup_usage_unregister_event,
},
{
.name = "max_usage_in_bytes",
@@ -3594,6 +3840,14 @@ static struct cftype mem_cgroup_files[] = {
.read_u64 = mem_cgroup_move_charge_read,
.write_u64 = mem_cgroup_move_charge_write,
},
+ {
+ .name = "oom_control",
+ .read_map = mem_cgroup_oom_control_read,
+ .write_u64 = mem_cgroup_oom_control_write,
+ .register_event = mem_cgroup_oom_register_event,
+ .unregister_event = mem_cgroup_oom_unregister_event,
+ .private = MEMFILE_PRIVATE(_OOM_TYPE, OOM_CONTROL),
+ },
};
#ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP
@@ -3602,8 +3856,8 @@ static struct cftype memsw_cgroup_files[] = {
.name = "memsw.usage_in_bytes",
.private = MEMFILE_PRIVATE(_MEMSWAP, RES_USAGE),
.read_u64 = mem_cgroup_read,
- .register_event = mem_cgroup_register_event,
- .unregister_event = mem_cgroup_unregister_event,
+ .register_event = mem_cgroup_usage_register_event,
+ .unregister_event = mem_cgroup_usage_unregister_event,
},
{
.name = "memsw.max_usage_in_bytes",
@@ -3831,6 +4085,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
} else {
parent = mem_cgroup_from_cont(cont->parent);
mem->use_hierarchy = parent->use_hierarchy;
+ mem->oom_kill_disable = parent->oom_kill_disable;
}
if (parent && parent->use_hierarchy) {
@@ -3849,6 +4104,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont)
}
mem->last_scanned_child = 0;
spin_lock_init(&mem->reclaim_param_lock);
+ INIT_LIST_HEAD(&mem->oom_notify);
if (parent)
mem->swappiness = get_swappiness(parent);
@@ -3976,6 +4232,80 @@ enum mc_target_type {
MC_TARGET_SWAP,
};
+static struct page *mc_handle_present_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent)
+{
+ struct page *page = vm_normal_page(vma, addr, ptent);
+
+ if (!page || !page_mapped(page))
+ return NULL;
+ if (PageAnon(page)) {
+ /* we don't move shared anon */
+ if (!move_anon() || page_mapcount(page) > 2)
+ return NULL;
+ } else if (!move_file())
+ /* we ignore mapcount for file pages */
+ return NULL;
+ if (!get_page_unless_zero(page))
+ return NULL;
+
+ return page;
+}
+
+static struct page *mc_handle_swap_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent, swp_entry_t *entry)
+{
+ int usage_count;
+ struct page *page = NULL;
+ swp_entry_t ent = pte_to_swp_entry(ptent);
+
+ if (!move_anon() || non_swap_entry(ent))
+ return NULL;
+ usage_count = mem_cgroup_count_swap_user(ent, &page);
+ if (usage_count > 1) { /* we don't move shared anon */
+ if (page)
+ put_page(page);
+ return NULL;
+ }
+ if (do_swap_account)
+ entry->val = ent.val;
+
+ return page;
+}
+
+static struct page *mc_handle_file_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t ptent, swp_entry_t *entry)
+{
+ struct page *page = NULL;
+ struct inode *inode;
+ struct address_space *mapping;
+ pgoff_t pgoff;
+
+ if (!vma->vm_file) /* anonymous vma */
+ return NULL;
+ if (!move_file())
+ return NULL;
+
+ inode = vma->vm_file->f_path.dentry->d_inode;
+ mapping = vma->vm_file->f_mapping;
+ if (pte_none(ptent))
+ pgoff = linear_page_index(vma, addr);
+ else /* pte_file(ptent) is true */
+ pgoff = pte_to_pgoff(ptent);
+
+ /* page is moved even if it's not RSS of this task(page-faulted). */
+ if (!mapping_cap_swap_backed(mapping)) { /* normal file */
+ page = find_get_page(mapping, pgoff);
+ } else { /* shmem/tmpfs file. we should take account of swap too. */
+ swp_entry_t ent;
+ mem_cgroup_get_shmem_target(inode, pgoff, &page, &ent);
+ if (do_swap_account)
+ entry->val = ent.val;
+ }
+
+ return page;
+}
+
static int is_target_pte_for_mc(struct vm_area_struct *vma,
unsigned long addr, pte_t ptent, union mc_target *target)
{
@@ -3983,43 +4313,16 @@ static int is_target_pte_for_mc(struct vm_area_struct *vma,
struct page_cgroup *pc;
int ret = 0;
swp_entry_t ent = { .val = 0 };
- int usage_count = 0;
- bool move_anon = test_bit(MOVE_CHARGE_TYPE_ANON,
- &mc.to->move_charge_at_immigrate);
- if (!pte_present(ptent)) {
- /* TODO: handle swap of shmes/tmpfs */
- if (pte_none(ptent) || pte_file(ptent))
- return 0;
- else if (is_swap_pte(ptent)) {
- ent = pte_to_swp_entry(ptent);
- if (!move_anon || non_swap_entry(ent))
- return 0;
- usage_count = mem_cgroup_count_swap_user(ent, &page);
- }
- } else {
- page = vm_normal_page(vma, addr, ptent);
- if (!page || !page_mapped(page))
- return 0;
- /*
- * TODO: We don't move charges of file(including shmem/tmpfs)
- * pages for now.
- */
- if (!move_anon || !PageAnon(page))
- return 0;
- if (!get_page_unless_zero(page))
- return 0;
- usage_count = page_mapcount(page);
- }
- if (usage_count > 1) {
- /*
- * TODO: We don't move charges of shared(used by multiple
- * processes) pages for now.
- */
- if (page)
- put_page(page);
+ if (pte_present(ptent))
+ page = mc_handle_present_pte(vma, addr, ptent);
+ else if (is_swap_pte(ptent))
+ page = mc_handle_swap_pte(vma, addr, ptent, &ent);
+ else if (pte_none(ptent) || pte_file(ptent))
+ page = mc_handle_file_pte(vma, addr, ptent, &ent);
+
+ if (!page && !ent.val)
return 0;
- }
if (page) {
pc = lookup_page_cgroup(page);
/*
@@ -4035,8 +4338,8 @@ static int is_target_pte_for_mc(struct vm_area_struct *vma,
if (!ret || !target)
put_page(page);
}
- /* throught */
- if (ent.val && do_swap_account && !ret &&
+ /* There is a swap entry and a page doesn't exist or isn't charged */
+ if (ent.val && !ret &&
css_id(&mc.from->css) == lookup_swap_cgroup(ent)) {
ret = MC_TARGET_SWAP;
if (target)
@@ -4077,9 +4380,6 @@ static unsigned long mem_cgroup_count_precharge(struct mm_struct *mm)
};
if (is_vm_hugetlb_page(vma))
continue;
- /* TODO: We don't move charges of shmem/tmpfs pages for now. */
- if (vma->vm_flags & VM_SHARED)
- continue;
walk_page_range(vma->vm_start, vma->vm_end,
&mem_cgroup_count_precharge_walk);
}
@@ -4102,6 +4402,7 @@ static void mem_cgroup_clear_mc(void)
if (mc.precharge) {
__mem_cgroup_cancel_charge(mc.to, mc.precharge);
mc.precharge = 0;
+ memcg_oom_recover(mc.to);
}
/*
* we didn't uncharge from mc.from at mem_cgroup_move_account(), so
@@ -4110,6 +4411,7 @@ static void mem_cgroup_clear_mc(void)
if (mc.moved_charge) {
__mem_cgroup_cancel_charge(mc.from, mc.moved_charge);
mc.moved_charge = 0;
+ memcg_oom_recover(mc.from);
}
/* we must fixup refcnts and charges */
if (mc.moved_swap) {
@@ -4274,9 +4576,6 @@ static void mem_cgroup_move_charge(struct mm_struct *mm)
};
if (is_vm_hugetlb_page(vma))
continue;
- /* TODO: We don't move charges of shmem/tmpfs pages for now. */
- if (vma->vm_flags & VM_SHARED)
- continue;
ret = walk_page_range(vma->vm_start, vma->vm_end,
&mem_cgroup_move_charge_walk);
if (ret)
diff --git a/mm/memory.c b/mm/memory.c
index 833952d8b74..119b7ccdf39 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1227,8 +1227,17 @@ int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
}
EXPORT_SYMBOL_GPL(zap_vma_ptes);
-/*
- * Do a quick page-table lookup for a single page.
+/**
+ * follow_page - look up a page descriptor from a user-virtual address
+ * @vma: vm_area_struct mapping @address
+ * @address: virtual address to look up
+ * @flags: flags modifying lookup behaviour
+ *
+ * @flags can have FOLL_ flags set, defined in <linux/mm.h>
+ *
+ * Returns the mapped (struct page *), %NULL if no mapping exists, or
+ * an error pointer if there is a mapping to something not represented
+ * by a page descriptor (see also vm_normal_page()).
*/
struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
unsigned int flags)
diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c
index be211a58293..a4cfcdc0045 100644
--- a/mm/memory_hotplug.c
+++ b/mm/memory_hotplug.c
@@ -415,12 +415,14 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
* This means the page allocator ignores this zone.
* So, zonelist must be updated after online.
*/
+ mutex_lock(&zonelists_mutex);
if (!populated_zone(zone))
need_zonelists_rebuild = 1;
ret = walk_system_ram_range(pfn, nr_pages, &onlined_pages,
online_pages_range);
if (ret) {
+ mutex_unlock(&zonelists_mutex);
printk(KERN_DEBUG "online_pages %lx at %lx failed\n",
nr_pages, pfn);
memory_notify(MEM_CANCEL_ONLINE, &arg);
@@ -429,8 +431,12 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
zone->present_pages += onlined_pages;
zone->zone_pgdat->node_present_pages += onlined_pages;
+ if (need_zonelists_rebuild)
+ build_all_zonelists(zone);
+ else
+ zone_pcp_update(zone);
- zone_pcp_update(zone);
+ mutex_unlock(&zonelists_mutex);
setup_per_zone_wmarks();
calculate_zone_inactive_ratio(zone);
if (onlined_pages) {
@@ -438,10 +444,7 @@ int online_pages(unsigned long pfn, unsigned long nr_pages)
node_set_state(zone_to_nid(zone), N_HIGH_MEMORY);
}
- if (need_zonelists_rebuild)
- build_all_zonelists();
- else
- vm_total_pages = nr_free_pagecache_pages();
+ vm_total_pages = nr_free_pagecache_pages();
writeback_set_ratelimit();
@@ -482,6 +485,29 @@ static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
}
+/*
+ * called by cpu_up() to online a node without onlined memory.
+ */
+int mem_online_node(int nid)
+{
+ pg_data_t *pgdat;
+ int ret;
+
+ lock_system_sleep();
+ pgdat = hotadd_new_pgdat(nid, 0);
+ if (pgdat) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ node_set_online(nid);
+ ret = register_one_node(nid);
+ BUG_ON(ret);
+
+out:
+ unlock_system_sleep();
+ return ret;
+}
+
/* we are OK calling __meminit stuff here - we have CONFIG_MEMORY_HOTPLUG */
int __ref add_memory(int nid, u64 start, u64 size)
{
diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 08f40a2f3fe..5d6fb339de0 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -119,7 +119,22 @@ struct mempolicy default_policy = {
static const struct mempolicy_operations {
int (*create)(struct mempolicy *pol, const nodemask_t *nodes);
- void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes);
+ /*
+ * If read-side task has no lock to protect task->mempolicy, write-side
+ * task will rebind the task->mempolicy by two step. The first step is
+ * setting all the newly nodes, and the second step is cleaning all the
+ * disallowed nodes. In this way, we can avoid finding no node to alloc
+ * page.
+ * If we have a lock to protect task->mempolicy in read-side, we do
+ * rebind directly.
+ *
+ * step:
+ * MPOL_REBIND_ONCE - do rebind work at once
+ * MPOL_REBIND_STEP1 - set all the newly nodes
+ * MPOL_REBIND_STEP2 - clean all the disallowed nodes
+ */
+ void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes,
+ enum mpol_rebind_step step);
} mpol_ops[MPOL_MAX];
/* Check that the nodemask contains at least one populated zone */
@@ -127,9 +142,6 @@ static int is_valid_nodemask(const nodemask_t *nodemask)
{
int nd, k;
- /* Check that there is something useful in this mask */
- k = policy_zone;
-
for_each_node_mask(nd, *nodemask) {
struct zone *z;
@@ -145,7 +157,7 @@ static int is_valid_nodemask(const nodemask_t *nodemask)
static inline int mpol_store_user_nodemask(const struct mempolicy *pol)
{
- return pol->flags & (MPOL_F_STATIC_NODES | MPOL_F_RELATIVE_NODES);
+ return pol->flags & MPOL_MODE_FLAGS;
}
static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig,
@@ -277,12 +289,19 @@ void __mpol_put(struct mempolicy *p)
kmem_cache_free(policy_cache, p);
}
-static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes)
+static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes,
+ enum mpol_rebind_step step)
{
}
-static void mpol_rebind_nodemask(struct mempolicy *pol,
- const nodemask_t *nodes)
+/*
+ * step:
+ * MPOL_REBIND_ONCE - do rebind work at once
+ * MPOL_REBIND_STEP1 - set all the newly nodes
+ * MPOL_REBIND_STEP2 - clean all the disallowed nodes
+ */
+static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes,
+ enum mpol_rebind_step step)
{
nodemask_t tmp;
@@ -291,12 +310,31 @@ static void mpol_rebind_nodemask(struct mempolicy *pol,
else if (pol->flags & MPOL_F_RELATIVE_NODES)
mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes);
else {
- nodes_remap(tmp, pol->v.nodes, pol->w.cpuset_mems_allowed,
- *nodes);
- pol->w.cpuset_mems_allowed = *nodes;
+ /*
+ * if step == 1, we use ->w.cpuset_mems_allowed to cache the
+ * result
+ */
+ if (step == MPOL_REBIND_ONCE || step == MPOL_REBIND_STEP1) {
+ nodes_remap(tmp, pol->v.nodes,
+ pol->w.cpuset_mems_allowed, *nodes);
+ pol->w.cpuset_mems_allowed = step ? tmp : *nodes;
+ } else if (step == MPOL_REBIND_STEP2) {
+ tmp = pol->w.cpuset_mems_allowed;
+ pol->w.cpuset_mems_allowed = *nodes;
+ } else
+ BUG();
}
- pol->v.nodes = tmp;
+ if (nodes_empty(tmp))
+ tmp = *nodes;
+
+ if (step == MPOL_REBIND_STEP1)
+ nodes_or(pol->v.nodes, pol->v.nodes, tmp);
+ else if (step == MPOL_REBIND_ONCE || step == MPOL_REBIND_STEP2)
+ pol->v.nodes = tmp;
+ else
+ BUG();
+
if (!node_isset(current->il_next, tmp)) {
current->il_next = next_node(current->il_next, tmp);
if (current->il_next >= MAX_NUMNODES)
@@ -307,7 +345,8 @@ static void mpol_rebind_nodemask(struct mempolicy *pol,
}
static void mpol_rebind_preferred(struct mempolicy *pol,
- const nodemask_t *nodes)
+ const nodemask_t *nodes,
+ enum mpol_rebind_step step)
{
nodemask_t tmp;
@@ -330,16 +369,45 @@ static void mpol_rebind_preferred(struct mempolicy *pol,
}
}
-/* Migrate a policy to a different set of nodes */
-static void mpol_rebind_policy(struct mempolicy *pol,
- const nodemask_t *newmask)
+/*
+ * mpol_rebind_policy - Migrate a policy to a different set of nodes
+ *
+ * If read-side task has no lock to protect task->mempolicy, write-side
+ * task will rebind the task->mempolicy by two step. The first step is
+ * setting all the newly nodes, and the second step is cleaning all the
+ * disallowed nodes. In this way, we can avoid finding no node to alloc
+ * page.
+ * If we have a lock to protect task->mempolicy in read-side, we do
+ * rebind directly.
+ *
+ * step:
+ * MPOL_REBIND_ONCE - do rebind work at once
+ * MPOL_REBIND_STEP1 - set all the newly nodes
+ * MPOL_REBIND_STEP2 - clean all the disallowed nodes
+ */
+static void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask,
+ enum mpol_rebind_step step)
{
if (!pol)
return;
- if (!mpol_store_user_nodemask(pol) &&
+ if (!mpol_store_user_nodemask(pol) && step == 0 &&
nodes_equal(pol->w.cpuset_mems_allowed, *newmask))
return;
- mpol_ops[pol->mode].rebind(pol, newmask);
+
+ if (step == MPOL_REBIND_STEP1 && (pol->flags & MPOL_F_REBINDING))
+ return;
+
+ if (step == MPOL_REBIND_STEP2 && !(pol->flags & MPOL_F_REBINDING))
+ BUG();
+
+ if (step == MPOL_REBIND_STEP1)
+ pol->flags |= MPOL_F_REBINDING;
+ else if (step == MPOL_REBIND_STEP2)
+ pol->flags &= ~MPOL_F_REBINDING;
+ else if (step >= MPOL_REBIND_NSTEP)
+ BUG();
+
+ mpol_ops[pol->mode].rebind(pol, newmask, step);
}
/*
@@ -349,9 +417,10 @@ static void mpol_rebind_policy(struct mempolicy *pol,
* Called with task's alloc_lock held.
*/
-void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new)
+void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new,
+ enum mpol_rebind_step step)
{
- mpol_rebind_policy(tsk->mempolicy, new);
+ mpol_rebind_policy(tsk->mempolicy, new, step);
}
/*
@@ -366,7 +435,7 @@ void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new)
down_write(&mm->mmap_sem);
for (vma = mm->mmap; vma; vma = vma->vm_next)
- mpol_rebind_policy(vma->vm_policy, new);
+ mpol_rebind_policy(vma->vm_policy, new, MPOL_REBIND_ONCE);
up_write(&mm->mmap_sem);
}
@@ -859,7 +928,7 @@ static int migrate_to_node(struct mm_struct *mm, int source, int dest,
nodes_clear(nmask);
node_set(source, nmask);
- check_range(mm, mm->mmap->vm_start, TASK_SIZE, &nmask,
+ check_range(mm, mm->mmap->vm_start, mm->task_size, &nmask,
flags | MPOL_MF_DISCONTIG_OK, &pagelist);
if (!list_empty(&pagelist))
@@ -1444,15 +1513,13 @@ static struct zonelist *policy_zonelist(gfp_t gfp, struct mempolicy *policy)
/*
* Normally, MPOL_BIND allocations are node-local within the
* allowed nodemask. However, if __GFP_THISNODE is set and the
- * current node is part of the mask, we use the zonelist for
+ * current node isn't part of the mask, we use the zonelist for
* the first node in the mask instead.
*/
if (unlikely(gfp & __GFP_THISNODE) &&
unlikely(!node_isset(nd, policy->v.nodes)))
nd = first_node(policy->v.nodes);
break;
- case MPOL_INTERLEAVE: /* should not happen */
- break;
default:
BUG();
}
@@ -1572,6 +1639,8 @@ static inline unsigned interleave_nid(struct mempolicy *pol,
* to the struct mempolicy for conditional unref after allocation.
* If the effective policy is 'BIND, returns a pointer to the mempolicy's
* @nodemask for filtering the zonelist.
+ *
+ * Must be protected by get_mems_allowed()
*/
struct zonelist *huge_zonelist(struct vm_area_struct *vma, unsigned long addr,
gfp_t gfp_flags, struct mempolicy **mpol,
@@ -1617,6 +1686,7 @@ bool init_nodemask_of_mempolicy(nodemask_t *mask)
if (!(mask && current->mempolicy))
return false;
+ task_lock(current);
mempolicy = current->mempolicy;
switch (mempolicy->mode) {
case MPOL_PREFERRED:
@@ -1636,6 +1706,7 @@ bool init_nodemask_of_mempolicy(nodemask_t *mask)
default:
BUG();
}
+ task_unlock(current);
return true;
}
@@ -1683,13 +1754,17 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
{
struct mempolicy *pol = get_vma_policy(current, vma, addr);
struct zonelist *zl;
+ struct page *page;
+ get_mems_allowed();
if (unlikely(pol->mode == MPOL_INTERLEAVE)) {
unsigned nid;
nid = interleave_nid(pol, vma, addr, PAGE_SHIFT);
mpol_cond_put(pol);
- return alloc_page_interleave(gfp, 0, nid);
+ page = alloc_page_interleave(gfp, 0, nid);
+ put_mems_allowed();
+ return page;
}
zl = policy_zonelist(gfp, pol);
if (unlikely(mpol_needs_cond_ref(pol))) {
@@ -1699,12 +1774,15 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
struct page *page = __alloc_pages_nodemask(gfp, 0,
zl, policy_nodemask(gfp, pol));
__mpol_put(pol);
+ put_mems_allowed();
return page;
}
/*
* fast path: default or task policy
*/
- return __alloc_pages_nodemask(gfp, 0, zl, policy_nodemask(gfp, pol));
+ page = __alloc_pages_nodemask(gfp, 0, zl, policy_nodemask(gfp, pol));
+ put_mems_allowed();
+ return page;
}
/**
@@ -1729,18 +1807,23 @@ alloc_page_vma(gfp_t gfp, struct vm_area_struct *vma, unsigned long addr)
struct page *alloc_pages_current(gfp_t gfp, unsigned order)
{
struct mempolicy *pol = current->mempolicy;
+ struct page *page;
if (!pol || in_interrupt() || (gfp & __GFP_THISNODE))
pol = &default_policy;
+ get_mems_allowed();
/*
* No reference counting needed for current->mempolicy
* nor system default_policy
*/
if (pol->mode == MPOL_INTERLEAVE)
- return alloc_page_interleave(gfp, order, interleave_nodes(pol));
- return __alloc_pages_nodemask(gfp, order,
+ page = alloc_page_interleave(gfp, order, interleave_nodes(pol));
+ else
+ page = __alloc_pages_nodemask(gfp, order,
policy_zonelist(gfp, pol), policy_nodemask(gfp, pol));
+ put_mems_allowed();
+ return page;
}
EXPORT_SYMBOL(alloc_pages_current);
@@ -1750,6 +1833,9 @@ EXPORT_SYMBOL(alloc_pages_current);
* with the mems_allowed returned by cpuset_mems_allowed(). This
* keeps mempolicies cpuset relative after its cpuset moves. See
* further kernel/cpuset.c update_nodemask().
+ *
+ * current's mempolicy may be rebinded by the other task(the task that changes
+ * cpuset's mems), so we needn't do rebind work for current task.
*/
/* Slow path of a mempolicy duplicate */
@@ -1759,13 +1845,24 @@ struct mempolicy *__mpol_dup(struct mempolicy *old)
if (!new)
return ERR_PTR(-ENOMEM);
+
+ /* task's mempolicy is protected by alloc_lock */
+ if (old == current->mempolicy) {
+ task_lock(current);
+ *new = *old;
+ task_unlock(current);
+ } else
+ *new = *old;
+
rcu_read_lock();
if (current_cpuset_is_being_rebound()) {
nodemask_t mems = cpuset_mems_allowed(current);
- mpol_rebind_policy(old, &mems);
+ if (new->flags & MPOL_F_REBINDING)
+ mpol_rebind_policy(new, &mems, MPOL_REBIND_STEP2);
+ else
+ mpol_rebind_policy(new, &mems, MPOL_REBIND_ONCE);
}
rcu_read_unlock();
- *new = *old;
atomic_set(&new->refcnt, 1);
return new;
}
@@ -1792,16 +1889,6 @@ struct mempolicy *__mpol_cond_copy(struct mempolicy *tompol,
return tompol;
}
-static int mpol_match_intent(const struct mempolicy *a,
- const struct mempolicy *b)
-{
- if (a->flags != b->flags)
- return 0;
- if (!mpol_store_user_nodemask(a))
- return 1;
- return nodes_equal(a->w.user_nodemask, b->w.user_nodemask);
-}
-
/* Slow path of a mempolicy comparison */
int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
{
@@ -1809,8 +1896,12 @@ int __mpol_equal(struct mempolicy *a, struct mempolicy *b)
return 0;
if (a->mode != b->mode)
return 0;
- if (a->mode != MPOL_DEFAULT && !mpol_match_intent(a, b))
+ if (a->flags != b->flags)
return 0;
+ if (mpol_store_user_nodemask(a))
+ if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask))
+ return 0;
+
switch (a->mode) {
case MPOL_BIND:
/* Fall through */
@@ -2006,27 +2097,24 @@ void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
return;
/* contextualize the tmpfs mount point mempolicy */
new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
- if (IS_ERR(new)) {
- mpol_put(mpol); /* drop our ref on sb mpol */
- NODEMASK_SCRATCH_FREE(scratch);
- return; /* no valid nodemask intersection */
- }
+ if (IS_ERR(new))
+ goto free_scratch; /* no valid nodemask intersection */
task_lock(current);
ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch);
task_unlock(current);
mpol_put(mpol); /* drop our ref on sb mpol */
- if (ret) {
- NODEMASK_SCRATCH_FREE(scratch);
- mpol_put(new);
- return;
- }
+ if (ret)
+ goto put_free;
/* Create pseudo-vma that contains just the policy */
memset(&pvma, 0, sizeof(struct vm_area_struct));
pvma.vm_end = TASK_SIZE; /* policy covers entire file */
mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
+
+put_free:
mpol_put(new); /* drop initial ref */
+free_scratch:
NODEMASK_SCRATCH_FREE(scratch);
}
}
@@ -2132,9 +2220,15 @@ void numa_default_policy(void)
* "local" is pseudo-policy: MPOL_PREFERRED with MPOL_F_LOCAL flag
* Used only for mpol_parse_str() and mpol_to_str()
*/
-#define MPOL_LOCAL (MPOL_INTERLEAVE + 1)
-static const char * const policy_types[] =
- { "default", "prefer", "bind", "interleave", "local" };
+#define MPOL_LOCAL MPOL_MAX
+static const char * const policy_modes[] =
+{
+ [MPOL_DEFAULT] = "default",
+ [MPOL_PREFERRED] = "prefer",
+ [MPOL_BIND] = "bind",
+ [MPOL_INTERLEAVE] = "interleave",
+ [MPOL_LOCAL] = "local"
+};
#ifdef CONFIG_TMPFS
@@ -2159,12 +2253,11 @@ static const char * const policy_types[] =
int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
{
struct mempolicy *new = NULL;
- unsigned short uninitialized_var(mode);
+ unsigned short mode;
unsigned short uninitialized_var(mode_flags);
nodemask_t nodes;
char *nodelist = strchr(str, ':');
char *flags = strchr(str, '=');
- int i;
int err = 1;
if (nodelist) {
@@ -2180,13 +2273,12 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
if (flags)
*flags++ = '\0'; /* terminate mode string */
- for (i = 0; i <= MPOL_LOCAL; i++) {
- if (!strcmp(str, policy_types[i])) {
- mode = i;
+ for (mode = 0; mode <= MPOL_LOCAL; mode++) {
+ if (!strcmp(str, policy_modes[mode])) {
break;
}
}
- if (i > MPOL_LOCAL)
+ if (mode > MPOL_LOCAL)
goto out;
switch (mode) {
@@ -2250,7 +2342,10 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
if (IS_ERR(new))
goto out;
- {
+ if (no_context) {
+ /* save for contextualization */
+ new->w.user_nodemask = nodes;
+ } else {
int ret;
NODEMASK_SCRATCH(scratch);
if (scratch) {
@@ -2266,10 +2361,6 @@ int mpol_parse_str(char *str, struct mempolicy **mpol, int no_context)
}
}
err = 0;
- if (no_context) {
- /* save for contextualization */
- new->w.user_nodemask = nodes;
- }
out:
/* Restore string for error message */
@@ -2338,11 +2429,11 @@ int mpol_to_str(char *buffer, int maxlen, struct mempolicy *pol, int no_context)
BUG();
}
- l = strlen(policy_types[mode]);
+ l = strlen(policy_modes[mode]);
if (buffer + maxlen < p + l + 1)
return -ENOSPC;
- strcpy(p, policy_types[mode]);
+ strcpy(p, policy_modes[mode]);
p += l;
if (flags & MPOL_MODE_FLAGS) {
diff --git a/mm/migrate.c b/mm/migrate.c
index d3f3f7f8107..4205b1d6049 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -40,7 +40,8 @@
/*
* migrate_prep() needs to be called before we start compiling a list of pages
- * to be migrated using isolate_lru_page().
+ * to be migrated using isolate_lru_page(). If scheduling work on other CPUs is
+ * undesirable, use migrate_prep_local()
*/
int migrate_prep(void)
{
@@ -55,26 +56,29 @@ int migrate_prep(void)
return 0;
}
+/* Do the necessary work of migrate_prep but not if it involves other CPUs */
+int migrate_prep_local(void)
+{
+ lru_add_drain();
+
+ return 0;
+}
+
/*
* Add isolated pages on the list back to the LRU under page lock
* to avoid leaking evictable pages back onto unevictable list.
- *
- * returns the number of pages put back.
*/
-int putback_lru_pages(struct list_head *l)
+void putback_lru_pages(struct list_head *l)
{
struct page *page;
struct page *page2;
- int count = 0;
list_for_each_entry_safe(page, page2, l, lru) {
list_del(&page->lru);
dec_zone_page_state(page, NR_ISOLATED_ANON +
page_is_file_cache(page));
putback_lru_page(page);
- count++;
}
- return count;
}
/*
@@ -490,7 +494,8 @@ static int fallback_migrate_page(struct address_space *mapping,
* < 0 - error code
* == 0 - success
*/
-static int move_to_new_page(struct page *newpage, struct page *page)
+static int move_to_new_page(struct page *newpage, struct page *page,
+ int remap_swapcache)
{
struct address_space *mapping;
int rc;
@@ -525,10 +530,12 @@ static int move_to_new_page(struct page *newpage, struct page *page)
else
rc = fallback_migrate_page(mapping, newpage, page);
- if (!rc)
- remove_migration_ptes(page, newpage);
- else
+ if (rc) {
newpage->mapping = NULL;
+ } else {
+ if (remap_swapcache)
+ remove_migration_ptes(page, newpage);
+ }
unlock_page(newpage);
@@ -545,9 +552,11 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
int rc = 0;
int *result = NULL;
struct page *newpage = get_new_page(page, private, &result);
+ int remap_swapcache = 1;
int rcu_locked = 0;
int charge = 0;
struct mem_cgroup *mem = NULL;
+ struct anon_vma *anon_vma = NULL;
if (!newpage)
return -ENOMEM;
@@ -581,7 +590,7 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
}
/* charge against new page */
- charge = mem_cgroup_prepare_migration(page, &mem);
+ charge = mem_cgroup_prepare_migration(page, newpage, &mem);
if (charge == -ENOMEM) {
rc = -ENOMEM;
goto unlock;
@@ -604,6 +613,34 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
if (PageAnon(page)) {
rcu_read_lock();
rcu_locked = 1;
+
+ /* Determine how to safely use anon_vma */
+ if (!page_mapped(page)) {
+ if (!PageSwapCache(page))
+ goto rcu_unlock;
+
+ /*
+ * We cannot be sure that the anon_vma of an unmapped
+ * swapcache page is safe to use because we don't
+ * know in advance if the VMA that this page belonged
+ * to still exists. If the VMA and others sharing the
+ * data have been freed, then the anon_vma could
+ * already be invalid.
+ *
+ * To avoid this possibility, swapcache pages get
+ * migrated but are not remapped when migration
+ * completes
+ */
+ remap_swapcache = 0;
+ } else {
+ /*
+ * Take a reference count on the anon_vma if the
+ * page is mapped so that it is guaranteed to
+ * exist when the page is remapped later
+ */
+ anon_vma = page_anon_vma(page);
+ atomic_inc(&anon_vma->external_refcount);
+ }
}
/*
@@ -638,11 +675,20 @@ static int unmap_and_move(new_page_t get_new_page, unsigned long private,
skip_unmap:
if (!page_mapped(page))
- rc = move_to_new_page(newpage, page);
+ rc = move_to_new_page(newpage, page, remap_swapcache);
- if (rc)
+ if (rc && remap_swapcache)
remove_migration_ptes(page, page);
rcu_unlock:
+
+ /* Drop an anon_vma reference if we took one */
+ if (anon_vma && atomic_dec_and_lock(&anon_vma->external_refcount, &anon_vma->lock)) {
+ int empty = list_empty(&anon_vma->head);
+ spin_unlock(&anon_vma->lock);
+ if (empty)
+ anon_vma_free(anon_vma);
+ }
+
if (rcu_locked)
rcu_read_unlock();
uncharge:
diff --git a/mm/mincore.c b/mm/mincore.c
index f77433c2027..9ac42dc6d7b 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -19,6 +19,40 @@
#include <asm/uaccess.h>
#include <asm/pgtable.h>
+static void mincore_hugetlb_page_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
+{
+#ifdef CONFIG_HUGETLB_PAGE
+ struct hstate *h;
+
+ h = hstate_vma(vma);
+ while (1) {
+ unsigned char present;
+ pte_t *ptep;
+ /*
+ * Huge pages are always in RAM for now, but
+ * theoretically it needs to be checked.
+ */
+ ptep = huge_pte_offset(current->mm,
+ addr & huge_page_mask(h));
+ present = ptep && !huge_pte_none(huge_ptep_get(ptep));
+ while (1) {
+ *vec = present;
+ vec++;
+ addr += PAGE_SIZE;
+ if (addr == end)
+ return;
+ /* check hugepage border */
+ if (!(addr & ~huge_page_mask(h)))
+ break;
+ }
+ }
+#else
+ BUG();
+#endif
+}
+
/*
* Later we can get more picky about what "in core" means precisely.
* For now, simply check to see if the page is in the page cache,
@@ -49,145 +83,150 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff)
return present;
}
-/*
- * Do a chunk of "sys_mincore()". We've already checked
- * all the arguments, we hold the mmap semaphore: we should
- * just return the amount of info we're asked for.
- */
-static long do_mincore(unsigned long addr, unsigned char *vec, unsigned long pages)
+static void mincore_unmapped_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *ptep;
- spinlock_t *ptl;
- unsigned long nr;
+ unsigned long nr = (end - addr) >> PAGE_SHIFT;
int i;
- pgoff_t pgoff;
- struct vm_area_struct *vma = find_vma(current->mm, addr);
- /*
- * find_vma() didn't find anything above us, or we're
- * in an unmapped hole in the address space: ENOMEM.
- */
- if (!vma || addr < vma->vm_start)
- return -ENOMEM;
-
-#ifdef CONFIG_HUGETLB_PAGE
- if (is_vm_hugetlb_page(vma)) {
- struct hstate *h;
- unsigned long nr_huge;
- unsigned char present;
+ if (vma->vm_file) {
+ pgoff_t pgoff;
- i = 0;
- nr = min(pages, (vma->vm_end - addr) >> PAGE_SHIFT);
- h = hstate_vma(vma);
- nr_huge = ((addr + pages * PAGE_SIZE - 1) >> huge_page_shift(h))
- - (addr >> huge_page_shift(h)) + 1;
- nr_huge = min(nr_huge,
- (vma->vm_end - addr) >> huge_page_shift(h));
- while (1) {
- /* hugepage always in RAM for now,
- * but generally it needs to be check */
- ptep = huge_pte_offset(current->mm,
- addr & huge_page_mask(h));
- present = !!(ptep &&
- !huge_pte_none(huge_ptep_get(ptep)));
- while (1) {
- vec[i++] = present;
- addr += PAGE_SIZE;
- /* reach buffer limit */
- if (i == nr)
- return nr;
- /* check hugepage border */
- if (!((addr & ~huge_page_mask(h))
- >> PAGE_SHIFT))
- break;
- }
- }
- return nr;
+ pgoff = linear_page_index(vma, addr);
+ for (i = 0; i < nr; i++, pgoff++)
+ vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff);
+ } else {
+ for (i = 0; i < nr; i++)
+ vec[i] = 0;
}
-#endif
-
- /*
- * Calculate how many pages there are left in the last level of the
- * PTE array for our address.
- */
- nr = PTRS_PER_PTE - ((addr >> PAGE_SHIFT) & (PTRS_PER_PTE-1));
-
- /*
- * Don't overrun this vma
- */
- nr = min(nr, (vma->vm_end - addr) >> PAGE_SHIFT);
-
- /*
- * Don't return more than the caller asked for
- */
- nr = min(nr, pages);
+}
- pgd = pgd_offset(vma->vm_mm, addr);
- if (pgd_none_or_clear_bad(pgd))
- goto none_mapped;
- pud = pud_offset(pgd, addr);
- if (pud_none_or_clear_bad(pud))
- goto none_mapped;
- pmd = pmd_offset(pud, addr);
- if (pmd_none_or_clear_bad(pmd))
- goto none_mapped;
+static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
+{
+ unsigned long next;
+ spinlock_t *ptl;
+ pte_t *ptep;
ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
- for (i = 0; i < nr; i++, ptep++, addr += PAGE_SIZE) {
- unsigned char present;
+ do {
pte_t pte = *ptep;
+ pgoff_t pgoff;
- if (pte_present(pte)) {
- present = 1;
-
- } else if (pte_none(pte)) {
- if (vma->vm_file) {
- pgoff = linear_page_index(vma, addr);
- present = mincore_page(vma->vm_file->f_mapping,
- pgoff);
- } else
- present = 0;
-
- } else if (pte_file(pte)) {
+ next = addr + PAGE_SIZE;
+ if (pte_none(pte))
+ mincore_unmapped_range(vma, addr, next, vec);
+ else if (pte_present(pte))
+ *vec = 1;
+ else if (pte_file(pte)) {
pgoff = pte_to_pgoff(pte);
- present = mincore_page(vma->vm_file->f_mapping, pgoff);
-
+ *vec = mincore_page(vma->vm_file->f_mapping, pgoff);
} else { /* pte is a swap entry */
swp_entry_t entry = pte_to_swp_entry(pte);
+
if (is_migration_entry(entry)) {
/* migration entries are always uptodate */
- present = 1;
+ *vec = 1;
} else {
#ifdef CONFIG_SWAP
pgoff = entry.val;
- present = mincore_page(&swapper_space, pgoff);
+ *vec = mincore_page(&swapper_space, pgoff);
#else
WARN_ON(1);
- present = 1;
+ *vec = 1;
#endif
}
}
+ vec++;
+ } while (ptep++, addr = next, addr != end);
+ pte_unmap_unlock(ptep - 1, ptl);
+}
- vec[i] = present;
- }
- pte_unmap_unlock(ptep-1, ptl);
+static void mincore_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
+{
+ unsigned long next;
+ pmd_t *pmd;
- return nr;
+ pmd = pmd_offset(pud, addr);
+ do {
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(pmd))
+ mincore_unmapped_range(vma, addr, next, vec);
+ else
+ mincore_pte_range(vma, pmd, addr, next, vec);
+ vec += (next - addr) >> PAGE_SHIFT;
+ } while (pmd++, addr = next, addr != end);
+}
-none_mapped:
- if (vma->vm_file) {
- pgoff = linear_page_index(vma, addr);
- for (i = 0; i < nr; i++, pgoff++)
- vec[i] = mincore_page(vma->vm_file->f_mapping, pgoff);
- } else {
- for (i = 0; i < nr; i++)
- vec[i] = 0;
+static void mincore_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
+{
+ unsigned long next;
+ pud_t *pud;
+
+ pud = pud_offset(pgd, addr);
+ do {
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(pud))
+ mincore_unmapped_range(vma, addr, next, vec);
+ else
+ mincore_pmd_range(vma, pud, addr, next, vec);
+ vec += (next - addr) >> PAGE_SHIFT;
+ } while (pud++, addr = next, addr != end);
+}
+
+static void mincore_page_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end,
+ unsigned char *vec)
+{
+ unsigned long next;
+ pgd_t *pgd;
+
+ pgd = pgd_offset(vma->vm_mm, addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(pgd))
+ mincore_unmapped_range(vma, addr, next, vec);
+ else
+ mincore_pud_range(vma, pgd, addr, next, vec);
+ vec += (next - addr) >> PAGE_SHIFT;
+ } while (pgd++, addr = next, addr != end);
+}
+
+/*
+ * Do a chunk of "sys_mincore()". We've already checked
+ * all the arguments, we hold the mmap semaphore: we should
+ * just return the amount of info we're asked for.
+ */
+static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *vec)
+{
+ struct vm_area_struct *vma;
+ unsigned long end;
+
+ vma = find_vma(current->mm, addr);
+ if (!vma || addr < vma->vm_start)
+ return -ENOMEM;
+
+ end = min(vma->vm_end, addr + (pages << PAGE_SHIFT));
+
+ if (is_vm_hugetlb_page(vma)) {
+ mincore_hugetlb_page_range(vma, addr, end, vec);
+ return (end - addr) >> PAGE_SHIFT;
}
- return nr;
+ end = pmd_addr_end(addr, end);
+
+ if (is_vm_hugetlb_page(vma))
+ mincore_hugetlb_page_range(vma, addr, end, vec);
+ else
+ mincore_page_range(vma, addr, end, vec);
+
+ return (end - addr) >> PAGE_SHIFT;
}
/*
@@ -247,7 +286,7 @@ SYSCALL_DEFINE3(mincore, unsigned long, start, size_t, len,
* the temporary buffer size.
*/
down_read(&current->mm->mmap_sem);
- retval = do_mincore(start, tmp, min(pages, PAGE_SIZE));
+ retval = do_mincore(start, min(pages, PAGE_SIZE), tmp);
up_read(&current->mm->mmap_sem);
if (retval <= 0)
diff --git a/mm/nommu.c b/mm/nommu.c
index 63fa17d121f..b76f3ee0abe 100644
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -918,14 +918,6 @@ static int validate_mmap_request(struct file *file,
if (!(capabilities & BDI_CAP_MAP_DIRECT))
return -ENODEV;
- if (((prot & PROT_READ) && !(capabilities & BDI_CAP_READ_MAP)) ||
- ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) ||
- ((prot & PROT_EXEC) && !(capabilities & BDI_CAP_EXEC_MAP))
- ) {
- printk("MAP_SHARED not completely supported on !MMU\n");
- return -EINVAL;
- }
-
/* we mustn't privatise shared mappings */
capabilities &= ~BDI_CAP_MAP_COPY;
}
@@ -941,6 +933,20 @@ static int validate_mmap_request(struct file *file,
capabilities &= ~BDI_CAP_MAP_DIRECT;
}
+ if (capabilities & BDI_CAP_MAP_DIRECT) {
+ if (((prot & PROT_READ) && !(capabilities & BDI_CAP_READ_MAP)) ||
+ ((prot & PROT_WRITE) && !(capabilities & BDI_CAP_WRITE_MAP)) ||
+ ((prot & PROT_EXEC) && !(capabilities & BDI_CAP_EXEC_MAP))
+ ) {
+ capabilities &= ~BDI_CAP_MAP_DIRECT;
+ if (flags & MAP_SHARED) {
+ printk(KERN_WARNING
+ "MAP_SHARED not completely supported on !MMU\n");
+ return -EINVAL;
+ }
+ }
+ }
+
/* handle executable mappings and implied executable
* mappings */
if (file->f_path.mnt->mnt_flags & MNT_NOEXEC) {
@@ -996,22 +1002,20 @@ static unsigned long determine_vm_flags(struct file *file,
unsigned long vm_flags;
vm_flags = calc_vm_prot_bits(prot) | calc_vm_flag_bits(flags);
- vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
/* vm_flags |= mm->def_flags; */
if (!(capabilities & BDI_CAP_MAP_DIRECT)) {
/* attempt to share read-only copies of mapped file chunks */
+ vm_flags |= VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC;
if (file && !(prot & PROT_WRITE))
vm_flags |= VM_MAYSHARE;
- }
- else {
+ } else {
/* overlay a shareable mapping on the backing device or inode
* if possible - used for chardevs, ramfs/tmpfs/shmfs and
* romfs/cramfs */
+ vm_flags |= VM_MAYSHARE | (capabilities & BDI_CAP_VMFLAGS);
if (flags & MAP_SHARED)
- vm_flags |= VM_MAYSHARE | VM_SHARED;
- else if ((((vm_flags & capabilities) ^ vm_flags) & BDI_CAP_VMFLAGS) == 0)
- vm_flags |= VM_MAYSHARE;
+ vm_flags |= VM_SHARED;
}
/* refuse to let anyone share private mappings with this process if
diff --git a/mm/oom_kill.c b/mm/oom_kill.c
index b68e802a7a7..709aedfaa01 100644
--- a/mm/oom_kill.c
+++ b/mm/oom_kill.c
@@ -479,12 +479,9 @@ void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask)
read_lock(&tasklist_lock);
retry:
p = select_bad_process(&points, mem);
- if (PTR_ERR(p) == -1UL)
+ if (!p || PTR_ERR(p) == -1UL)
goto out;
- if (!p)
- p = current;
-
if (oom_kill_process(p, gfp_mask, 0, points, mem,
"Memory cgroup out of memory"))
goto retry;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index a6326c71b66..431214b941a 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -49,6 +49,7 @@
#include <linux/debugobjects.h>
#include <linux/kmemleak.h>
#include <linux/memory.h>
+#include <linux/compaction.h>
#include <trace/events/kmem.h>
#include <linux/ftrace_event.h>
@@ -56,6 +57,22 @@
#include <asm/div64.h>
#include "internal.h"
+#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
+DEFINE_PER_CPU(int, numa_node);
+EXPORT_PER_CPU_SYMBOL(numa_node);
+#endif
+
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+/*
+ * N.B., Do NOT reference the '_numa_mem_' per cpu variable directly.
+ * It will not be defined when CONFIG_HAVE_MEMORYLESS_NODES is not defined.
+ * Use the accessor functions set_numa_mem(), numa_mem_id() and cpu_to_mem()
+ * defined in <linux/topology.h>.
+ */
+DEFINE_PER_CPU(int, _numa_mem_); /* Kernel "local memory" node */
+EXPORT_PER_CPU_SYMBOL(_numa_mem_);
+#endif
+
/*
* Array of node states.
*/
@@ -475,6 +492,8 @@ static inline void __free_one_page(struct page *page,
int migratetype)
{
unsigned long page_idx;
+ unsigned long combined_idx;
+ struct page *buddy;
if (unlikely(PageCompound(page)))
if (unlikely(destroy_compound_page(page, order)))
@@ -488,9 +507,6 @@ static inline void __free_one_page(struct page *page,
VM_BUG_ON(bad_range(zone, page));
while (order < MAX_ORDER-1) {
- unsigned long combined_idx;
- struct page *buddy;
-
buddy = __page_find_buddy(page, page_idx, order);
if (!page_is_buddy(page, buddy, order))
break;
@@ -505,8 +521,29 @@ static inline void __free_one_page(struct page *page,
order++;
}
set_page_order(page, order);
- list_add(&page->lru,
- &zone->free_area[order].free_list[migratetype]);
+
+ /*
+ * If this is not the largest possible page, check if the buddy
+ * of the next-highest order is free. If it is, it's possible
+ * that pages are being freed that will coalesce soon. In case,
+ * that is happening, add the free page to the tail of the list
+ * so it's less likely to be used soon and more likely to be merged
+ * as a higher order page
+ */
+ if ((order < MAX_ORDER-1) && pfn_valid_within(page_to_pfn(buddy))) {
+ struct page *higher_page, *higher_buddy;
+ combined_idx = __find_combined_index(page_idx, order);
+ higher_page = page + combined_idx - page_idx;
+ higher_buddy = __page_find_buddy(higher_page, combined_idx, order + 1);
+ if (page_is_buddy(higher_page, higher_buddy, order + 1)) {
+ list_add_tail(&page->lru,
+ &zone->free_area[order].free_list[migratetype]);
+ goto out;
+ }
+ }
+
+ list_add(&page->lru, &zone->free_area[order].free_list[migratetype]);
+out:
zone->free_area[order].nr_free++;
}
@@ -599,20 +636,23 @@ static void free_one_page(struct zone *zone, struct page *page, int order,
spin_unlock(&zone->lock);
}
-static void __free_pages_ok(struct page *page, unsigned int order)
+static bool free_pages_prepare(struct page *page, unsigned int order)
{
- unsigned long flags;
int i;
int bad = 0;
- int wasMlocked = __TestClearPageMlocked(page);
trace_mm_page_free_direct(page, order);
kmemcheck_free_shadow(page, order);
- for (i = 0 ; i < (1 << order) ; ++i)
- bad += free_pages_check(page + i);
+ for (i = 0; i < (1 << order); i++) {
+ struct page *pg = page + i;
+
+ if (PageAnon(pg))
+ pg->mapping = NULL;
+ bad += free_pages_check(pg);
+ }
if (bad)
- return;
+ return false;
if (!PageHighMem(page)) {
debug_check_no_locks_freed(page_address(page),PAGE_SIZE<<order);
@@ -622,6 +662,17 @@ static void __free_pages_ok(struct page *page, unsigned int order)
arch_free_page(page, order);
kernel_map_pages(page, 1 << order, 0);
+ return true;
+}
+
+static void __free_pages_ok(struct page *page, unsigned int order)
+{
+ unsigned long flags;
+ int wasMlocked = __TestClearPageMlocked(page);
+
+ if (!free_pages_prepare(page, order))
+ return;
+
local_irq_save(flags);
if (unlikely(wasMlocked))
free_page_mlock(page);
@@ -1107,21 +1158,9 @@ void free_hot_cold_page(struct page *page, int cold)
int migratetype;
int wasMlocked = __TestClearPageMlocked(page);
- trace_mm_page_free_direct(page, 0);
- kmemcheck_free_shadow(page, 0);
-
- if (PageAnon(page))
- page->mapping = NULL;
- if (free_pages_check(page))
+ if (!free_pages_prepare(page, 0))
return;
- if (!PageHighMem(page)) {
- debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
- debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
- }
- arch_free_page(page, 0);
- kernel_map_pages(page, 1, 0);
-
migratetype = get_pageblock_migratetype(page);
set_page_private(page, migratetype);
local_irq_save(flags);
@@ -1188,6 +1227,51 @@ void split_page(struct page *page, unsigned int order)
}
/*
+ * Similar to split_page except the page is already free. As this is only
+ * being used for migration, the migratetype of the block also changes.
+ * As this is called with interrupts disabled, the caller is responsible
+ * for calling arch_alloc_page() and kernel_map_page() after interrupts
+ * are enabled.
+ *
+ * Note: this is probably too low level an operation for use in drivers.
+ * Please consult with lkml before using this in your driver.
+ */
+int split_free_page(struct page *page)
+{
+ unsigned int order;
+ unsigned long watermark;
+ struct zone *zone;
+
+ BUG_ON(!PageBuddy(page));
+
+ zone = page_zone(page);
+ order = page_order(page);
+
+ /* Obey watermarks as if the page was being allocated */
+ watermark = low_wmark_pages(zone) + (1 << order);
+ if (!zone_watermark_ok(zone, 0, watermark, 0, 0))
+ return 0;
+
+ /* Remove page from free list */
+ list_del(&page->lru);
+ zone->free_area[order].nr_free--;
+ rmv_page_order(page);
+ __mod_zone_page_state(zone, NR_FREE_PAGES, -(1UL << order));
+
+ /* Split into individual pages */
+ set_page_refcounted(page);
+ split_page(page, order);
+
+ if (order >= pageblock_order - 1) {
+ struct page *endpage = page + (1 << order) - 1;
+ for (; page < endpage; page += pageblock_nr_pages)
+ set_pageblock_migratetype(page, MIGRATE_MOVABLE);
+ }
+
+ return 1 << order;
+}
+
+/*
* Really, prep_compound_page() should be called from __rmqueue_bulk(). But
* we cheat by calling it from here, in the order > 0 path. Saves a branch
* or two.
@@ -1693,6 +1777,62 @@ out:
return page;
}
+#ifdef CONFIG_COMPACTION
+/* Try memory compaction for high-order allocations before reclaim */
+static struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+ int migratetype, unsigned long *did_some_progress)
+{
+ struct page *page;
+
+ if (!order || compaction_deferred(preferred_zone))
+ return NULL;
+
+ *did_some_progress = try_to_compact_pages(zonelist, order, gfp_mask,
+ nodemask);
+ if (*did_some_progress != COMPACT_SKIPPED) {
+
+ /* Page migration frees to the PCP lists but we want merging */
+ drain_pages(get_cpu());
+ put_cpu();
+
+ page = get_page_from_freelist(gfp_mask, nodemask,
+ order, zonelist, high_zoneidx,
+ alloc_flags, preferred_zone,
+ migratetype);
+ if (page) {
+ preferred_zone->compact_considered = 0;
+ preferred_zone->compact_defer_shift = 0;
+ count_vm_event(COMPACTSUCCESS);
+ return page;
+ }
+
+ /*
+ * It's bad if compaction run occurs and fails.
+ * The most likely reason is that pages exist,
+ * but not enough to satisfy watermarks.
+ */
+ count_vm_event(COMPACTFAIL);
+ defer_compaction(preferred_zone);
+
+ cond_resched();
+ }
+
+ return NULL;
+}
+#else
+static inline struct page *
+__alloc_pages_direct_compact(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, int alloc_flags, struct zone *preferred_zone,
+ int migratetype, unsigned long *did_some_progress)
+{
+ return NULL;
+}
+#endif /* CONFIG_COMPACTION */
+
/* The really slow allocator path where we enter direct reclaim */
static inline struct page *
__alloc_pages_direct_reclaim(gfp_t gfp_mask, unsigned int order,
@@ -1879,6 +2019,15 @@ rebalance:
if (test_thread_flag(TIF_MEMDIE) && !(gfp_mask & __GFP_NOFAIL))
goto nopage;
+ /* Try direct compaction */
+ page = __alloc_pages_direct_compact(gfp_mask, order,
+ zonelist, high_zoneidx,
+ nodemask,
+ alloc_flags, preferred_zone,
+ migratetype, &did_some_progress);
+ if (page)
+ goto got_pg;
+
/* Try direct reclaim and then allocating */
page = __alloc_pages_direct_reclaim(gfp_mask, order,
zonelist, high_zoneidx,
@@ -1970,10 +2119,13 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
if (unlikely(!zonelist->_zonerefs->zone))
return NULL;
+ get_mems_allowed();
/* The preferred zone is used for statistics later */
first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
- if (!preferred_zone)
+ if (!preferred_zone) {
+ put_mems_allowed();
return NULL;
+ }
/* First allocation attempt */
page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
@@ -1983,6 +2135,7 @@ __alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
page = __alloc_pages_slowpath(gfp_mask, order,
zonelist, high_zoneidx, nodemask,
preferred_zone, migratetype);
+ put_mems_allowed();
trace_mm_page_alloc(page, order, gfp_mask, migratetype);
return page;
@@ -2434,8 +2587,11 @@ int numa_zonelist_order_handler(ctl_table *table, int write,
strncpy((char*)table->data, saved_string,
NUMA_ZONELIST_ORDER_LEN);
user_zonelist_order = oldval;
- } else if (oldval != user_zonelist_order)
- build_all_zonelists();
+ } else if (oldval != user_zonelist_order) {
+ mutex_lock(&zonelists_mutex);
+ build_all_zonelists(NULL);
+ mutex_unlock(&zonelists_mutex);
+ }
}
out:
mutex_unlock(&zl_order_mutex);
@@ -2582,7 +2738,7 @@ static int default_zonelist_order(void)
* ZONE_DMA and ZONE_DMA32 can be very small area in the system.
* If they are really small and used heavily, the system can fall
* into OOM very easily.
- * This function detect ZONE_DMA/DMA32 size and confgigures zone order.
+ * This function detect ZONE_DMA/DMA32 size and configures zone order.
*/
/* Is there ZONE_NORMAL ? (ex. ppc has only DMA zone..) */
low_kmem_size = 0;
@@ -2594,6 +2750,15 @@ static int default_zonelist_order(void)
if (zone_type < ZONE_NORMAL)
low_kmem_size += z->present_pages;
total_size += z->present_pages;
+ } else if (zone_type == ZONE_NORMAL) {
+ /*
+ * If any node has only lowmem, then node order
+ * is preferred to allow kernel allocations
+ * locally; otherwise, they can easily infringe
+ * on other nodes when there is an abundance of
+ * lowmem available to allocate from.
+ */
+ return ZONELIST_ORDER_NODE;
}
}
}
@@ -2707,6 +2872,24 @@ static void build_zonelist_cache(pg_data_t *pgdat)
zlc->z_to_n[z - zonelist->_zonerefs] = zonelist_node_idx(z);
}
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+/*
+ * Return node id of node used for "local" allocations.
+ * I.e., first node id of first zone in arg node's generic zonelist.
+ * Used for initializing percpu 'numa_mem', which is used primarily
+ * for kernel allocations, so use GFP_KERNEL flags to locate zonelist.
+ */
+int local_memory_node(int node)
+{
+ struct zone *zone;
+
+ (void)first_zones_zonelist(node_zonelist(node, GFP_KERNEL),
+ gfp_zone(GFP_KERNEL),
+ NULL,
+ &zone);
+ return zone->node;
+}
+#endif
#else /* CONFIG_NUMA */
@@ -2776,9 +2959,16 @@ static void build_zonelist_cache(pg_data_t *pgdat)
*/
static void setup_pageset(struct per_cpu_pageset *p, unsigned long batch);
static DEFINE_PER_CPU(struct per_cpu_pageset, boot_pageset);
+static void setup_zone_pageset(struct zone *zone);
+
+/*
+ * Global mutex to protect against size modification of zonelists
+ * as well as to serialize pageset setup for the new populated zone.
+ */
+DEFINE_MUTEX(zonelists_mutex);
/* return values int ....just for stop_machine() */
-static int __build_all_zonelists(void *dummy)
+static __init_refok int __build_all_zonelists(void *data)
{
int nid;
int cpu;
@@ -2793,6 +2983,14 @@ static int __build_all_zonelists(void *dummy)
build_zonelist_cache(pgdat);
}
+#ifdef CONFIG_MEMORY_HOTPLUG
+ /* Setup real pagesets for the new zone */
+ if (data) {
+ struct zone *zone = data;
+ setup_zone_pageset(zone);
+ }
+#endif
+
/*
* Initialize the boot_pagesets that are going to be used
* for bootstrapping processors. The real pagesets for
@@ -2806,13 +3004,31 @@ static int __build_all_zonelists(void *dummy)
* needs the percpu allocator in order to allocate its pagesets
* (a chicken-egg dilemma).
*/
- for_each_possible_cpu(cpu)
+ for_each_possible_cpu(cpu) {
setup_pageset(&per_cpu(boot_pageset, cpu), 0);
+#ifdef CONFIG_HAVE_MEMORYLESS_NODES
+ /*
+ * We now know the "local memory node" for each node--
+ * i.e., the node of the first zone in the generic zonelist.
+ * Set up numa_mem percpu variable for on-line cpus. During
+ * boot, only the boot cpu should be on-line; we'll init the
+ * secondary cpus' numa_mem as they come on-line. During
+ * node/memory hotplug, we'll fixup all on-line cpus.
+ */
+ if (cpu_online(cpu))
+ set_cpu_numa_mem(cpu, local_memory_node(cpu_to_node(cpu)));
+#endif
+ }
+
return 0;
}
-void build_all_zonelists(void)
+/*
+ * Called with zonelists_mutex held always
+ * unless system_state == SYSTEM_BOOTING.
+ */
+void build_all_zonelists(void *data)
{
set_zonelist_order();
@@ -2823,7 +3039,7 @@ void build_all_zonelists(void)
} else {
/* we have to stop all cpus to guarantee there is no user
of zonelist */
- stop_machine(__build_all_zonelists, NULL, NULL);
+ stop_machine(__build_all_zonelists, data, NULL);
/* cpuset refresh routine should be here */
}
vm_total_pages = nr_free_pagecache_pages();
@@ -3146,31 +3362,34 @@ static void setup_pagelist_highmark(struct per_cpu_pageset *p,
pcp->batch = PAGE_SHIFT * 8;
}
+static __meminit void setup_zone_pageset(struct zone *zone)
+{
+ int cpu;
+
+ zone->pageset = alloc_percpu(struct per_cpu_pageset);
+
+ for_each_possible_cpu(cpu) {
+ struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
+
+ setup_pageset(pcp, zone_batchsize(zone));
+
+ if (percpu_pagelist_fraction)
+ setup_pagelist_highmark(pcp,
+ (zone->present_pages /
+ percpu_pagelist_fraction));
+ }
+}
+
/*
* Allocate per cpu pagesets and initialize them.
* Before this call only boot pagesets were available.
- * Boot pagesets will no longer be used by this processorr
- * after setup_per_cpu_pageset().
*/
void __init setup_per_cpu_pageset(void)
{
struct zone *zone;
- int cpu;
-
- for_each_populated_zone(zone) {
- zone->pageset = alloc_percpu(struct per_cpu_pageset);
-
- for_each_possible_cpu(cpu) {
- struct per_cpu_pageset *pcp = per_cpu_ptr(zone->pageset, cpu);
-
- setup_pageset(pcp, zone_batchsize(zone));
- if (percpu_pagelist_fraction)
- setup_pagelist_highmark(pcp,
- (zone->present_pages /
- percpu_pagelist_fraction));
- }
- }
+ for_each_populated_zone(zone)
+ setup_zone_pageset(zone);
}
static noinline __init_refok
diff --git a/mm/readahead.c b/mm/readahead.c
index dfa9a1a03a1..77506a291a2 100644
--- a/mm/readahead.c
+++ b/mm/readahead.c
@@ -523,7 +523,7 @@ EXPORT_SYMBOL_GPL(page_cache_sync_readahead);
* @req_size: hint: total size of the read which the caller is performing in
* pagecache pages
*
- * page_cache_async_ondemand() should be called when a page is used which
+ * page_cache_async_readahead() should be called when a page is used which
* has the PG_readahead flag; this is a marker to suggest that the application
* has used up enough of the readahead window that we should start pulling in
* more pages.
diff --git a/mm/rmap.c b/mm/rmap.c
index 0feeef860a8..38a336e2eea 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -250,7 +250,7 @@ static void anon_vma_unlink(struct anon_vma_chain *anon_vma_chain)
list_del(&anon_vma_chain->same_anon_vma);
/* We must garbage collect the anon_vma if it's empty */
- empty = list_empty(&anon_vma->head) && !ksm_refcount(anon_vma);
+ empty = list_empty(&anon_vma->head) && !anonvma_external_refcount(anon_vma);
spin_unlock(&anon_vma->lock);
if (empty)
@@ -274,7 +274,7 @@ static void anon_vma_ctor(void *data)
struct anon_vma *anon_vma = data;
spin_lock_init(&anon_vma->lock);
- ksm_refcount_init(anon_vma);
+ anonvma_external_refcount_init(anon_vma);
INIT_LIST_HEAD(&anon_vma->head);
}
@@ -1131,6 +1131,20 @@ static int try_to_unmap_cluster(unsigned long cursor, unsigned int *mapcount,
return ret;
}
+static bool is_vma_temporary_stack(struct vm_area_struct *vma)
+{
+ int maybe_stack = vma->vm_flags & (VM_GROWSDOWN | VM_GROWSUP);
+
+ if (!maybe_stack)
+ return false;
+
+ if ((vma->vm_flags & VM_STACK_INCOMPLETE_SETUP) ==
+ VM_STACK_INCOMPLETE_SETUP)
+ return true;
+
+ return false;
+}
+
/**
* try_to_unmap_anon - unmap or unlock anonymous page using the object-based
* rmap method
@@ -1159,7 +1173,21 @@ static int try_to_unmap_anon(struct page *page, enum ttu_flags flags)
list_for_each_entry(avc, &anon_vma->head, same_anon_vma) {
struct vm_area_struct *vma = avc->vma;
- unsigned long address = vma_address(page, vma);
+ unsigned long address;
+
+ /*
+ * During exec, a temporary VMA is setup and later moved.
+ * The VMA is moved under the anon_vma lock but not the
+ * page tables leading to a race where migration cannot
+ * find the migration ptes. Rather than increasing the
+ * locking requirements of exec(), migration skips
+ * temporary VMAs until after exec() completes.
+ */
+ if (PAGE_MIGRATION && (flags & TTU_MIGRATION) &&
+ is_vma_temporary_stack(vma))
+ continue;
+
+ address = vma_address(page, vma);
if (address == -EFAULT)
continue;
ret = try_to_unmap_one(page, vma, address, flags);
@@ -1355,10 +1383,8 @@ static int rmap_walk_anon(struct page *page, int (*rmap_one)(struct page *,
/*
* Note: remove_migration_ptes() cannot use page_lock_anon_vma()
* because that depends on page_mapped(); but not all its usages
- * are holding mmap_sem, which also gave the necessary guarantee
- * (that this anon_vma's slab has not already been destroyed).
- * This needs to be reviewed later: avoiding page_lock_anon_vma()
- * is risky, and currently limits the usefulness of rmap_walk().
+ * are holding mmap_sem. Users without mmap_sem are required to
+ * take a reference count to prevent the anon_vma disappearing
*/
anon_vma = page_anon_vma(page);
if (!anon_vma)
diff --git a/mm/shmem.c b/mm/shmem.c
index 0cd7f66f1c6..7e5030ae18f 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -433,8 +433,6 @@ static swp_entry_t *shmem_swp_alloc(struct shmem_inode_info *info, unsigned long
spin_unlock(&info->lock);
page = shmem_dir_alloc(mapping_gfp_mask(inode->i_mapping));
- if (page)
- set_page_private(page, 0);
spin_lock(&info->lock);
if (!page) {
@@ -729,10 +727,11 @@ done2:
if (inode->i_mapping->nrpages && (info->flags & SHMEM_PAGEIN)) {
/*
* Call truncate_inode_pages again: racing shmem_unuse_inode
- * may have swizzled a page in from swap since vmtruncate or
- * generic_delete_inode did it, before we lowered next_index.
- * Also, though shmem_getpage checks i_size before adding to
- * cache, no recheck after: so fix the narrow window there too.
+ * may have swizzled a page in from swap since
+ * truncate_pagecache or generic_delete_inode did it, before we
+ * lowered next_index. Also, though shmem_getpage checks
+ * i_size before adding to cache, no recheck after: so fix the
+ * narrow window there too.
*
* Recalling truncate_inode_pages_range and unmap_mapping_range
* every time for punch_hole (which never got a chance to clear
@@ -762,19 +761,16 @@ done2:
}
}
-static void shmem_truncate(struct inode *inode)
-{
- shmem_truncate_range(inode, inode->i_size, (loff_t)-1);
-}
-
static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
{
struct inode *inode = dentry->d_inode;
- struct page *page = NULL;
int error;
if (S_ISREG(inode->i_mode) && (attr->ia_valid & ATTR_SIZE)) {
- if (attr->ia_size < inode->i_size) {
+ loff_t newsize = attr->ia_size;
+ struct page *page = NULL;
+
+ if (newsize < inode->i_size) {
/*
* If truncating down to a partial page, then
* if that page is already allocated, hold it
@@ -782,9 +778,9 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
* truncate_partial_page cannnot miss it were
* it assigned to swap.
*/
- if (attr->ia_size & (PAGE_CACHE_SIZE-1)) {
+ if (newsize & (PAGE_CACHE_SIZE-1)) {
(void) shmem_getpage(inode,
- attr->ia_size>>PAGE_CACHE_SHIFT,
+ newsize >> PAGE_CACHE_SHIFT,
&page, SGP_READ, NULL);
if (page)
unlock_page(page);
@@ -796,24 +792,29 @@ static int shmem_notify_change(struct dentry *dentry, struct iattr *attr)
* if it's being fully truncated to zero-length: the
* nrpages check is efficient enough in that case.
*/
- if (attr->ia_size) {
+ if (newsize) {
struct shmem_inode_info *info = SHMEM_I(inode);
spin_lock(&info->lock);
info->flags &= ~SHMEM_PAGEIN;
spin_unlock(&info->lock);
}
}
+
+ error = simple_setsize(inode, newsize);
+ if (page)
+ page_cache_release(page);
+ if (error)
+ return error;
+ shmem_truncate_range(inode, newsize, (loff_t)-1);
}
error = inode_change_ok(inode, attr);
if (!error)
- error = inode_setattr(inode, attr);
+ generic_setattr(inode, attr);
#ifdef CONFIG_TMPFS_POSIX_ACL
if (!error && (attr->ia_valid & ATTR_MODE))
error = generic_acl_chmod(inode);
#endif
- if (page)
- page_cache_release(page);
return error;
}
@@ -821,11 +822,11 @@ static void shmem_delete_inode(struct inode *inode)
{
struct shmem_inode_info *info = SHMEM_I(inode);
- if (inode->i_op->truncate == shmem_truncate) {
+ if (inode->i_mapping->a_ops == &shmem_aops) {
truncate_inode_pages(inode->i_mapping, 0);
shmem_unacct_size(info->flags, inode->i_size);
inode->i_size = 0;
- shmem_truncate(inode);
+ shmem_truncate_range(inode, 0, (loff_t)-1);
if (!list_empty(&info->swaplist)) {
mutex_lock(&shmem_swaplist_mutex);
list_del_init(&info->swaplist);
@@ -2024,7 +2025,6 @@ static const struct inode_operations shmem_symlink_inline_operations = {
};
static const struct inode_operations shmem_symlink_inode_operations = {
- .truncate = shmem_truncate,
.readlink = generic_readlink,
.follow_link = shmem_follow_link,
.put_link = shmem_put_link,
@@ -2435,14 +2435,13 @@ static const struct file_operations shmem_file_operations = {
.write = do_sync_write,
.aio_read = shmem_file_aio_read,
.aio_write = generic_file_aio_write,
- .fsync = simple_sync_file,
+ .fsync = noop_fsync,
.splice_read = generic_file_splice_read,
.splice_write = generic_file_splice_write,
#endif
};
static const struct inode_operations shmem_inode_operations = {
- .truncate = shmem_truncate,
.setattr = shmem_notify_change,
.truncate_range = shmem_truncate_range,
#ifdef CONFIG_TMPFS_POSIX_ACL
@@ -2561,6 +2560,45 @@ out4:
return error;
}
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR
+/**
+ * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file
+ * @inode: the inode to be searched
+ * @pgoff: the offset to be searched
+ * @pagep: the pointer for the found page to be stored
+ * @ent: the pointer for the found swap entry to be stored
+ *
+ * If a page is found, refcount of it is incremented. Callers should handle
+ * these refcount.
+ */
+void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
+ struct page **pagep, swp_entry_t *ent)
+{
+ swp_entry_t entry = { .val = 0 }, *ptr;
+ struct page *page = NULL;
+ struct shmem_inode_info *info = SHMEM_I(inode);
+
+ if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode))
+ goto out;
+
+ spin_lock(&info->lock);
+ ptr = shmem_swp_entry(info, pgoff, NULL);
+#ifdef CONFIG_SWAP
+ if (ptr && ptr->val) {
+ entry.val = ptr->val;
+ page = find_get_page(&swapper_space, entry.val);
+ } else
+#endif
+ page = find_get_page(inode->i_mapping, pgoff);
+ if (ptr)
+ shmem_swp_unmap(ptr);
+ spin_unlock(&info->lock);
+out:
+ *pagep = page;
+ *ent = entry;
+}
+#endif
+
#else /* !CONFIG_SHMEM */
/*
@@ -2600,6 +2638,31 @@ int shmem_lock(struct file *file, int lock, struct user_struct *user)
return 0;
}
+#ifdef CONFIG_CGROUP_MEM_RES_CTLR
+/**
+ * mem_cgroup_get_shmem_target - find a page or entry assigned to the shmem file
+ * @inode: the inode to be searched
+ * @pgoff: the offset to be searched
+ * @pagep: the pointer for the found page to be stored
+ * @ent: the pointer for the found swap entry to be stored
+ *
+ * If a page is found, refcount of it is incremented. Callers should handle
+ * these refcount.
+ */
+void mem_cgroup_get_shmem_target(struct inode *inode, pgoff_t pgoff,
+ struct page **pagep, swp_entry_t *ent)
+{
+ struct page *page = NULL;
+
+ if ((pgoff << PAGE_CACHE_SHIFT) >= i_size_read(inode))
+ goto out;
+ page = find_get_page(inode->i_mapping, pgoff);
+out:
+ *pagep = page;
+ *ent = (swp_entry_t){ .val = 0 };
+}
+#endif
+
#define shmem_vm_ops generic_file_vm_ops
#define shmem_file_operations ramfs_file_operations
#define shmem_get_inode(sb, dir, mode, dev, flags) ramfs_get_inode(sb, dir, mode, dev)
diff --git a/mm/slab.c b/mm/slab.c
index bac0f4fcc21..e49f8f46f46 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -115,6 +115,7 @@
#include <linux/reciprocal_div.h>
#include <linux/debugobjects.h>
#include <linux/kmemcheck.h>
+#include <linux/memory.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
@@ -144,30 +145,6 @@
#define BYTES_PER_WORD sizeof(void *)
#define REDZONE_ALIGN max(BYTES_PER_WORD, __alignof__(unsigned long long))
-#ifndef ARCH_KMALLOC_MINALIGN
-/*
- * Enforce a minimum alignment for the kmalloc caches.
- * Usually, the kmalloc caches are cache_line_size() aligned, except when
- * DEBUG and FORCED_DEBUG are enabled, then they are BYTES_PER_WORD aligned.
- * Some archs want to perform DMA into kmalloc caches and need a guaranteed
- * alignment larger than the alignment of a 64-bit integer.
- * ARCH_KMALLOC_MINALIGN allows that.
- * Note that increasing this value may disable some debug features.
- */
-#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
-#endif
-
-#ifndef ARCH_SLAB_MINALIGN
-/*
- * Enforce a minimum alignment for all caches.
- * Intended for archs that get misalignment faults even for BYTES_PER_WORD
- * aligned buffers. Includes ARCH_KMALLOC_MINALIGN.
- * If possible: Do not enable this flag for CONFIG_DEBUG_SLAB, it disables
- * some debug features.
- */
-#define ARCH_SLAB_MINALIGN 0
-#endif
-
#ifndef ARCH_KMALLOC_FLAGS
#define ARCH_KMALLOC_FLAGS SLAB_HWCACHE_ALIGN
#endif
@@ -844,7 +821,7 @@ static void init_reap_node(int cpu)
{
int node;
- node = next_node(cpu_to_node(cpu), node_online_map);
+ node = next_node(cpu_to_mem(cpu), node_online_map);
if (node == MAX_NUMNODES)
node = first_node(node_online_map);
@@ -1073,7 +1050,7 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
struct array_cache *alien = NULL;
int node;
- node = numa_node_id();
+ node = numa_mem_id();
/*
* Make sure we are not freeing a object from another node to the array
@@ -1102,11 +1079,57 @@ static inline int cache_free_alien(struct kmem_cache *cachep, void *objp)
}
#endif
+/*
+ * Allocates and initializes nodelists for a node on each slab cache, used for
+ * either memory or cpu hotplug. If memory is being hot-added, the kmem_list3
+ * will be allocated off-node since memory is not yet online for the new node.
+ * When hotplugging memory or a cpu, existing nodelists are not replaced if
+ * already in use.
+ *
+ * Must hold cache_chain_mutex.
+ */
+static int init_cache_nodelists_node(int node)
+{
+ struct kmem_cache *cachep;
+ struct kmem_list3 *l3;
+ const int memsize = sizeof(struct kmem_list3);
+
+ list_for_each_entry(cachep, &cache_chain, next) {
+ /*
+ * Set up the size64 kmemlist for cpu before we can
+ * begin anything. Make sure some other cpu on this
+ * node has not already allocated this
+ */
+ if (!cachep->nodelists[node]) {
+ l3 = kmalloc_node(memsize, GFP_KERNEL, node);
+ if (!l3)
+ return -ENOMEM;
+ kmem_list3_init(l3);
+ l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
+ ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
+
+ /*
+ * The l3s don't come and go as CPUs come and
+ * go. cache_chain_mutex is sufficient
+ * protection here.
+ */
+ cachep->nodelists[node] = l3;
+ }
+
+ spin_lock_irq(&cachep->nodelists[node]->list_lock);
+ cachep->nodelists[node]->free_limit =
+ (1 + nr_cpus_node(node)) *
+ cachep->batchcount + cachep->num;
+ spin_unlock_irq(&cachep->nodelists[node]->list_lock);
+ }
+ return 0;
+}
+
static void __cpuinit cpuup_canceled(long cpu)
{
struct kmem_cache *cachep;
struct kmem_list3 *l3 = NULL;
- int node = cpu_to_node(cpu);
+ int node = cpu_to_mem(cpu);
const struct cpumask *mask = cpumask_of_node(node);
list_for_each_entry(cachep, &cache_chain, next) {
@@ -1171,8 +1194,8 @@ static int __cpuinit cpuup_prepare(long cpu)
{
struct kmem_cache *cachep;
struct kmem_list3 *l3 = NULL;
- int node = cpu_to_node(cpu);
- const int memsize = sizeof(struct kmem_list3);
+ int node = cpu_to_mem(cpu);
+ int err;
/*
* We need to do this right in the beginning since
@@ -1180,35 +1203,9 @@ static int __cpuinit cpuup_prepare(long cpu)
* kmalloc_node allows us to add the slab to the right
* kmem_list3 and not this cpu's kmem_list3
*/
-
- list_for_each_entry(cachep, &cache_chain, next) {
- /*
- * Set up the size64 kmemlist for cpu before we can
- * begin anything. Make sure some other cpu on this
- * node has not already allocated this
- */
- if (!cachep->nodelists[node]) {
- l3 = kmalloc_node(memsize, GFP_KERNEL, node);
- if (!l3)
- goto bad;
- kmem_list3_init(l3);
- l3->next_reap = jiffies + REAPTIMEOUT_LIST3 +
- ((unsigned long)cachep) % REAPTIMEOUT_LIST3;
-
- /*
- * The l3s don't come and go as CPUs come and
- * go. cache_chain_mutex is sufficient
- * protection here.
- */
- cachep->nodelists[node] = l3;
- }
-
- spin_lock_irq(&cachep->nodelists[node]->list_lock);
- cachep->nodelists[node]->free_limit =
- (1 + nr_cpus_node(node)) *
- cachep->batchcount + cachep->num;
- spin_unlock_irq(&cachep->nodelists[node]->list_lock);
- }
+ err = init_cache_nodelists_node(node);
+ if (err < 0)
+ goto bad;
/*
* Now we can go ahead with allocating the shared arrays and
@@ -1324,18 +1321,82 @@ static int __cpuinit cpuup_callback(struct notifier_block *nfb,
mutex_unlock(&cache_chain_mutex);
break;
}
- return err ? NOTIFY_BAD : NOTIFY_OK;
+ return notifier_from_errno(err);
}
static struct notifier_block __cpuinitdata cpucache_notifier = {
&cpuup_callback, NULL, 0
};
+#if defined(CONFIG_NUMA) && defined(CONFIG_MEMORY_HOTPLUG)
+/*
+ * Drains freelist for a node on each slab cache, used for memory hot-remove.
+ * Returns -EBUSY if all objects cannot be drained so that the node is not
+ * removed.
+ *
+ * Must hold cache_chain_mutex.
+ */
+static int __meminit drain_cache_nodelists_node(int node)
+{
+ struct kmem_cache *cachep;
+ int ret = 0;
+
+ list_for_each_entry(cachep, &cache_chain, next) {
+ struct kmem_list3 *l3;
+
+ l3 = cachep->nodelists[node];
+ if (!l3)
+ continue;
+
+ drain_freelist(cachep, l3, l3->free_objects);
+
+ if (!list_empty(&l3->slabs_full) ||
+ !list_empty(&l3->slabs_partial)) {
+ ret = -EBUSY;
+ break;
+ }
+ }
+ return ret;
+}
+
+static int __meminit slab_memory_callback(struct notifier_block *self,
+ unsigned long action, void *arg)
+{
+ struct memory_notify *mnb = arg;
+ int ret = 0;
+ int nid;
+
+ nid = mnb->status_change_nid;
+ if (nid < 0)
+ goto out;
+
+ switch (action) {
+ case MEM_GOING_ONLINE:
+ mutex_lock(&cache_chain_mutex);
+ ret = init_cache_nodelists_node(nid);
+ mutex_unlock(&cache_chain_mutex);
+ break;
+ case MEM_GOING_OFFLINE:
+ mutex_lock(&cache_chain_mutex);
+ ret = drain_cache_nodelists_node(nid);
+ mutex_unlock(&cache_chain_mutex);
+ break;
+ case MEM_ONLINE:
+ case MEM_OFFLINE:
+ case MEM_CANCEL_ONLINE:
+ case MEM_CANCEL_OFFLINE:
+ break;
+ }
+out:
+ return ret ? notifier_from_errno(ret) : NOTIFY_OK;
+}
+#endif /* CONFIG_NUMA && CONFIG_MEMORY_HOTPLUG */
+
/*
* swap the static kmem_list3 with kmalloced memory
*/
-static void init_list(struct kmem_cache *cachep, struct kmem_list3 *list,
- int nodeid)
+static void __init init_list(struct kmem_cache *cachep, struct kmem_list3 *list,
+ int nodeid)
{
struct kmem_list3 *ptr;
@@ -1418,7 +1479,7 @@ void __init kmem_cache_init(void)
* 6) Resize the head arrays of the kmalloc caches to their final sizes.
*/
- node = numa_node_id();
+ node = numa_mem_id();
/* 1) create the cache_cache */
INIT_LIST_HEAD(&cache_chain);
@@ -1580,6 +1641,14 @@ void __init kmem_cache_init_late(void)
*/
register_cpu_notifier(&cpucache_notifier);
+#ifdef CONFIG_NUMA
+ /*
+ * Register a memory hotplug callback that initializes and frees
+ * nodelists.
+ */
+ hotplug_memory_notifier(slab_memory_callback, SLAB_CALLBACK_PRI);
+#endif
+
/*
* The reap timers are started later, with a module init call: That part
* of the kernel is not yet operational.
@@ -2052,7 +2121,7 @@ static int __init_refok setup_cpu_cache(struct kmem_cache *cachep, gfp_t gfp)
}
}
}
- cachep->nodelists[numa_node_id()]->next_reap =
+ cachep->nodelists[numa_mem_id()]->next_reap =
jiffies + REAPTIMEOUT_LIST3 +
((unsigned long)cachep) % REAPTIMEOUT_LIST3;
@@ -2220,8 +2289,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
if (ralign < align) {
ralign = align;
}
- /* disable debug if necessary */
- if (ralign > __alignof__(unsigned long long))
+ /* disable debug if not aligning with REDZONE_ALIGN */
+ if (ralign & (__alignof__(unsigned long long) - 1))
flags &= ~(SLAB_RED_ZONE | SLAB_STORE_USER);
/*
* 4) Store it.
@@ -2247,8 +2316,8 @@ kmem_cache_create (const char *name, size_t size, size_t align,
*/
if (flags & SLAB_RED_ZONE) {
/* add space for red zone words */
- cachep->obj_offset += sizeof(unsigned long long);
- size += 2 * sizeof(unsigned long long);
+ cachep->obj_offset += align;
+ size += align + sizeof(unsigned long long);
}
if (flags & SLAB_STORE_USER) {
/* user store requires one word storage behind the end of
@@ -2383,7 +2452,7 @@ static void check_spinlock_acquired(struct kmem_cache *cachep)
{
#ifdef CONFIG_SMP
check_irq_off();
- assert_spin_locked(&cachep->nodelists[numa_node_id()]->list_lock);
+ assert_spin_locked(&cachep->nodelists[numa_mem_id()]->list_lock);
#endif
}
@@ -2410,7 +2479,7 @@ static void do_drain(void *arg)
{
struct kmem_cache *cachep = arg;
struct array_cache *ac;
- int node = numa_node_id();
+ int node = numa_mem_id();
check_irq_off();
ac = cpu_cache_get(cachep);
@@ -2943,7 +3012,7 @@ static void *cache_alloc_refill(struct kmem_cache *cachep, gfp_t flags)
retry:
check_irq_off();
- node = numa_node_id();
+ node = numa_mem_id();
ac = cpu_cache_get(cachep);
batchcount = ac->batchcount;
if (!ac->touched && batchcount > BATCHREFILL_LIMIT) {
@@ -3147,11 +3216,13 @@ static void *alternate_node_alloc(struct kmem_cache *cachep, gfp_t flags)
if (in_interrupt() || (flags & __GFP_THISNODE))
return NULL;
- nid_alloc = nid_here = numa_node_id();
+ nid_alloc = nid_here = numa_mem_id();
+ get_mems_allowed();
if (cpuset_do_slab_mem_spread() && (cachep->flags & SLAB_MEM_SPREAD))
- nid_alloc = cpuset_mem_spread_node();
+ nid_alloc = cpuset_slab_spread_node();
else if (current->mempolicy)
nid_alloc = slab_node(current->mempolicy);
+ put_mems_allowed();
if (nid_alloc != nid_here)
return ____cache_alloc_node(cachep, flags, nid_alloc);
return NULL;
@@ -3178,6 +3249,7 @@ static void *fallback_alloc(struct kmem_cache *cache, gfp_t flags)
if (flags & __GFP_THISNODE)
return NULL;
+ get_mems_allowed();
zonelist = node_zonelist(slab_node(current->mempolicy), flags);
local_flags = flags & (GFP_CONSTRAINT_MASK|GFP_RECLAIM_MASK);
@@ -3209,7 +3281,7 @@ retry:
if (local_flags & __GFP_WAIT)
local_irq_enable();
kmem_flagcheck(cache, flags);
- obj = kmem_getpages(cache, local_flags, numa_node_id());
+ obj = kmem_getpages(cache, local_flags, numa_mem_id());
if (local_flags & __GFP_WAIT)
local_irq_disable();
if (obj) {
@@ -3233,6 +3305,7 @@ retry:
}
}
}
+ put_mems_allowed();
return obj;
}
@@ -3316,6 +3389,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
{
unsigned long save_flags;
void *ptr;
+ int slab_node = numa_mem_id();
flags &= gfp_allowed_mask;
@@ -3328,7 +3402,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
local_irq_save(save_flags);
if (nodeid == -1)
- nodeid = numa_node_id();
+ nodeid = slab_node;
if (unlikely(!cachep->nodelists[nodeid])) {
/* Node not bootstrapped yet */
@@ -3336,7 +3410,7 @@ __cache_alloc_node(struct kmem_cache *cachep, gfp_t flags, int nodeid,
goto out;
}
- if (nodeid == numa_node_id()) {
+ if (nodeid == slab_node) {
/*
* Use the locally cached objects if possible.
* However ____cache_alloc does not allow fallback
@@ -3380,8 +3454,8 @@ __do_cache_alloc(struct kmem_cache *cache, gfp_t flags)
* We may just have run out of memory on the local node.
* ____cache_alloc_node() knows how to locate memory on other nodes
*/
- if (!objp)
- objp = ____cache_alloc_node(cache, flags, numa_node_id());
+ if (!objp)
+ objp = ____cache_alloc_node(cache, flags, numa_mem_id());
out:
return objp;
@@ -3478,7 +3552,7 @@ static void cache_flusharray(struct kmem_cache *cachep, struct array_cache *ac)
{
int batchcount;
struct kmem_list3 *l3;
- int node = numa_node_id();
+ int node = numa_mem_id();
batchcount = ac->batchcount;
#if DEBUG
@@ -3912,7 +3986,7 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
return -ENOMEM;
for_each_online_cpu(i) {
- new->new[i] = alloc_arraycache(cpu_to_node(i), limit,
+ new->new[i] = alloc_arraycache(cpu_to_mem(i), limit,
batchcount, gfp);
if (!new->new[i]) {
for (i--; i >= 0; i--)
@@ -3934,9 +4008,9 @@ static int do_tune_cpucache(struct kmem_cache *cachep, int limit,
struct array_cache *ccold = new->new[i];
if (!ccold)
continue;
- spin_lock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock);
- free_block(cachep, ccold->entry, ccold->avail, cpu_to_node(i));
- spin_unlock_irq(&cachep->nodelists[cpu_to_node(i)]->list_lock);
+ spin_lock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock);
+ free_block(cachep, ccold->entry, ccold->avail, cpu_to_mem(i));
+ spin_unlock_irq(&cachep->nodelists[cpu_to_mem(i)]->list_lock);
kfree(ccold);
}
kfree(new);
@@ -4042,7 +4116,7 @@ static void cache_reap(struct work_struct *w)
{
struct kmem_cache *searchp;
struct kmem_list3 *l3;
- int node = numa_node_id();
+ int node = numa_mem_id();
struct delayed_work *work = to_delayed_work(w);
if (!mutex_trylock(&cache_chain_mutex))
@@ -4216,10 +4290,11 @@ static int s_show(struct seq_file *m, void *p)
unsigned long node_frees = cachep->node_frees;
unsigned long overflows = cachep->node_overflow;
- seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu \
- %4lu %4lu %4lu %4lu %4lu", allocs, high, grown,
- reaped, errors, max_freeable, node_allocs,
- node_frees, overflows);
+ seq_printf(m, " : globalstat %7lu %6lu %5lu %4lu "
+ "%4lu %4lu %4lu %4lu %4lu",
+ allocs, high, grown,
+ reaped, errors, max_freeable, node_allocs,
+ node_frees, overflows);
}
/* cpu stats */
{
diff --git a/mm/slob.c b/mm/slob.c
index 837ebd64cc3..23631e2bb57 100644
--- a/mm/slob.c
+++ b/mm/slob.c
@@ -467,14 +467,6 @@ out:
* End of slob allocator proper. Begin kmem_cache_alloc and kmalloc frontend.
*/
-#ifndef ARCH_KMALLOC_MINALIGN
-#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long)
-#endif
-
-#ifndef ARCH_SLAB_MINALIGN
-#define ARCH_SLAB_MINALIGN __alignof__(unsigned long)
-#endif
-
void *__kmalloc_node(size_t size, gfp_t gfp, int node)
{
unsigned int *m;
diff --git a/mm/slub.c b/mm/slub.c
index d2a54fe71ea..578f68f3c51 100644
--- a/mm/slub.c
+++ b/mm/slub.c
@@ -157,14 +157,6 @@
#define SLUB_MERGE_SAME (SLAB_DEBUG_FREE | SLAB_RECLAIM_ACCOUNT | \
SLAB_CACHE_DMA | SLAB_NOTRACK)
-#ifndef ARCH_KMALLOC_MINALIGN
-#define ARCH_KMALLOC_MINALIGN __alignof__(unsigned long long)
-#endif
-
-#ifndef ARCH_SLAB_MINALIGN
-#define ARCH_SLAB_MINALIGN __alignof__(unsigned long long)
-#endif
-
#define OO_SHIFT 16
#define OO_MASK ((1 << OO_SHIFT) - 1)
#define MAX_OBJS_PER_PAGE 65535 /* since page.objects is u16 */
@@ -1084,7 +1076,7 @@ static inline struct page *alloc_slab_page(gfp_t flags, int node,
if (node == -1)
return alloc_pages(flags, order);
else
- return alloc_pages_node(node, flags, order);
+ return alloc_pages_exact_node(node, flags, order);
}
static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node)
@@ -1368,6 +1360,7 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
get_cycles() % 1024 > s->remote_node_defrag_ratio)
return NULL;
+ get_mems_allowed();
zonelist = node_zonelist(slab_node(current->mempolicy), flags);
for_each_zone_zonelist(zone, z, zonelist, high_zoneidx) {
struct kmem_cache_node *n;
@@ -1377,10 +1370,13 @@ static struct page *get_any_partial(struct kmem_cache *s, gfp_t flags)
if (n && cpuset_zone_allowed_hardwall(zone, flags) &&
n->nr_partial > s->min_partial) {
page = get_partial_node(n);
- if (page)
+ if (page) {
+ put_mems_allowed();
return page;
+ }
}
}
+ put_mems_allowed();
#endif
return NULL;
}
@@ -2141,7 +2137,7 @@ static void free_kmem_cache_nodes(struct kmem_cache *s)
for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n = s->node[node];
- if (n && n != &s->local_node)
+ if (n)
kmem_cache_free(kmalloc_caches, n);
s->node[node] = NULL;
}
@@ -2150,33 +2146,22 @@ static void free_kmem_cache_nodes(struct kmem_cache *s)
static int init_kmem_cache_nodes(struct kmem_cache *s, gfp_t gfpflags)
{
int node;
- int local_node;
-
- if (slab_state >= UP && (s < kmalloc_caches ||
- s >= kmalloc_caches + KMALLOC_CACHES))
- local_node = page_to_nid(virt_to_page(s));
- else
- local_node = 0;
for_each_node_state(node, N_NORMAL_MEMORY) {
struct kmem_cache_node *n;
- if (local_node == node)
- n = &s->local_node;
- else {
- if (slab_state == DOWN) {
- early_kmem_cache_node_alloc(gfpflags, node);
- continue;
- }
- n = kmem_cache_alloc_node(kmalloc_caches,
- gfpflags, node);
-
- if (!n) {
- free_kmem_cache_nodes(s);
- return 0;
- }
+ if (slab_state == DOWN) {
+ early_kmem_cache_node_alloc(gfpflags, node);
+ continue;
+ }
+ n = kmem_cache_alloc_node(kmalloc_caches,
+ gfpflags, node);
+ if (!n) {
+ free_kmem_cache_nodes(s);
+ return 0;
}
+
s->node[node] = n;
init_kmem_cache_node(n, s);
}
@@ -2429,9 +2414,11 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
#ifdef CONFIG_SLUB_DEBUG
void *addr = page_address(page);
void *p;
- DECLARE_BITMAP(map, page->objects);
+ long *map = kzalloc(BITS_TO_LONGS(page->objects) * sizeof(long),
+ GFP_ATOMIC);
- bitmap_zero(map, page->objects);
+ if (!map)
+ return;
slab_err(s, page, "%s", text);
slab_lock(page);
for_each_free_object(p, s, page->freelist)
@@ -2446,6 +2433,7 @@ static void list_slab_objects(struct kmem_cache *s, struct page *page,
}
}
slab_unlock(page);
+ kfree(map);
#endif
}
@@ -3338,8 +3326,15 @@ void *__kmalloc_node_track_caller(size_t size, gfp_t gfpflags,
struct kmem_cache *s;
void *ret;
- if (unlikely(size > SLUB_MAX_SIZE))
- return kmalloc_large_node(size, gfpflags, node);
+ if (unlikely(size > SLUB_MAX_SIZE)) {
+ ret = kmalloc_large_node(size, gfpflags, node);
+
+ trace_kmalloc_node(caller, ret,
+ size, PAGE_SIZE << get_order(size),
+ gfpflags, node);
+
+ return ret;
+ }
s = get_slab(size, gfpflags);
@@ -3651,10 +3646,10 @@ static int add_location(struct loc_track *t, struct kmem_cache *s,
}
static void process_slab(struct loc_track *t, struct kmem_cache *s,
- struct page *page, enum track_item alloc)
+ struct page *page, enum track_item alloc,
+ long *map)
{
void *addr = page_address(page);
- DECLARE_BITMAP(map, page->objects);
void *p;
bitmap_zero(map, page->objects);
@@ -3673,11 +3668,14 @@ static int list_locations(struct kmem_cache *s, char *buf,
unsigned long i;
struct loc_track t = { 0, 0, NULL };
int node;
+ unsigned long *map = kmalloc(BITS_TO_LONGS(oo_objects(s->max)) *
+ sizeof(unsigned long), GFP_KERNEL);
- if (!alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
- GFP_TEMPORARY))
+ if (!map || !alloc_loc_track(&t, PAGE_SIZE / sizeof(struct location),
+ GFP_TEMPORARY)) {
+ kfree(map);
return sprintf(buf, "Out of memory\n");
-
+ }
/* Push back cpu slabs */
flush_all(s);
@@ -3691,9 +3689,9 @@ static int list_locations(struct kmem_cache *s, char *buf,
spin_lock_irqsave(&n->list_lock, flags);
list_for_each_entry(page, &n->partial, lru)
- process_slab(&t, s, page, alloc);
+ process_slab(&t, s, page, alloc, map);
list_for_each_entry(page, &n->full, lru)
- process_slab(&t, s, page, alloc);
+ process_slab(&t, s, page, alloc, map);
spin_unlock_irqrestore(&n->list_lock, flags);
}
@@ -3744,6 +3742,7 @@ static int list_locations(struct kmem_cache *s, char *buf,
}
free_loc_track(&t);
+ kfree(map);
if (!t.count)
len += sprintf(buf, "No data\n");
return len;
diff --git a/mm/sparse.c b/mm/sparse.c
index dc0cc4d43ff..95ac219af37 100644
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -382,13 +382,15 @@ static void __init sparse_early_usemaps_alloc_node(unsigned long**usemap_map,
struct page __init *sparse_mem_map_populate(unsigned long pnum, int nid)
{
struct page *map;
+ unsigned long size;
map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
if (map)
return map;
- map = alloc_bootmem_pages_node(NODE_DATA(nid),
- PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION));
+ size = PAGE_ALIGN(sizeof(struct page) * PAGES_PER_SECTION);
+ map = __alloc_bootmem_node_high(NODE_DATA(nid), size,
+ PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
return map;
}
void __init sparse_mem_maps_populate_node(struct page **map_map,
@@ -412,7 +414,8 @@ void __init sparse_mem_maps_populate_node(struct page **map_map,
}
size = PAGE_ALIGN(size);
- map = alloc_bootmem_pages_node(NODE_DATA(nodeid), size * map_count);
+ map = __alloc_bootmem_node_high(NODE_DATA(nodeid), size * map_count,
+ PAGE_SIZE, __pa(MAX_DMA_ADDRESS));
if (map) {
for (pnum = pnum_begin; pnum < pnum_end; pnum++) {
if (!present_section_nr(pnum))
diff --git a/mm/swap.c b/mm/swap.c
index 7cd60bf0a97..3ce7bc373a5 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -224,6 +224,7 @@ void __lru_cache_add(struct page *page, enum lru_list lru)
____pagevec_lru_add(pvec, lru);
put_cpu_var(lru_add_pvecs);
}
+EXPORT_SYMBOL(__lru_cache_add);
/**
* lru_cache_add_lru - add a page to a page list
diff --git a/mm/truncate.c b/mm/truncate.c
index f42675a3615..937571b8b23 100644
--- a/mm/truncate.c
+++ b/mm/truncate.c
@@ -548,18 +548,18 @@ EXPORT_SYMBOL(truncate_pagecache);
* NOTE! We have to be ready to update the memory sharing
* between the file and the memory map for a potential last
* incomplete page. Ugly, but necessary.
+ *
+ * This function is deprecated and simple_setsize or truncate_pagecache
+ * should be used instead.
*/
int vmtruncate(struct inode *inode, loff_t offset)
{
- loff_t oldsize;
int error;
- error = inode_newsize_ok(inode, offset);
+ error = simple_setsize(inode, offset);
if (error)
return error;
- oldsize = inode->i_size;
- i_size_write(inode, offset);
- truncate_pagecache(inode, oldsize, offset);
+
if (inode->i_op->truncate)
inode->i_op->truncate(inode);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 3ff3311447f..915dceb487c 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -73,10 +73,14 @@ struct scan_control {
int swappiness;
- int all_unreclaimable;
-
int order;
+ /*
+ * Intend to reclaim enough contenious memory rather than to reclaim
+ * enough amount memory. I.e, it's the mode for high order allocation.
+ */
+ bool lumpy_reclaim_mode;
+
/* Which cgroup do we reclaim from */
struct mem_cgroup *mem_cgroup;
@@ -85,12 +89,6 @@ struct scan_control {
* are scanned.
*/
nodemask_t *nodemask;
-
- /* Pluggable isolate pages callback */
- unsigned long (*isolate_pages)(unsigned long nr, struct list_head *dst,
- unsigned long *scanned, int order, int mode,
- struct zone *z, struct mem_cgroup *mem_cont,
- int active, int file);
};
#define lru_to_page(_head) (list_entry((_head)->prev, struct page, lru))
@@ -575,7 +573,7 @@ static enum page_references page_check_references(struct page *page,
referenced_page = TestClearPageReferenced(page);
/* Lumpy reclaim - ignore references */
- if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
+ if (sc->lumpy_reclaim_mode)
return PAGEREF_RECLAIM;
/*
@@ -839,11 +837,6 @@ keep:
return nr_reclaimed;
}
-/* LRU Isolation modes. */
-#define ISOLATE_INACTIVE 0 /* Isolate inactive pages. */
-#define ISOLATE_ACTIVE 1 /* Isolate active pages. */
-#define ISOLATE_BOTH 2 /* Isolate both active and inactive pages. */
-
/*
* Attempt to remove the specified page from its LRU. Only take this page
* if it is of the appropriate PageActive status. Pages which are being
@@ -1011,7 +1004,6 @@ static unsigned long isolate_pages_global(unsigned long nr,
struct list_head *dst,
unsigned long *scanned, int order,
int mode, struct zone *z,
- struct mem_cgroup *mem_cont,
int active, int file)
{
int lru = LRU_BASE;
@@ -1130,7 +1122,6 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
unsigned long nr_scanned = 0;
unsigned long nr_reclaimed = 0;
struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
- int lumpy_reclaim = 0;
while (unlikely(too_many_isolated(zone, file, sc))) {
congestion_wait(BLK_RW_ASYNC, HZ/10);
@@ -1140,17 +1131,6 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
return SWAP_CLUSTER_MAX;
}
- /*
- * If we need a large contiguous chunk of memory, or have
- * trouble getting a small set of contiguous pages, we
- * will reclaim both active and inactive pages.
- *
- * We use the same threshold as pageout congestion_wait below.
- */
- if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
- lumpy_reclaim = 1;
- else if (sc->order && priority < DEF_PRIORITY - 2)
- lumpy_reclaim = 1;
pagevec_init(&pvec, 1);
@@ -1163,15 +1143,15 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
unsigned long nr_freed;
unsigned long nr_active;
unsigned int count[NR_LRU_LISTS] = { 0, };
- int mode = lumpy_reclaim ? ISOLATE_BOTH : ISOLATE_INACTIVE;
+ int mode = sc->lumpy_reclaim_mode ? ISOLATE_BOTH : ISOLATE_INACTIVE;
unsigned long nr_anon;
unsigned long nr_file;
- nr_taken = sc->isolate_pages(SWAP_CLUSTER_MAX,
- &page_list, &nr_scan, sc->order, mode,
- zone, sc->mem_cgroup, 0, file);
-
if (scanning_global_lru(sc)) {
+ nr_taken = isolate_pages_global(SWAP_CLUSTER_MAX,
+ &page_list, &nr_scan,
+ sc->order, mode,
+ zone, 0, file);
zone->pages_scanned += nr_scan;
if (current_is_kswapd())
__count_zone_vm_events(PGSCAN_KSWAPD, zone,
@@ -1179,6 +1159,16 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
else
__count_zone_vm_events(PGSCAN_DIRECT, zone,
nr_scan);
+ } else {
+ nr_taken = mem_cgroup_isolate_pages(SWAP_CLUSTER_MAX,
+ &page_list, &nr_scan,
+ sc->order, mode,
+ zone, sc->mem_cgroup,
+ 0, file);
+ /*
+ * mem_cgroup_isolate_pages() keeps track of
+ * scanned pages on its own.
+ */
}
if (nr_taken == 0)
@@ -1216,7 +1206,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
* but that should be acceptable to the caller
*/
if (nr_freed < nr_taken && !current_is_kswapd() &&
- lumpy_reclaim) {
+ sc->lumpy_reclaim_mode) {
congestion_wait(BLK_RW_ASYNC, HZ/10);
/*
@@ -1356,16 +1346,23 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
lru_add_drain();
spin_lock_irq(&zone->lru_lock);
- nr_taken = sc->isolate_pages(nr_pages, &l_hold, &pgscanned, sc->order,
- ISOLATE_ACTIVE, zone,
- sc->mem_cgroup, 1, file);
- /*
- * zone->pages_scanned is used for detect zone's oom
- * mem_cgroup remembers nr_scan by itself.
- */
if (scanning_global_lru(sc)) {
+ nr_taken = isolate_pages_global(nr_pages, &l_hold,
+ &pgscanned, sc->order,
+ ISOLATE_ACTIVE, zone,
+ 1, file);
zone->pages_scanned += pgscanned;
+ } else {
+ nr_taken = mem_cgroup_isolate_pages(nr_pages, &l_hold,
+ &pgscanned, sc->order,
+ ISOLATE_ACTIVE, zone,
+ sc->mem_cgroup, 1, file);
+ /*
+ * mem_cgroup_isolate_pages() keeps track of
+ * scanned pages on its own.
+ */
}
+
reclaim_stat->recent_scanned[file] += nr_taken;
__count_zone_vm_events(PGREFILL, zone, pgscanned);
@@ -1519,21 +1516,52 @@ static unsigned long shrink_list(enum lru_list lru, unsigned long nr_to_scan,
}
/*
+ * Smallish @nr_to_scan's are deposited in @nr_saved_scan,
+ * until we collected @swap_cluster_max pages to scan.
+ */
+static unsigned long nr_scan_try_batch(unsigned long nr_to_scan,
+ unsigned long *nr_saved_scan)
+{
+ unsigned long nr;
+
+ *nr_saved_scan += nr_to_scan;
+ nr = *nr_saved_scan;
+
+ if (nr >= SWAP_CLUSTER_MAX)
+ *nr_saved_scan = 0;
+ else
+ nr = 0;
+
+ return nr;
+}
+
+/*
* Determine how aggressively the anon and file LRU lists should be
* scanned. The relative value of each set of LRU lists is determined
* by looking at the fraction of the pages scanned we did rotate back
* onto the active list instead of evict.
*
- * percent[0] specifies how much pressure to put on ram/swap backed
- * memory, while percent[1] determines pressure on the file LRUs.
+ * nr[0] = anon pages to scan; nr[1] = file pages to scan
*/
-static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
- unsigned long *percent)
+static void get_scan_count(struct zone *zone, struct scan_control *sc,
+ unsigned long *nr, int priority)
{
unsigned long anon, file, free;
unsigned long anon_prio, file_prio;
unsigned long ap, fp;
struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
+ u64 fraction[2], denominator;
+ enum lru_list l;
+ int noswap = 0;
+
+ /* If we have no swap space, do not bother scanning anon pages. */
+ if (!sc->may_swap || (nr_swap_pages <= 0)) {
+ noswap = 1;
+ fraction[0] = 0;
+ fraction[1] = 1;
+ denominator = 1;
+ goto out;
+ }
anon = zone_nr_lru_pages(zone, sc, LRU_ACTIVE_ANON) +
zone_nr_lru_pages(zone, sc, LRU_INACTIVE_ANON);
@@ -1545,9 +1573,10 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
/* If we have very few page cache pages,
force-scan anon pages. */
if (unlikely(file + free <= high_wmark_pages(zone))) {
- percent[0] = 100;
- percent[1] = 0;
- return;
+ fraction[0] = 1;
+ fraction[1] = 0;
+ denominator = 1;
+ goto out;
}
}
@@ -1594,29 +1623,37 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
fp = (file_prio + 1) * (reclaim_stat->recent_scanned[1] + 1);
fp /= reclaim_stat->recent_rotated[1] + 1;
- /* Normalize to percentages */
- percent[0] = 100 * ap / (ap + fp + 1);
- percent[1] = 100 - percent[0];
+ fraction[0] = ap;
+ fraction[1] = fp;
+ denominator = ap + fp + 1;
+out:
+ for_each_evictable_lru(l) {
+ int file = is_file_lru(l);
+ unsigned long scan;
+
+ scan = zone_nr_lru_pages(zone, sc, l);
+ if (priority || noswap) {
+ scan >>= priority;
+ scan = div64_u64(scan * fraction[file], denominator);
+ }
+ nr[l] = nr_scan_try_batch(scan,
+ &reclaim_stat->nr_saved_scan[l]);
+ }
}
-/*
- * Smallish @nr_to_scan's are deposited in @nr_saved_scan,
- * until we collected @swap_cluster_max pages to scan.
- */
-static unsigned long nr_scan_try_batch(unsigned long nr_to_scan,
- unsigned long *nr_saved_scan)
+static void set_lumpy_reclaim_mode(int priority, struct scan_control *sc)
{
- unsigned long nr;
-
- *nr_saved_scan += nr_to_scan;
- nr = *nr_saved_scan;
-
- if (nr >= SWAP_CLUSTER_MAX)
- *nr_saved_scan = 0;
+ /*
+ * If we need a large contiguous chunk of memory, or have
+ * trouble getting a small set of contiguous pages, we
+ * will reclaim both active and inactive pages.
+ */
+ if (sc->order > PAGE_ALLOC_COSTLY_ORDER)
+ sc->lumpy_reclaim_mode = 1;
+ else if (sc->order && priority < DEF_PRIORITY - 2)
+ sc->lumpy_reclaim_mode = 1;
else
- nr = 0;
-
- return nr;
+ sc->lumpy_reclaim_mode = 0;
}
/*
@@ -1627,33 +1664,13 @@ static void shrink_zone(int priority, struct zone *zone,
{
unsigned long nr[NR_LRU_LISTS];
unsigned long nr_to_scan;
- unsigned long percent[2]; /* anon @ 0; file @ 1 */
enum lru_list l;
unsigned long nr_reclaimed = sc->nr_reclaimed;
unsigned long nr_to_reclaim = sc->nr_to_reclaim;
- struct zone_reclaim_stat *reclaim_stat = get_reclaim_stat(zone, sc);
- int noswap = 0;
-
- /* If we have no swap space, do not bother scanning anon pages. */
- if (!sc->may_swap || (nr_swap_pages <= 0)) {
- noswap = 1;
- percent[0] = 0;
- percent[1] = 100;
- } else
- get_scan_ratio(zone, sc, percent);
- for_each_evictable_lru(l) {
- int file = is_file_lru(l);
- unsigned long scan;
+ get_scan_count(zone, sc, nr, priority);
- scan = zone_nr_lru_pages(zone, sc, l);
- if (priority || noswap) {
- scan >>= priority;
- scan = (scan * percent[file]) / 100;
- }
- nr[l] = nr_scan_try_batch(scan,
- &reclaim_stat->nr_saved_scan[l]);
- }
+ set_lumpy_reclaim_mode(priority, sc);
while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] ||
nr[LRU_INACTIVE_FILE]) {
@@ -1707,14 +1724,14 @@ static void shrink_zone(int priority, struct zone *zone,
* If a zone is deemed to be full of pinned pages then just give it a light
* scan then give up on it.
*/
-static void shrink_zones(int priority, struct zonelist *zonelist,
+static int shrink_zones(int priority, struct zonelist *zonelist,
struct scan_control *sc)
{
enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
struct zoneref *z;
struct zone *zone;
+ int progress = 0;
- sc->all_unreclaimable = 1;
for_each_zone_zonelist_nodemask(zone, z, zonelist, high_zoneidx,
sc->nodemask) {
if (!populated_zone(zone))
@@ -1730,19 +1747,19 @@ static void shrink_zones(int priority, struct zonelist *zonelist,
if (zone->all_unreclaimable && priority != DEF_PRIORITY)
continue; /* Let kswapd poll it */
- sc->all_unreclaimable = 0;
} else {
/*
* Ignore cpuset limitation here. We just want to reduce
* # of used pages by us regardless of memory shortage.
*/
- sc->all_unreclaimable = 0;
mem_cgroup_note_reclaim_priority(sc->mem_cgroup,
priority);
}
shrink_zone(priority, zone, sc);
+ progress = 1;
}
+ return progress;
}
/*
@@ -1774,6 +1791,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
enum zone_type high_zoneidx = gfp_zone(sc->gfp_mask);
unsigned long writeback_threshold;
+ get_mems_allowed();
delayacct_freepages_start();
if (scanning_global_lru(sc))
@@ -1795,7 +1813,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
sc->nr_scanned = 0;
if (!priority)
disable_swap_token();
- shrink_zones(priority, zonelist, sc);
+ ret = shrink_zones(priority, zonelist, sc);
/*
* Don't shrink slabs when reclaiming memory from
* over limit cgroups
@@ -1832,7 +1850,7 @@ static unsigned long do_try_to_free_pages(struct zonelist *zonelist,
congestion_wait(BLK_RW_ASYNC, HZ/10);
}
/* top priority shrink_zones still had more to do? don't OOM, then */
- if (!sc->all_unreclaimable && scanning_global_lru(sc))
+ if (ret && scanning_global_lru(sc))
ret = sc->nr_reclaimed;
out:
/*
@@ -1857,6 +1875,7 @@ out:
mem_cgroup_record_reclaim_priority(sc->mem_cgroup, priority);
delayacct_freepages_end();
+ put_mems_allowed();
return ret;
}
@@ -1873,7 +1892,6 @@ unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
.swappiness = vm_swappiness,
.order = order,
.mem_cgroup = NULL,
- .isolate_pages = isolate_pages_global,
.nodemask = nodemask,
};
@@ -1894,7 +1912,6 @@ unsigned long mem_cgroup_shrink_node_zone(struct mem_cgroup *mem,
.swappiness = swappiness,
.order = 0,
.mem_cgroup = mem,
- .isolate_pages = mem_cgroup_isolate_pages,
};
nodemask_t nm = nodemask_of_node(nid);
@@ -1928,7 +1945,6 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
.swappiness = swappiness,
.order = 0,
.mem_cgroup = mem_cont,
- .isolate_pages = mem_cgroup_isolate_pages,
.nodemask = NULL, /* we don't care the placement */
};
@@ -2006,7 +2022,6 @@ static unsigned long balance_pgdat(pg_data_t *pgdat, int order)
.swappiness = vm_swappiness,
.order = order,
.mem_cgroup = NULL,
- .isolate_pages = isolate_pages_global,
};
/*
* temp_priority is used to remember the scanning priority at which
@@ -2385,7 +2400,6 @@ unsigned long shrink_all_memory(unsigned long nr_to_reclaim)
.hibernation_mode = 1,
.swappiness = vm_swappiness,
.order = 0,
- .isolate_pages = isolate_pages_global,
};
struct zonelist * zonelist = node_zonelist(numa_node_id(), sc.gfp_mask);
struct task_struct *p = current;
@@ -2570,7 +2584,6 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
.gfp_mask = gfp_mask,
.swappiness = vm_swappiness,
.order = order,
- .isolate_pages = isolate_pages_global,
};
unsigned long slab_reclaimable;
diff --git a/mm/vmstat.c b/mm/vmstat.c
index fa12ea3051f..7759941d4e7 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -16,6 +16,7 @@
#include <linux/cpu.h>
#include <linux/vmstat.h>
#include <linux/sched.h>
+#include <linux/math64.h>
#ifdef CONFIG_VM_EVENT_COUNTERS
DEFINE_PER_CPU(struct vm_event_state, vm_event_states) = {{0}};
@@ -379,7 +380,86 @@ void zone_statistics(struct zone *preferred_zone, struct zone *z)
}
#endif
-#ifdef CONFIG_PROC_FS
+#ifdef CONFIG_COMPACTION
+struct contig_page_info {
+ unsigned long free_pages;
+ unsigned long free_blocks_total;
+ unsigned long free_blocks_suitable;
+};
+
+/*
+ * Calculate the number of free pages in a zone, how many contiguous
+ * pages are free and how many are large enough to satisfy an allocation of
+ * the target size. Note that this function makes no attempt to estimate
+ * how many suitable free blocks there *might* be if MOVABLE pages were
+ * migrated. Calculating that is possible, but expensive and can be
+ * figured out from userspace
+ */
+static void fill_contig_page_info(struct zone *zone,
+ unsigned int suitable_order,
+ struct contig_page_info *info)
+{
+ unsigned int order;
+
+ info->free_pages = 0;
+ info->free_blocks_total = 0;
+ info->free_blocks_suitable = 0;
+
+ for (order = 0; order < MAX_ORDER; order++) {
+ unsigned long blocks;
+
+ /* Count number of free blocks */
+ blocks = zone->free_area[order].nr_free;
+ info->free_blocks_total += blocks;
+
+ /* Count free base pages */
+ info->free_pages += blocks << order;
+
+ /* Count the suitable free blocks */
+ if (order >= suitable_order)
+ info->free_blocks_suitable += blocks <<
+ (order - suitable_order);
+ }
+}
+
+/*
+ * A fragmentation index only makes sense if an allocation of a requested
+ * size would fail. If that is true, the fragmentation index indicates
+ * whether external fragmentation or a lack of memory was the problem.
+ * The value can be used to determine if page reclaim or compaction
+ * should be used
+ */
+static int __fragmentation_index(unsigned int order, struct contig_page_info *info)
+{
+ unsigned long requested = 1UL << order;
+
+ if (!info->free_blocks_total)
+ return 0;
+
+ /* Fragmentation index only makes sense when a request would fail */
+ if (info->free_blocks_suitable)
+ return -1000;
+
+ /*
+ * Index is between 0 and 1 so return within 3 decimal places
+ *
+ * 0 => allocation would fail due to lack of memory
+ * 1 => allocation would fail due to fragmentation
+ */
+ return 1000 - div_u64( (1000+(div_u64(info->free_pages * 1000ULL, requested))), info->free_blocks_total);
+}
+
+/* Same as __fragmentation index but allocs contig_page_info on stack */
+int fragmentation_index(struct zone *zone, unsigned int order)
+{
+ struct contig_page_info info;
+
+ fill_contig_page_info(zone, order, &info);
+ return __fragmentation_index(order, &info);
+}
+#endif
+
+#if defined(CONFIG_PROC_FS) || defined(CONFIG_COMPACTION)
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
@@ -432,7 +512,9 @@ static void walk_zones_in_node(struct seq_file *m, pg_data_t *pgdat,
spin_unlock_irqrestore(&zone->lock, flags);
}
}
+#endif
+#ifdef CONFIG_PROC_FS
static void frag_show_print(struct seq_file *m, pg_data_t *pgdat,
struct zone *zone)
{
@@ -693,6 +775,16 @@ static const char * const vmstat_text[] = {
"allocstall",
"pgrotated",
+
+#ifdef CONFIG_COMPACTION
+ "compact_blocks_moved",
+ "compact_pages_moved",
+ "compact_pagemigrate_failed",
+ "compact_stall",
+ "compact_fail",
+ "compact_success",
+#endif
+
#ifdef CONFIG_HUGETLB_PAGE
"htlb_buddy_alloc_success",
"htlb_buddy_alloc_fail",
@@ -954,3 +1046,162 @@ static int __init setup_vmstat(void)
return 0;
}
module_init(setup_vmstat)
+
+#if defined(CONFIG_DEBUG_FS) && defined(CONFIG_COMPACTION)
+#include <linux/debugfs.h>
+
+static struct dentry *extfrag_debug_root;
+
+/*
+ * Return an index indicating how much of the available free memory is
+ * unusable for an allocation of the requested size.
+ */
+static int unusable_free_index(unsigned int order,
+ struct contig_page_info *info)
+{
+ /* No free memory is interpreted as all free memory is unusable */
+ if (info->free_pages == 0)
+ return 1000;
+
+ /*
+ * Index should be a value between 0 and 1. Return a value to 3
+ * decimal places.
+ *
+ * 0 => no fragmentation
+ * 1 => high fragmentation
+ */
+ return div_u64((info->free_pages - (info->free_blocks_suitable << order)) * 1000ULL, info->free_pages);
+
+}
+
+static void unusable_show_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ unsigned int order;
+ int index;
+ struct contig_page_info info;
+
+ seq_printf(m, "Node %d, zone %8s ",
+ pgdat->node_id,
+ zone->name);
+ for (order = 0; order < MAX_ORDER; ++order) {
+ fill_contig_page_info(zone, order, &info);
+ index = unusable_free_index(order, &info);
+ seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+ }
+
+ seq_putc(m, '\n');
+}
+
+/*
+ * Display unusable free space index
+ *
+ * The unusable free space index measures how much of the available free
+ * memory cannot be used to satisfy an allocation of a given size and is a
+ * value between 0 and 1. The higher the value, the more of free memory is
+ * unusable and by implication, the worse the external fragmentation is. This
+ * can be expressed as a percentage by multiplying by 100.
+ */
+static int unusable_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ /* check memoryless node */
+ if (!node_state(pgdat->node_id, N_HIGH_MEMORY))
+ return 0;
+
+ walk_zones_in_node(m, pgdat, unusable_show_print);
+
+ return 0;
+}
+
+static const struct seq_operations unusable_op = {
+ .start = frag_start,
+ .next = frag_next,
+ .stop = frag_stop,
+ .show = unusable_show,
+};
+
+static int unusable_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &unusable_op);
+}
+
+static const struct file_operations unusable_file_ops = {
+ .open = unusable_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static void extfrag_show_print(struct seq_file *m,
+ pg_data_t *pgdat, struct zone *zone)
+{
+ unsigned int order;
+ int index;
+
+ /* Alloc on stack as interrupts are disabled for zone walk */
+ struct contig_page_info info;
+
+ seq_printf(m, "Node %d, zone %8s ",
+ pgdat->node_id,
+ zone->name);
+ for (order = 0; order < MAX_ORDER; ++order) {
+ fill_contig_page_info(zone, order, &info);
+ index = __fragmentation_index(order, &info);
+ seq_printf(m, "%d.%03d ", index / 1000, index % 1000);
+ }
+
+ seq_putc(m, '\n');
+}
+
+/*
+ * Display fragmentation index for orders that allocations would fail for
+ */
+static int extfrag_show(struct seq_file *m, void *arg)
+{
+ pg_data_t *pgdat = (pg_data_t *)arg;
+
+ walk_zones_in_node(m, pgdat, extfrag_show_print);
+
+ return 0;
+}
+
+static const struct seq_operations extfrag_op = {
+ .start = frag_start,
+ .next = frag_next,
+ .stop = frag_stop,
+ .show = extfrag_show,
+};
+
+static int extfrag_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &extfrag_op);
+}
+
+static const struct file_operations extfrag_file_ops = {
+ .open = extfrag_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+static int __init extfrag_debug_init(void)
+{
+ extfrag_debug_root = debugfs_create_dir("extfrag", NULL);
+ if (!extfrag_debug_root)
+ return -ENOMEM;
+
+ if (!debugfs_create_file("unusable_index", 0444,
+ extfrag_debug_root, NULL, &unusable_file_ops))
+ return -ENOMEM;
+
+ if (!debugfs_create_file("extfrag_index", 0444,
+ extfrag_debug_root, NULL, &extfrag_file_ops))
+ return -ENOMEM;
+
+ return 0;
+}
+
+module_init(extfrag_debug_init);
+#endif