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-rw-r--r--mm/page_alloc.c754
1 files changed, 475 insertions, 279 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0727896a88ac..a5f3c278c573 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -162,17 +162,25 @@ static unsigned long __meminitdata dma_reserve;
#if MAX_NUMNODES > 1
int nr_node_ids __read_mostly = MAX_NUMNODES;
+int nr_online_nodes __read_mostly = 1;
EXPORT_SYMBOL(nr_node_ids);
+EXPORT_SYMBOL(nr_online_nodes);
#endif
int page_group_by_mobility_disabled __read_mostly;
static void set_pageblock_migratetype(struct page *page, int migratetype)
{
+
+ if (unlikely(page_group_by_mobility_disabled))
+ migratetype = MIGRATE_UNMOVABLE;
+
set_pageblock_flags_group(page, (unsigned long)migratetype,
PB_migrate, PB_migrate_end);
}
+bool oom_killer_disabled __read_mostly;
+
#ifdef CONFIG_DEBUG_VM
static int page_outside_zone_boundaries(struct zone *zone, struct page *page)
{
@@ -295,23 +303,6 @@ void prep_compound_page(struct page *page, unsigned long order)
}
}
-#ifdef CONFIG_HUGETLBFS
-void prep_compound_gigantic_page(struct page *page, unsigned long order)
-{
- int i;
- int nr_pages = 1 << order;
- struct page *p = page + 1;
-
- set_compound_page_dtor(page, free_compound_page);
- set_compound_order(page, order);
- __SetPageHead(page);
- for (i = 1; i < nr_pages; i++, p = mem_map_next(p, page, i)) {
- __SetPageTail(p);
- p->first_page = page;
- }
-}
-#endif
-
static int destroy_compound_page(struct page *page, unsigned long order)
{
int i;
@@ -418,7 +409,7 @@ static inline int page_is_buddy(struct page *page, struct page *buddy,
return 0;
if (PageBuddy(buddy) && page_order(buddy) == order) {
- BUG_ON(page_count(buddy) != 0);
+ VM_BUG_ON(page_count(buddy) != 0);
return 1;
}
return 0;
@@ -449,22 +440,22 @@ static inline int page_is_buddy(struct page *page, struct page *buddy,
*/
static inline void __free_one_page(struct page *page,
- struct zone *zone, unsigned int order)
+ struct zone *zone, unsigned int order,
+ int migratetype)
{
unsigned long page_idx;
- int order_size = 1 << order;
- int migratetype = get_pageblock_migratetype(page);
if (unlikely(PageCompound(page)))
if (unlikely(destroy_compound_page(page, order)))
return;
+ VM_BUG_ON(migratetype == -1);
+
page_idx = page_to_pfn(page) & ((1 << MAX_ORDER) - 1);
- VM_BUG_ON(page_idx & (order_size - 1));
+ VM_BUG_ON(page_idx & ((1 << order) - 1));
VM_BUG_ON(bad_range(zone, page));
- __mod_zone_page_state(zone, NR_FREE_PAGES, order_size);
while (order < MAX_ORDER-1) {
unsigned long combined_idx;
struct page *buddy;
@@ -488,12 +479,27 @@ static inline void __free_one_page(struct page *page,
zone->free_area[order].nr_free++;
}
+#ifdef CONFIG_HAVE_MLOCKED_PAGE_BIT
+/*
+ * free_page_mlock() -- clean up attempts to free and mlocked() page.
+ * Page should not be on lru, so no need to fix that up.
+ * free_pages_check() will verify...
+ */
+static inline void free_page_mlock(struct page *page)
+{
+ __ClearPageMlocked(page);
+ __dec_zone_page_state(page, NR_MLOCK);
+ __count_vm_event(UNEVICTABLE_MLOCKFREED);
+}
+#else
+static void free_page_mlock(struct page *page) { }
+#endif
+
static inline int free_pages_check(struct page *page)
{
- free_page_mlock(page);
if (unlikely(page_mapcount(page) |
(page->mapping != NULL) |
- (page_count(page) != 0) |
+ (atomic_read(&page->_count) != 0) |
(page->flags & PAGE_FLAGS_CHECK_AT_FREE))) {
bad_page(page);
return 1;
@@ -520,6 +526,8 @@ static void free_pages_bulk(struct zone *zone, int count,
spin_lock(&zone->lock);
zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE);
zone->pages_scanned = 0;
+
+ __mod_zone_page_state(zone, NR_FREE_PAGES, count << order);
while (count--) {
struct page *page;
@@ -527,17 +535,20 @@ static void free_pages_bulk(struct zone *zone, int count,
page = list_entry(list->prev, struct page, lru);
/* have to delete it as __free_one_page list manipulates */
list_del(&page->lru);
- __free_one_page(page, zone, order);
+ __free_one_page(page, zone, order, page_private(page));
}
spin_unlock(&zone->lock);
}
-static void free_one_page(struct zone *zone, struct page *page, int order)
+static void free_one_page(struct zone *zone, struct page *page, int order,
+ int migratetype)
{
spin_lock(&zone->lock);
zone_clear_flag(zone, ZONE_ALL_UNRECLAIMABLE);
zone->pages_scanned = 0;
- __free_one_page(page, zone, order);
+
+ __mod_zone_page_state(zone, NR_FREE_PAGES, 1 << order);
+ __free_one_page(page, zone, order, migratetype);
spin_unlock(&zone->lock);
}
@@ -546,6 +557,7 @@ static void __free_pages_ok(struct page *page, unsigned int order)
unsigned long flags;
int i;
int bad = 0;
+ int clearMlocked = PageMlocked(page);
kmemcheck_free_shadow(page, order);
@@ -563,8 +575,11 @@ static void __free_pages_ok(struct page *page, unsigned int order)
kernel_map_pages(page, 1 << order, 0);
local_irq_save(flags);
+ if (unlikely(clearMlocked))
+ free_page_mlock(page);
__count_vm_events(PGFREE, 1 << order);
- free_one_page(page_zone(page), page, order);
+ free_one_page(page_zone(page), page, order,
+ get_pageblock_migratetype(page));
local_irq_restore(flags);
}
@@ -635,7 +650,7 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
{
if (unlikely(page_mapcount(page) |
(page->mapping != NULL) |
- (page_count(page) != 0) |
+ (atomic_read(&page->_count) != 0) |
(page->flags & PAGE_FLAGS_CHECK_AT_PREP))) {
bad_page(page);
return 1;
@@ -660,7 +675,8 @@ static int prep_new_page(struct page *page, int order, gfp_t gfp_flags)
* Go through the free lists for the given migratetype and remove
* the smallest available page from the freelists
*/
-static struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
+static inline
+struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
int migratetype)
{
unsigned int current_order;
@@ -678,7 +694,6 @@ static struct page *__rmqueue_smallest(struct zone *zone, unsigned int order,
list_del(&page->lru);
rmv_page_order(page);
area->nr_free--;
- __mod_zone_page_state(zone, NR_FREE_PAGES, - (1UL << order));
expand(zone, page, order, current_order, area, migratetype);
return page;
}
@@ -769,8 +784,8 @@ static int move_freepages_block(struct zone *zone, struct page *page,
}
/* Remove an element from the buddy allocator from the fallback list */
-static struct page *__rmqueue_fallback(struct zone *zone, int order,
- int start_migratetype)
+static inline struct page *
+__rmqueue_fallback(struct zone *zone, int order, int start_migratetype)
{
struct free_area * area;
int current_order;
@@ -818,8 +833,6 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order,
/* Remove the page from the freelists */
list_del(&page->lru);
rmv_page_order(page);
- __mod_zone_page_state(zone, NR_FREE_PAGES,
- -(1UL << order));
if (current_order == pageblock_order)
set_pageblock_migratetype(page,
@@ -830,8 +843,7 @@ static struct page *__rmqueue_fallback(struct zone *zone, int order,
}
}
- /* Use MIGRATE_RESERVE rather than fail an allocation */
- return __rmqueue_smallest(zone, order, MIGRATE_RESERVE);
+ return NULL;
}
/*
@@ -843,11 +855,23 @@ static struct page *__rmqueue(struct zone *zone, unsigned int order,
{
struct page *page;
+retry_reserve:
page = __rmqueue_smallest(zone, order, migratetype);
- if (unlikely(!page))
+ if (unlikely(!page) && migratetype != MIGRATE_RESERVE) {
page = __rmqueue_fallback(zone, order, migratetype);
+ /*
+ * Use MIGRATE_RESERVE rather than fail an allocation. goto
+ * is used because __rmqueue_smallest is an inline function
+ * and we want just one call site
+ */
+ if (!page) {
+ migratetype = MIGRATE_RESERVE;
+ goto retry_reserve;
+ }
+ }
+
return page;
}
@@ -881,6 +905,7 @@ static int rmqueue_bulk(struct zone *zone, unsigned int order,
set_page_private(page, migratetype);
list = &page->lru;
}
+ __mod_zone_page_state(zone, NR_FREE_PAGES, -(i << order));
spin_unlock(&zone->lock);
return i;
}
@@ -996,6 +1021,7 @@ static void free_hot_cold_page(struct page *page, int cold)
struct zone *zone = page_zone(page);
struct per_cpu_pages *pcp;
unsigned long flags;
+ int clearMlocked = PageMlocked(page);
kmemcheck_free_shadow(page, 0);
@@ -1012,13 +1038,16 @@ static void free_hot_cold_page(struct page *page, int cold)
kernel_map_pages(page, 1, 0);
pcp = &zone_pcp(zone, get_cpu())->pcp;
+ set_page_private(page, get_pageblock_migratetype(page));
local_irq_save(flags);
+ if (unlikely(clearMlocked))
+ free_page_mlock(page);
__count_vm_event(PGFREE);
+
if (cold)
list_add_tail(&page->lru, &pcp->list);
else
list_add(&page->lru, &pcp->list);
- set_page_private(page, get_pageblock_migratetype(page));
pcp->count++;
if (pcp->count >= pcp->high) {
free_pages_bulk(zone, pcp->batch, &pcp->list, 0);
@@ -1071,14 +1100,15 @@ void split_page(struct page *page, unsigned int order)
* we cheat by calling it from here, in the order > 0 path. Saves a branch
* or two.
*/
-static struct page *buffered_rmqueue(struct zone *preferred_zone,
- struct zone *zone, int order, gfp_t gfp_flags)
+static inline
+struct page *buffered_rmqueue(struct zone *preferred_zone,
+ struct zone *zone, int order, gfp_t gfp_flags,
+ int migratetype)
{
unsigned long flags;
struct page *page;
int cold = !!(gfp_flags & __GFP_COLD);
int cpu;
- int migratetype = allocflags_to_migratetype(gfp_flags);
again:
cpu = get_cpu();
@@ -1115,8 +1145,22 @@ again:
list_del(&page->lru);
pcp->count--;
} else {
+ if (unlikely(gfp_flags & __GFP_NOFAIL)) {
+ /*
+ * __GFP_NOFAIL is not to be used in new code.
+ *
+ * All __GFP_NOFAIL callers should be fixed so that they
+ * properly detect and handle allocation failures.
+ *
+ * We most definitely don't want callers attempting to
+ * allocate greater than single-page units with
+ * __GFP_NOFAIL.
+ */
+ WARN_ON_ONCE(order > 0);
+ }
spin_lock_irqsave(&zone->lock, flags);
page = __rmqueue(zone, order, migratetype);
+ __mod_zone_page_state(zone, NR_FREE_PAGES, -(1 << order));
spin_unlock(&zone->lock);
if (!page)
goto failed;
@@ -1138,10 +1182,15 @@ failed:
return NULL;
}
-#define ALLOC_NO_WATERMARKS 0x01 /* don't check watermarks at all */
-#define ALLOC_WMARK_MIN 0x02 /* use pages_min watermark */
-#define ALLOC_WMARK_LOW 0x04 /* use pages_low watermark */
-#define ALLOC_WMARK_HIGH 0x08 /* use pages_high watermark */
+/* The ALLOC_WMARK bits are used as an index to zone->watermark */
+#define ALLOC_WMARK_MIN WMARK_MIN
+#define ALLOC_WMARK_LOW WMARK_LOW
+#define ALLOC_WMARK_HIGH WMARK_HIGH
+#define ALLOC_NO_WATERMARKS 0x04 /* don't check watermarks at all */
+
+/* Mask to get the watermark bits */
+#define ALLOC_WMARK_MASK (ALLOC_NO_WATERMARKS-1)
+
#define ALLOC_HARDER 0x10 /* try to alloc harder */
#define ALLOC_HIGH 0x20 /* __GFP_HIGH set */
#define ALLOC_CPUSET 0x40 /* check for correct cpuset */
@@ -1399,23 +1448,18 @@ static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
*/
static struct page *
get_page_from_freelist(gfp_t gfp_mask, nodemask_t *nodemask, unsigned int order,
- struct zonelist *zonelist, int high_zoneidx, int alloc_flags)
+ struct zonelist *zonelist, int high_zoneidx, int alloc_flags,
+ struct zone *preferred_zone, int migratetype)
{
struct zoneref *z;
struct page *page = NULL;
int classzone_idx;
- struct zone *zone, *preferred_zone;
+ struct zone *zone;
nodemask_t *allowednodes = NULL;/* zonelist_cache approximation */
int zlc_active = 0; /* set if using zonelist_cache */
int did_zlc_setup = 0; /* just call zlc_setup() one time */
- (void)first_zones_zonelist(zonelist, high_zoneidx, nodemask,
- &preferred_zone);
- if (!preferred_zone)
- return NULL;
-
classzone_idx = zone_idx(preferred_zone);
-
zonelist_scan:
/*
* Scan zonelist, looking for a zone with enough free.
@@ -1430,31 +1474,49 @@ zonelist_scan:
!cpuset_zone_allowed_softwall(zone, gfp_mask))
goto try_next_zone;
+ BUILD_BUG_ON(ALLOC_NO_WATERMARKS < NR_WMARK);
if (!(alloc_flags & ALLOC_NO_WATERMARKS)) {
unsigned long mark;
- if (alloc_flags & ALLOC_WMARK_MIN)
- mark = zone->pages_min;
- else if (alloc_flags & ALLOC_WMARK_LOW)
- mark = zone->pages_low;
- else
- mark = zone->pages_high;
- if (!zone_watermark_ok(zone, order, mark,
- classzone_idx, alloc_flags)) {
- if (!zone_reclaim_mode ||
- !zone_reclaim(zone, gfp_mask, order))
+ int ret;
+
+ mark = zone->watermark[alloc_flags & ALLOC_WMARK_MASK];
+ if (zone_watermark_ok(zone, order, mark,
+ classzone_idx, alloc_flags))
+ goto try_this_zone;
+
+ if (zone_reclaim_mode == 0)
+ goto this_zone_full;
+
+ ret = zone_reclaim(zone, gfp_mask, order);
+ switch (ret) {
+ case ZONE_RECLAIM_NOSCAN:
+ /* did not scan */
+ goto try_next_zone;
+ case ZONE_RECLAIM_FULL:
+ /* scanned but unreclaimable */
+ goto this_zone_full;
+ default:
+ /* did we reclaim enough */
+ if (!zone_watermark_ok(zone, order, mark,
+ classzone_idx, alloc_flags))
goto this_zone_full;
}
}
- page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask);
+try_this_zone:
+ page = buffered_rmqueue(preferred_zone, zone, order,
+ gfp_mask, migratetype);
if (page)
break;
this_zone_full:
if (NUMA_BUILD)
zlc_mark_zone_full(zonelist, z);
try_next_zone:
- if (NUMA_BUILD && !did_zlc_setup) {
- /* we do zlc_setup after the first zone is tried */
+ if (NUMA_BUILD && !did_zlc_setup && nr_online_nodes > 1) {
+ /*
+ * we do zlc_setup after the first zone is tried but only
+ * if there are multiple nodes make it worthwhile
+ */
allowednodes = zlc_setup(zonelist, alloc_flags);
zlc_active = 1;
did_zlc_setup = 1;
@@ -1469,47 +1531,217 @@ try_next_zone:
return page;
}
+static inline int
+should_alloc_retry(gfp_t gfp_mask, unsigned int order,
+ unsigned long pages_reclaimed)
+{
+ /* Do not loop if specifically requested */
+ if (gfp_mask & __GFP_NORETRY)
+ return 0;
+
+ /*
+ * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
+ * means __GFP_NOFAIL, but that may not be true in other
+ * implementations.
+ */
+ if (order <= PAGE_ALLOC_COSTLY_ORDER)
+ return 1;
+
+ /*
+ * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
+ * specified, then we retry until we no longer reclaim any pages
+ * (above), or we've reclaimed an order of pages at least as
+ * large as the allocation's order. In both cases, if the
+ * allocation still fails, we stop retrying.
+ */
+ if (gfp_mask & __GFP_REPEAT && pages_reclaimed < (1 << order))
+ return 1;
+
+ /*
+ * Don't let big-order allocations loop unless the caller
+ * explicitly requests that.
+ */
+ if (gfp_mask & __GFP_NOFAIL)
+ return 1;
+
+ return 0;
+}
+
+static inline struct page *
+__alloc_pages_may_oom(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, struct zone *preferred_zone,
+ int migratetype)
+{
+ struct page *page;
+
+ /* Acquire the OOM killer lock for the zones in zonelist */
+ if (!try_set_zone_oom(zonelist, gfp_mask)) {
+ schedule_timeout_uninterruptible(1);
+ return NULL;
+ }
+
+ /*
+ * Go through the zonelist yet one more time, keep very high watermark
+ * here, this is only to catch a parallel oom killing, we must fail if
+ * we're still under heavy pressure.
+ */
+ page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
+ order, zonelist, high_zoneidx,
+ ALLOC_WMARK_HIGH|ALLOC_CPUSET,
+ preferred_zone, migratetype);
+ if (page)
+ goto out;
+
+ /* The OOM killer will not help higher order allocs */
+ if (order > PAGE_ALLOC_COSTLY_ORDER && !(gfp_mask & __GFP_NOFAIL))
+ goto out;
+
+ /* Exhausted what can be done so it's blamo time */
+ out_of_memory(zonelist, gfp_mask, order);
+
+out:
+ clear_zonelist_oom(zonelist, gfp_mask);
+ return page;
+}
+
+/* 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,
+ 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 = NULL;
+ struct reclaim_state reclaim_state;
+ struct task_struct *p = current;
+
+ cond_resched();
+
+ /* We now go into synchronous reclaim */
+ cpuset_memory_pressure_bump();
+
+ /*
+ * The task's cpuset might have expanded its set of allowable nodes
+ */
+ p->flags |= PF_MEMALLOC;
+ lockdep_set_current_reclaim_state(gfp_mask);
+ reclaim_state.reclaimed_slab = 0;
+ p->reclaim_state = &reclaim_state;
+
+ *did_some_progress = try_to_free_pages(zonelist, order, gfp_mask, nodemask);
+
+ p->reclaim_state = NULL;
+ lockdep_clear_current_reclaim_state();
+ p->flags &= ~PF_MEMALLOC;
+
+ cond_resched();
+
+ if (order != 0)
+ drain_all_pages();
+
+ if (likely(*did_some_progress))
+ page = get_page_from_freelist(gfp_mask, nodemask, order,
+ zonelist, high_zoneidx,
+ alloc_flags, preferred_zone,
+ migratetype);
+ return page;
+}
+
/*
- * This is the 'heart' of the zoned buddy allocator.
+ * This is called in the allocator slow-path if the allocation request is of
+ * sufficient urgency to ignore watermarks and take other desperate measures
*/
-struct page *
-__alloc_pages_internal(gfp_t gfp_mask, unsigned int order,
- struct zonelist *zonelist, nodemask_t *nodemask)
+static inline struct page *
+__alloc_pages_high_priority(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, struct zone *preferred_zone,
+ int migratetype)
+{
+ struct page *page;
+
+ do {
+ page = get_page_from_freelist(gfp_mask, nodemask, order,
+ zonelist, high_zoneidx, ALLOC_NO_WATERMARKS,
+ preferred_zone, migratetype);
+
+ if (!page && gfp_mask & __GFP_NOFAIL)
+ congestion_wait(WRITE, HZ/50);
+ } while (!page && (gfp_mask & __GFP_NOFAIL));
+
+ return page;
+}
+
+static inline
+void wake_all_kswapd(unsigned int order, struct zonelist *zonelist,
+ enum zone_type high_zoneidx)
{
- const gfp_t wait = gfp_mask & __GFP_WAIT;
- enum zone_type high_zoneidx = gfp_zone(gfp_mask);
struct zoneref *z;
struct zone *zone;
- struct page *page;
- struct reclaim_state reclaim_state;
- struct task_struct *p = current;
- int do_retry;
- int alloc_flags;
- unsigned long did_some_progress;
- unsigned long pages_reclaimed = 0;
- lockdep_trace_alloc(gfp_mask);
+ for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
+ wakeup_kswapd(zone, order);
+}
- might_sleep_if(wait);
+static inline int
+gfp_to_alloc_flags(gfp_t gfp_mask)
+{
+ struct task_struct *p = current;
+ int alloc_flags = ALLOC_WMARK_MIN | ALLOC_CPUSET;
+ const gfp_t wait = gfp_mask & __GFP_WAIT;
- if (should_fail_alloc_page(gfp_mask, order))
- return NULL;
+ /* __GFP_HIGH is assumed to be the same as ALLOC_HIGH to save a branch. */
+ BUILD_BUG_ON(__GFP_HIGH != ALLOC_HIGH);
-restart:
- z = zonelist->_zonerefs; /* the list of zones suitable for gfp_mask */
+ /*
+ * The caller may dip into page reserves a bit more if the caller
+ * cannot run direct reclaim, or if the caller has realtime scheduling
+ * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
+ * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
+ */
+ alloc_flags |= (gfp_mask & __GFP_HIGH);
- if (unlikely(!z->zone)) {
+ if (!wait) {
+ alloc_flags |= ALLOC_HARDER;
/*
- * Happens if we have an empty zonelist as a result of
- * GFP_THISNODE being used on a memoryless node
+ * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
+ * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
*/
- return NULL;
+ alloc_flags &= ~ALLOC_CPUSET;
+ } else if (unlikely(rt_task(p)))
+ alloc_flags |= ALLOC_HARDER;
+
+ if (likely(!(gfp_mask & __GFP_NOMEMALLOC))) {
+ if (!in_interrupt() &&
+ ((p->flags & PF_MEMALLOC) ||
+ unlikely(test_thread_flag(TIF_MEMDIE))))
+ alloc_flags |= ALLOC_NO_WATERMARKS;
}
- page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
- zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET);
- if (page)
- goto got_pg;
+ return alloc_flags;
+}
+
+static inline struct page *
+__alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, enum zone_type high_zoneidx,
+ nodemask_t *nodemask, struct zone *preferred_zone,
+ int migratetype)
+{
+ const gfp_t wait = gfp_mask & __GFP_WAIT;
+ struct page *page = NULL;
+ int alloc_flags;
+ unsigned long pages_reclaimed = 0;
+ unsigned long did_some_progress;
+ struct task_struct *p = current;
+
+ /*
+ * In the slowpath, we sanity check order to avoid ever trying to
+ * reclaim >= MAX_ORDER areas which will never succeed. Callers may
+ * be using allocators in order of preference for an area that is
+ * too large.
+ */
+ if (WARN_ON_ONCE(order >= MAX_ORDER))
+ return NULL;
/*
* GFP_THISNODE (meaning __GFP_THISNODE, __GFP_NORETRY and
@@ -1522,154 +1754,83 @@ restart:
if (NUMA_BUILD && (gfp_mask & GFP_THISNODE) == GFP_THISNODE)
goto nopage;
- for_each_zone_zonelist(zone, z, zonelist, high_zoneidx)
- wakeup_kswapd(zone, order);
+ wake_all_kswapd(order, zonelist, high_zoneidx);
/*
* OK, we're below the kswapd watermark and have kicked background
* reclaim. Now things get more complex, so set up alloc_flags according
* to how we want to proceed.
- *
- * The caller may dip into page reserves a bit more if the caller
- * cannot run direct reclaim, or if the caller has realtime scheduling
- * policy or is asking for __GFP_HIGH memory. GFP_ATOMIC requests will
- * set both ALLOC_HARDER (!wait) and ALLOC_HIGH (__GFP_HIGH).
*/
- alloc_flags = ALLOC_WMARK_MIN;
- if ((unlikely(rt_task(p)) && !in_interrupt()) || !wait)
- alloc_flags |= ALLOC_HARDER;
- if (gfp_mask & __GFP_HIGH)
- alloc_flags |= ALLOC_HIGH;
- if (wait)
- alloc_flags |= ALLOC_CPUSET;
+ alloc_flags = gfp_to_alloc_flags(gfp_mask);
- /*
- * Go through the zonelist again. Let __GFP_HIGH and allocations
- * coming from realtime tasks go deeper into reserves.
- *
- * This is the last chance, in general, before the goto nopage.
- * Ignore cpuset if GFP_ATOMIC (!wait) rather than fail alloc.
- * See also cpuset_zone_allowed() comment in kernel/cpuset.c.
- */
+restart:
+ /* This is the last chance, in general, before the goto nopage. */
page = get_page_from_freelist(gfp_mask, nodemask, order, zonelist,
- high_zoneidx, alloc_flags);
+ high_zoneidx, alloc_flags & ~ALLOC_NO_WATERMARKS,
+ preferred_zone, migratetype);
if (page)
goto got_pg;
- /* This allocation should allow future memory freeing. */
-
rebalance:
- if (((p->flags & PF_MEMALLOC) || unlikely(test_thread_flag(TIF_MEMDIE)))
- && !in_interrupt()) {
- if (!(gfp_mask & __GFP_NOMEMALLOC)) {
-nofail_alloc:
- /* go through the zonelist yet again, ignoring mins */
- page = get_page_from_freelist(gfp_mask, nodemask, order,
- zonelist, high_zoneidx, ALLOC_NO_WATERMARKS);
- if (page)
- goto got_pg;
- if (gfp_mask & __GFP_NOFAIL) {
- congestion_wait(WRITE, HZ/50);
- goto nofail_alloc;
- }
- }
- goto nopage;
+ /* Allocate without watermarks if the context allows */
+ if (alloc_flags & ALLOC_NO_WATERMARKS) {
+ page = __alloc_pages_high_priority(gfp_mask, order,
+ zonelist, high_zoneidx, nodemask,
+ preferred_zone, migratetype);
+ if (page)
+ goto got_pg;
}
/* Atomic allocations - we can't balance anything */
if (!wait)
goto nopage;
- cond_resched();
+ /* Avoid recursion of direct reclaim */
+ if (p->flags & PF_MEMALLOC)
+ goto nopage;
+
+ /* Try direct reclaim and then allocating */
+ page = __alloc_pages_direct_reclaim(gfp_mask, order,
+ zonelist, high_zoneidx,
+ nodemask,
+ alloc_flags, preferred_zone,
+ migratetype, &did_some_progress);
+ if (page)
+ goto got_pg;
- /* We now go into synchronous reclaim */
- cpuset_memory_pressure_bump();
/*
- * The task's cpuset might have expanded its set of allowable nodes
+ * If we failed to make any progress reclaiming, then we are
+ * running out of options and have to consider going OOM
*/
- cpuset_update_task_memory_state();
- p->flags |= PF_MEMALLOC;
-
- lockdep_set_current_reclaim_state(gfp_mask);
- reclaim_state.reclaimed_slab = 0;
- p->reclaim_state = &reclaim_state;
-
- did_some_progress = try_to_free_pages(zonelist, order,
- gfp_mask, nodemask);
-
- p->reclaim_state = NULL;
- lockdep_clear_current_reclaim_state();
- p->flags &= ~PF_MEMALLOC;
-
- cond_resched();
+ if (!did_some_progress) {
+ if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
+ if (oom_killer_disabled)
+ goto nopage;
+ page = __alloc_pages_may_oom(gfp_mask, order,
+ zonelist, high_zoneidx,
+ nodemask, preferred_zone,
+ migratetype);
+ if (page)
+ goto got_pg;
- if (order != 0)
- drain_all_pages();
+ /*
+ * The OOM killer does not trigger for high-order
+ * ~__GFP_NOFAIL allocations so if no progress is being
+ * made, there are no other options and retrying is
+ * unlikely to help.
+ */
+ if (order > PAGE_ALLOC_COSTLY_ORDER &&
+ !(gfp_mask & __GFP_NOFAIL))
+ goto nopage;
- if (likely(did_some_progress)) {
- page = get_page_from_freelist(gfp_mask, nodemask, order,
- zonelist, high_zoneidx, alloc_flags);
- if (page)
- goto got_pg;
- } else if ((gfp_mask & __GFP_FS) && !(gfp_mask & __GFP_NORETRY)) {
- if (!try_set_zone_oom(zonelist, gfp_mask)) {
- schedule_timeout_uninterruptible(1);
goto restart;
}
-
- /*
- * Go through the zonelist yet one more time, keep
- * very high watermark here, this is only to catch
- * a parallel oom killing, we must fail if we're still
- * under heavy pressure.
- */
- page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask,
- order, zonelist, high_zoneidx,
- ALLOC_WMARK_HIGH|ALLOC_CPUSET);
- if (page) {
- clear_zonelist_oom(zonelist, gfp_mask);
- goto got_pg;
- }
-
- /* The OOM killer will not help higher order allocs so fail */
- if (order > PAGE_ALLOC_COSTLY_ORDER) {
- clear_zonelist_oom(zonelist, gfp_mask);
- goto nopage;
- }
-
- out_of_memory(zonelist, gfp_mask, order);
- clear_zonelist_oom(zonelist, gfp_mask);
- goto restart;
}
- /*
- * Don't let big-order allocations loop unless the caller explicitly
- * requests that. Wait for some write requests to complete then retry.
- *
- * In this implementation, order <= PAGE_ALLOC_COSTLY_ORDER
- * means __GFP_NOFAIL, but that may not be true in other
- * implementations.
- *
- * For order > PAGE_ALLOC_COSTLY_ORDER, if __GFP_REPEAT is
- * specified, then we retry until we no longer reclaim any pages
- * (above), or we've reclaimed an order of pages at least as
- * large as the allocation's order. In both cases, if the
- * allocation still fails, we stop retrying.
- */
+ /* Check if we should retry the allocation */
pages_reclaimed += did_some_progress;
- do_retry = 0;
- if (!(gfp_mask & __GFP_NORETRY)) {
- if (order <= PAGE_ALLOC_COSTLY_ORDER) {
- do_retry = 1;
- } else {
- if (gfp_mask & __GFP_REPEAT &&
- pages_reclaimed < (1 << order))
- do_retry = 1;
- }
- if (gfp_mask & __GFP_NOFAIL)
- do_retry = 1;
- }
- if (do_retry) {
+ if (should_alloc_retry(gfp_mask, order, pages_reclaimed)) {
+ /* Wait for some write requests to complete then retry */
congestion_wait(WRITE, HZ/50);
goto rebalance;
}
@@ -1687,8 +1848,53 @@ got_pg:
if (kmemcheck_enabled)
kmemcheck_pagealloc_alloc(page, order, gfp_mask);
return page;
+
+}
+
+/*
+ * This is the 'heart' of the zoned buddy allocator.
+ */
+struct page *
+__alloc_pages_nodemask(gfp_t gfp_mask, unsigned int order,
+ struct zonelist *zonelist, nodemask_t *nodemask)
+{
+ enum zone_type high_zoneidx = gfp_zone(gfp_mask);
+ struct zone *preferred_zone;
+ struct page *page;
+ int migratetype = allocflags_to_migratetype(gfp_mask);
+
+ lockdep_trace_alloc(gfp_mask);
+
+ might_sleep_if(gfp_mask & __GFP_WAIT);
+
+ if (should_fail_alloc_page(gfp_mask, order))
+ return NULL;
+
+ /*
+ * Check the zones suitable for the gfp_mask contain at least one
+ * valid zone. It's possible to have an empty zonelist as a result
+ * of GFP_THISNODE and a memoryless node
+ */
+ if (unlikely(!zonelist->_zonerefs->zone))
+ return NULL;
+
+ /* The preferred zone is used for statistics later */
+ first_zones_zonelist(zonelist, high_zoneidx, nodemask, &preferred_zone);
+ if (!preferred_zone)
+ return NULL;
+
+ /* First allocation attempt */
+ page = get_page_from_freelist(gfp_mask|__GFP_HARDWALL, nodemask, order,
+ zonelist, high_zoneidx, ALLOC_WMARK_LOW|ALLOC_CPUSET,
+ preferred_zone, migratetype);
+ if (unlikely(!page))
+ page = __alloc_pages_slowpath(gfp_mask, order,
+ zonelist, high_zoneidx, nodemask,
+ preferred_zone, migratetype);
+
+ return page;
}
-EXPORT_SYMBOL(__alloc_pages_internal);
+EXPORT_SYMBOL(__alloc_pages_nodemask);
/*
* Common helper functions.
@@ -1817,7 +2023,7 @@ static unsigned int nr_free_zone_pages(int offset)
for_each_zone_zonelist(zone, z, zonelist, offset) {
unsigned long size = zone->present_pages;
- unsigned long high = zone->pages_high;
+ unsigned long high = high_wmark_pages(zone);
if (size > high)
sum += size - high;
}
@@ -1909,19 +2115,14 @@ void show_free_areas(void)
printk("Active_anon:%lu active_file:%lu inactive_anon:%lu\n"
" inactive_file:%lu"
-//TODO: check/adjust line lengths
-#ifdef CONFIG_UNEVICTABLE_LRU
" unevictable:%lu"
-#endif
" dirty:%lu writeback:%lu unstable:%lu\n"
" free:%lu slab:%lu mapped:%lu pagetables:%lu bounce:%lu\n",
global_page_state(NR_ACTIVE_ANON),
global_page_state(NR_ACTIVE_FILE),
global_page_state(NR_INACTIVE_ANON),
global_page_state(NR_INACTIVE_FILE),
-#ifdef CONFIG_UNEVICTABLE_LRU
global_page_state(NR_UNEVICTABLE),
-#endif
global_page_state(NR_FILE_DIRTY),
global_page_state(NR_WRITEBACK),
global_page_state(NR_UNSTABLE_NFS),
@@ -1945,25 +2146,21 @@ void show_free_areas(void)
" inactive_anon:%lukB"
" active_file:%lukB"
" inactive_file:%lukB"
-#ifdef CONFIG_UNEVICTABLE_LRU
" unevictable:%lukB"
-#endif
" present:%lukB"
" pages_scanned:%lu"
" all_unreclaimable? %s"
"\n",
zone->name,
K(zone_page_state(zone, NR_FREE_PAGES)),
- K(zone->pages_min),
- K(zone->pages_low),
- K(zone->pages_high),
+ K(min_wmark_pages(zone)),
+ K(low_wmark_pages(zone)),
+ K(high_wmark_pages(zone)),
K(zone_page_state(zone, NR_ACTIVE_ANON)),
K(zone_page_state(zone, NR_INACTIVE_ANON)),
K(zone_page_state(zone, NR_ACTIVE_FILE)),
K(zone_page_state(zone, NR_INACTIVE_FILE)),
-#ifdef CONFIG_UNEVICTABLE_LRU
K(zone_page_state(zone, NR_UNEVICTABLE)),
-#endif
K(zone->present_pages),
zone->pages_scanned,
(zone_is_all_unreclaimable(zone) ? "yes" : "no")
@@ -2121,7 +2318,7 @@ int numa_zonelist_order_handler(ctl_table *table, int write,
}
-#define MAX_NODE_LOAD (num_online_nodes())
+#define MAX_NODE_LOAD (nr_online_nodes)
static int node_load[MAX_NUMNODES];
/**
@@ -2330,7 +2527,7 @@ static void build_zonelists(pg_data_t *pgdat)
/* NUMA-aware ordering of nodes */
local_node = pgdat->node_id;
- load = num_online_nodes();
+ load = nr_online_nodes;
prev_node = local_node;
nodes_clear(used_mask);
@@ -2481,7 +2678,7 @@ void build_all_zonelists(void)
printk("Built %i zonelists in %s order, mobility grouping %s. "
"Total pages: %ld\n",
- num_online_nodes(),
+ nr_online_nodes,
zonelist_order_name[current_zonelist_order],
page_group_by_mobility_disabled ? "off" : "on",
vm_total_pages);
@@ -2560,8 +2757,8 @@ static inline unsigned long wait_table_bits(unsigned long size)
/*
* Mark a number of pageblocks as MIGRATE_RESERVE. The number
- * of blocks reserved is based on zone->pages_min. The memory within the
- * reserve will tend to store contiguous free pages. Setting min_free_kbytes
+ * of blocks reserved is based on min_wmark_pages(zone). The memory within
+ * the reserve will tend to store contiguous free pages. Setting min_free_kbytes
* higher will lead to a bigger reserve which will get freed as contiguous
* blocks as reclaim kicks in
*/
@@ -2574,7 +2771,7 @@ static void setup_zone_migrate_reserve(struct zone *zone)
/* Get the start pfn, end pfn and the number of blocks to reserve */
start_pfn = zone->zone_start_pfn;
end_pfn = start_pfn + zone->spanned_pages;
- reserve = roundup(zone->pages_min, pageblock_nr_pages) >>
+ reserve = roundup(min_wmark_pages(zone), pageblock_nr_pages) >>
pageblock_order;
for (pfn = start_pfn; pfn < end_pfn; pfn += pageblock_nr_pages) {
@@ -3506,7 +3703,7 @@ static void __paginginit free_area_init_core(struct pglist_data *pgdat,
zone_pcp_init(zone);
for_each_lru(l) {
INIT_LIST_HEAD(&zone->lru[l].list);
- zone->lru[l].nr_scan = 0;
+ zone->lru[l].nr_saved_scan = 0;
}
zone->reclaim_stat.recent_rotated[0] = 0;
zone->reclaim_stat.recent_rotated[1] = 0;
@@ -4043,6 +4240,11 @@ void __init free_area_init_nodes(unsigned long *max_zone_pfn)
early_node_map[i].start_pfn,
early_node_map[i].end_pfn);
+ /*
+ * find_zone_movable_pfns_for_nodes/early_calculate_totalpages init
+ * that node_mask, clear it at first
+ */
+ nodes_clear(node_states[N_HIGH_MEMORY]);
/* Initialise every node */
mminit_verify_pageflags_layout();
setup_nr_node_ids();
@@ -4177,8 +4379,8 @@ static void calculate_totalreserve_pages(void)
max = zone->lowmem_reserve[j];
}
- /* we treat pages_high as reserved pages. */
- max += zone->pages_high;
+ /* we treat the high watermark as reserved pages. */
+ max += high_wmark_pages(zone);
if (max > zone->present_pages)
max = zone->present_pages;
@@ -4228,12 +4430,13 @@ static void setup_per_zone_lowmem_reserve(void)
}
/**
- * setup_per_zone_pages_min - called when min_free_kbytes changes.
+ * setup_per_zone_wmarks - called when min_free_kbytes changes
+ * or when memory is hot-{added|removed}
*
- * Ensures that the pages_{min,low,high} values for each zone are set correctly
- * with respect to min_free_kbytes.
+ * Ensures that the watermark[min,low,high] values for each zone are set
+ * correctly with respect to min_free_kbytes.
*/
-void setup_per_zone_pages_min(void)
+void setup_per_zone_wmarks(void)
{
unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
unsigned long lowmem_pages = 0;
@@ -4258,7 +4461,7 @@ void setup_per_zone_pages_min(void)
* need highmem pages, so cap pages_min to a small
* value here.
*
- * The (pages_high-pages_low) and (pages_low-pages_min)
+ * The WMARK_HIGH-WMARK_LOW and (WMARK_LOW-WMARK_MIN)
* deltas controls asynch page reclaim, and so should
* not be capped for highmem.
*/
@@ -4269,17 +4472,17 @@ void setup_per_zone_pages_min(void)
min_pages = SWAP_CLUSTER_MAX;
if (min_pages > 128)
min_pages = 128;
- zone->pages_min = min_pages;
+ zone->watermark[WMARK_MIN] = min_pages;
} else {
/*
* If it's a lowmem zone, reserve a number of pages
* proportionate to the zone's size.
*/
- zone->pages_min = tmp;
+ zone->watermark[WMARK_MIN] = tmp;
}
- zone->pages_low = zone->pages_min + (tmp >> 2);
- zone->pages_high = zone->pages_min + (tmp >> 1);
+ zone->watermark[WMARK_LOW] = min_wmark_pages(zone) + (tmp >> 2);
+ zone->watermark[WMARK_HIGH] = min_wmark_pages(zone) + (tmp >> 1);
setup_zone_migrate_reserve(zone);
spin_unlock_irqrestore(&zone->lock, flags);
}
@@ -4289,8 +4492,6 @@ void setup_per_zone_pages_min(void)
}
/**
- * setup_per_zone_inactive_ratio - called when min_free_kbytes changes.
- *
* The inactive anon list should be small enough that the VM never has to
* do too much work, but large enough that each inactive page has a chance
* to be referenced again before it is swapped out.
@@ -4311,21 +4512,26 @@ void setup_per_zone_pages_min(void)
* 1TB 101 10GB
* 10TB 320 32GB
*/
-static void setup_per_zone_inactive_ratio(void)
+void calculate_zone_inactive_ratio(struct zone *zone)
{
- struct zone *zone;
-
- for_each_zone(zone) {
- unsigned int gb, ratio;
+ unsigned int gb, ratio;
- /* Zone size in gigabytes */
- gb = zone->present_pages >> (30 - PAGE_SHIFT);
+ /* Zone size in gigabytes */
+ gb = zone->present_pages >> (30 - PAGE_SHIFT);
+ if (gb)
ratio = int_sqrt(10 * gb);
- if (!ratio)
- ratio = 1;
+ else
+ ratio = 1;
- zone->inactive_ratio = ratio;
- }
+ zone->inactive_ratio = ratio;
+}
+
+static void __init setup_per_zone_inactive_ratio(void)
+{
+ struct zone *zone;
+
+ for_each_zone(zone)
+ calculate_zone_inactive_ratio(zone);
}
/*
@@ -4352,7 +4558,7 @@ static void setup_per_zone_inactive_ratio(void)
* 8192MB: 11584k
* 16384MB: 16384k
*/
-static int __init init_per_zone_pages_min(void)
+static int __init init_per_zone_wmark_min(void)
{
unsigned long lowmem_kbytes;
@@ -4363,12 +4569,12 @@ static int __init init_per_zone_pages_min(void)
min_free_kbytes = 128;
if (min_free_kbytes > 65536)
min_free_kbytes = 65536;
- setup_per_zone_pages_min();
+ setup_per_zone_wmarks();
setup_per_zone_lowmem_reserve();
setup_per_zone_inactive_ratio();
return 0;
}
-module_init(init_per_zone_pages_min)
+module_init(init_per_zone_wmark_min)
/*
* min_free_kbytes_sysctl_handler - just a wrapper around proc_dointvec() so
@@ -4380,7 +4586,7 @@ int min_free_kbytes_sysctl_handler(ctl_table *table, int write,
{
proc_dointvec(table, write, file, buffer, length, ppos);
if (write)
- setup_per_zone_pages_min();
+ setup_per_zone_wmarks();
return 0;
}
@@ -4424,7 +4630,7 @@ int sysctl_min_slab_ratio_sysctl_handler(ctl_table *table, int write,
* whenever sysctl_lowmem_reserve_ratio changes.
*
* The reserve ratio obviously has absolutely no relation with the
- * pages_min watermarks. The lowmem reserve ratio can only make sense
+ * minimum watermarks. The lowmem reserve ratio can only make sense
* if in function of the boot time zone sizes.
*/
int lowmem_reserve_ratio_sysctl_handler(ctl_table *table, int write,
@@ -4531,23 +4737,13 @@ void *__init alloc_large_system_hash(const char *tablename,
else if (hashdist)
table = __vmalloc(size, GFP_ATOMIC, PAGE_KERNEL);
else {
- unsigned long order = get_order(size);
- table = (void*) __get_free_pages(GFP_ATOMIC, order);
/*
* If bucketsize is not a power-of-two, we may free
- * some pages at the end of hash table.
+ * some pages at the end of hash table which
+ * alloc_pages_exact() automatically does
*/
- if (table) {
- unsigned long alloc_end = (unsigned long)table +
- (PAGE_SIZE << order);
- unsigned long used = (unsigned long)table +
- PAGE_ALIGN(size);
- split_page(virt_to_page(table), order);
- while (used < alloc_end) {
- free_page(used);
- used += PAGE_SIZE;
- }
- }
+ if (get_order(size) < MAX_ORDER)
+ table = alloc_pages_exact(size, GFP_ATOMIC);
}
} while (!table && size > PAGE_SIZE && --log2qty);