static DEFINE_MUTEX(pcp_batch_high_lock);
#define MIN_PERCPU_PAGELIST_HIGH_FRACTION (8)
-struct pagesets {
- local_lock_t lock;
-};
-static DEFINE_PER_CPU(struct pagesets, pagesets) = {
- .lock = INIT_LOCAL_LOCK(lock),
-};
+#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT)
+/*
+ * On SMP, spin_trylock is sufficient protection.
+ * On PREEMPT_RT, spin_trylock is equivalent on both SMP and UP.
+ */
+#define pcp_trylock_prepare(flags) do { } while (0)
+#define pcp_trylock_finish(flag) do { } while (0)
+#else
+
+/* UP spin_trylock always succeeds so disable IRQs to prevent re-entrancy. */
+#define pcp_trylock_prepare(flags) local_irq_save(flags)
+#define pcp_trylock_finish(flags) local_irq_restore(flags)
+#endif
+
+/*
+ * Locking a pcp requires a PCP lookup followed by a spinlock. To avoid
+ * a migration causing the wrong PCP to be locked and remote memory being
+ * potentially allocated, pin the task to the CPU for the lookup+lock.
+ * preempt_disable is used on !RT because it is faster than migrate_disable.
+ * migrate_disable is used on RT because otherwise RT spinlock usage is
+ * interfered with and a high priority task cannot preempt the allocator.
+ */
+#ifndef CONFIG_PREEMPT_RT
+#define pcpu_task_pin() preempt_disable()
+#define pcpu_task_unpin() preempt_enable()
+#else
+#define pcpu_task_pin() migrate_disable()
+#define pcpu_task_unpin() migrate_enable()
+#endif
+/*
+ * Generic helper to lookup and a per-cpu variable with an embedded spinlock.
+ * Return value should be used with equivalent unlock helper.
+ */
+#define pcpu_spin_lock(type, member, ptr) \
+({ \
+ type *_ret; \
+ pcpu_task_pin(); \
+ _ret = this_cpu_ptr(ptr); \
+ spin_lock(&_ret->member); \
+ _ret; \
+})
+
+#define pcpu_spin_lock_irqsave(type, member, ptr, flags) \
+({ \
+ type *_ret; \
+ pcpu_task_pin(); \
+ _ret = this_cpu_ptr(ptr); \
+ spin_lock_irqsave(&_ret->member, flags); \
+ _ret; \
+})
+
+#define pcpu_spin_trylock_irqsave(type, member, ptr, flags) \
+({ \
+ type *_ret; \
+ pcpu_task_pin(); \
+ _ret = this_cpu_ptr(ptr); \
+ if (!spin_trylock_irqsave(&_ret->member, flags)) { \
+ pcpu_task_unpin(); \
+ _ret = NULL; \
+ } \
+ _ret; \
+})
+
+#define pcpu_spin_unlock(member, ptr) \
+({ \
+ spin_unlock(&ptr->member); \
+ pcpu_task_unpin(); \
+})
+
+#define pcpu_spin_unlock_irqrestore(member, ptr, flags) \
+({ \
+ spin_unlock_irqrestore(&ptr->member, flags); \
+ pcpu_task_unpin(); \
+})
+
+/* struct per_cpu_pages specific helpers. */
+#define pcp_spin_lock(ptr) \
+ pcpu_spin_lock(struct per_cpu_pages, lock, ptr)
+
+#define pcp_spin_lock_irqsave(ptr, flags) \
+ pcpu_spin_lock_irqsave(struct per_cpu_pages, lock, ptr, flags)
+
+#define pcp_spin_trylock_irqsave(ptr, flags) \
+ pcpu_spin_trylock_irqsave(struct per_cpu_pages, lock, ptr, flags)
+
+#define pcp_spin_unlock(ptr) \
+ pcpu_spin_unlock(lock, ptr)
+
+#define pcp_spin_unlock_irqrestore(ptr, flags) \
+ pcpu_spin_unlock_irqrestore(lock, ptr, flags)
#ifdef CONFIG_USE_PERCPU_NUMA_NODE_ID
DEFINE_PER_CPU(int, numa_node);
EXPORT_PER_CPU_SYMBOL(numa_node);
EXPORT_PER_CPU_SYMBOL(_numa_mem_);
#endif
-/* work_structs for global per-cpu drains */
-struct pcpu_drain {
- struct zone *zone;
- struct work_struct work;
-};
static DEFINE_MUTEX(pcpu_drain_mutex);
-static DEFINE_PER_CPU(struct pcpu_drain, pcpu_drain);
#ifdef CONFIG_GCC_PLUGIN_LATENT_ENTROPY
volatile unsigned long latent_entropy __latent_entropy;
static unsigned long required_movablecore __initdata;
static unsigned long required_movablecore_percent __initdata;
static unsigned long zone_movable_pfn[MAX_NUMNODES] __initdata;
-static bool mirrored_kernelcore __meminitdata;
+bool mirrored_kernelcore __initdata_memblock;
/* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
int movable_zone;
{
unsigned long *bitmap;
unsigned long bitidx, word_bitidx;
- unsigned long old_word, word;
+ unsigned long word;
BUILD_BUG_ON(NR_PAGEBLOCK_BITS != 4);
BUILD_BUG_ON(MIGRATE_TYPES > (1 << PB_migratetype_bits));
flags <<= bitidx;
word = READ_ONCE(bitmap[word_bitidx]);
- for (;;) {
- old_word = cmpxchg(&bitmap[word_bitidx], word, (word & ~mask) | flags);
- if (word == old_word)
- break;
- word = old_word;
- }
+ do {
+ } while (!try_cmpxchg(&bitmap[word_bitidx], &word, (word & ~mask) | flags));
}
void set_pageblock_migratetype(struct page *page, int migratetype)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
if (order > PAGE_ALLOC_COSTLY_ORDER) {
VM_BUG_ON(order != pageblock_order);
- base = PAGE_ALLOC_COSTLY_ORDER + 1;
+ return NR_LOWORDER_PCP_LISTS;
}
#else
VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
int order = pindex / MIGRATE_PCPTYPES;
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
- if (order > PAGE_ALLOC_COSTLY_ORDER)
+ if (pindex == NR_LOWORDER_PCP_LISTS)
order = pageblock_order;
#else
VM_BUG_ON(order > PAGE_ALLOC_COSTLY_ORDER);
prep_compound_head(page, order);
}
+void destroy_large_folio(struct folio *folio)
+{
+ enum compound_dtor_id dtor = folio_page(folio, 1)->compound_dtor;
+
+ VM_BUG_ON_FOLIO(dtor >= NR_COMPOUND_DTORS, folio);
+ compound_page_dtors[dtor](&folio->page);
+}
+
#ifdef CONFIG_DEBUG_PAGEALLOC
unsigned int _debug_guardpage_minorder;
return false;
__SetPageGuard(page);
- INIT_LIST_HEAD(&page->lru);
+ INIT_LIST_HEAD(&page->buddy_list);
set_page_private(page, order);
/* Guard pages are not available for any usage */
__mod_zone_freepage_state(zone, -(1 << order), migratetype);
{
struct free_area *area = &zone->free_area[order];
- list_add(&page->lru, &area->free_list[migratetype]);
+ list_add(&page->buddy_list, &area->free_list[migratetype]);
area->nr_free++;
}
{
struct free_area *area = &zone->free_area[order];
- list_add_tail(&page->lru, &area->free_list[migratetype]);
+ list_add_tail(&page->buddy_list, &area->free_list[migratetype]);
area->nr_free++;
}
{
struct free_area *area = &zone->free_area[order];
- list_move_tail(&page->lru, &area->free_list[migratetype]);
+ list_move_tail(&page->buddy_list, &area->free_list[migratetype]);
}
static inline void del_page_from_free_list(struct page *page, struct zone *zone,
if (page_reported(page))
__ClearPageReported(page);
- list_del(&page->lru);
+ list_del(&page->buddy_list);
__ClearPageBuddy(page);
set_page_private(page, 0);
zone->free_area[order].nr_free--;
PageSkipKASanPoison(page);
}
-static void kernel_init_free_pages(struct page *page, int numpages)
+static void kernel_init_pages(struct page *page, int numpages)
{
int i;
/* s390's use of memset() could override KASAN redzones. */
kasan_disable_current();
- for (i = 0; i < numpages; i++) {
- u8 tag = page_kasan_tag(page + i);
- page_kasan_tag_reset(page + i);
- clear_highpage(page + i);
- page_kasan_tag_set(page + i, tag);
- }
+ for (i = 0; i < numpages; i++)
+ clear_highpage_kasan_tagged(page + i);
kasan_enable_current();
}
init = false;
}
if (init)
- kernel_init_free_pages(page, 1 << order);
+ kernel_init_pages(page, 1 << order);
/*
* arch_free_page() can make the page's contents inaccessible. s390
/* Ensure requested pindex is drained first. */
pindex = pindex - 1;
- /*
- * local_lock_irq held so equivalent to spin_lock_irqsave for
- * both PREEMPT_RT and non-PREEMPT_RT configurations.
- */
+ /* Caller must hold IRQ-safe pcp->lock so IRQs are disabled. */
spin_lock(&zone->lock);
isolated_pageblocks = has_isolate_pageblock(zone);
do {
int mt;
- page = list_last_entry(list, struct page, lru);
+ page = list_last_entry(list, struct page, pcp_list);
mt = get_pcppage_migratetype(page);
/* must delete to avoid corrupting pcp list */
- list_del(&page->lru);
+ list_del(&page->pcp_list);
count -= nr_pages;
pcp->count -= nr_pages;
}
/* If memory is still not initialized, do it now. */
if (init)
- kernel_init_free_pages(page, 1 << order);
+ kernel_init_pages(page, 1 << order);
/* Propagate __GFP_SKIP_KASAN_POISON to page flags. */
if (kasan_hw_tags_enabled() && (gfp_flags & __GFP_SKIP_KASAN_POISON))
SetPageSkipKASanPoison(page);
{
int i, allocated = 0;
- /*
- * local_lock_irq held so equivalent to spin_lock_irqsave for
- * both PREEMPT_RT and non-PREEMPT_RT configurations.
- */
+ /* Caller must hold IRQ-safe pcp->lock so IRQs are disabled. */
spin_lock(&zone->lock);
for (i = 0; i < count; ++i) {
struct page *page = __rmqueue(zone, order, migratetype,
* for IO devices that can merge IO requests if the physical
* pages are ordered properly.
*/
- list_add_tail(&page->lru, list);
+ list_add_tail(&page->pcp_list, list);
allocated++;
if (is_migrate_cma(get_pcppage_migratetype(page)))
__mod_zone_page_state(zone, NR_FREE_CMA_PAGES,
* Called from the vmstat counter updater to drain pagesets of this
* currently executing processor on remote nodes after they have
* expired.
- *
- * Note that this function must be called with the thread pinned to
- * a single processor.
*/
void drain_zone_pages(struct zone *zone, struct per_cpu_pages *pcp)
{
- unsigned long flags;
int to_drain, batch;
- local_lock_irqsave(&pagesets.lock, flags);
batch = READ_ONCE(pcp->batch);
to_drain = min(pcp->count, batch);
- if (to_drain > 0)
+ if (to_drain > 0) {
+ unsigned long flags;
+
+ /*
+ * free_pcppages_bulk expects IRQs disabled for zone->lock
+ * so even though pcp->lock is not intended to be IRQ-safe,
+ * it's needed in this context.
+ */
+ spin_lock_irqsave(&pcp->lock, flags);
free_pcppages_bulk(zone, to_drain, pcp, 0);
- local_unlock_irqrestore(&pagesets.lock, flags);
+ spin_unlock_irqrestore(&pcp->lock, flags);
+ }
}
#endif
/*
* Drain pcplists of the indicated processor and zone.
- *
- * The processor must either be the current processor and the
- * thread pinned to the current processor or a processor that
- * is not online.
*/
static void drain_pages_zone(unsigned int cpu, struct zone *zone)
{
- unsigned long flags;
struct per_cpu_pages *pcp;
- local_lock_irqsave(&pagesets.lock, flags);
-
pcp = per_cpu_ptr(zone->per_cpu_pageset, cpu);
- if (pcp->count)
- free_pcppages_bulk(zone, pcp->count, pcp, 0);
+ if (pcp->count) {
+ unsigned long flags;
- local_unlock_irqrestore(&pagesets.lock, flags);
+ /* See drain_zone_pages on why this is disabling IRQs */
+ spin_lock_irqsave(&pcp->lock, flags);
+ free_pcppages_bulk(zone, pcp->count, pcp, 0);
+ spin_unlock_irqrestore(&pcp->lock, flags);
+ }
}
/*
* Drain pcplists of all zones on the indicated processor.
- *
- * The processor must either be the current processor and the
- * thread pinned to the current processor or a processor that
- * is not online.
*/
static void drain_pages(unsigned int cpu)
{
/*
* Spill all of this CPU's per-cpu pages back into the buddy allocator.
- *
- * The CPU has to be pinned. When zone parameter is non-NULL, spill just
- * the single zone's pages.
*/
void drain_local_pages(struct zone *zone)
{
drain_pages(cpu);
}
-static void drain_local_pages_wq(struct work_struct *work)
-{
- struct pcpu_drain *drain;
-
- drain = container_of(work, struct pcpu_drain, work);
-
- /*
- * drain_all_pages doesn't use proper cpu hotplug protection so
- * we can race with cpu offline when the WQ can move this from
- * a cpu pinned worker to an unbound one. We can operate on a different
- * cpu which is alright but we also have to make sure to not move to
- * a different one.
- */
- migrate_disable();
- drain_local_pages(drain->zone);
- migrate_enable();
-}
-
/*
* The implementation of drain_all_pages(), exposing an extra parameter to
* drain on all cpus.
static cpumask_t cpus_with_pcps;
/*
- * Make sure nobody triggers this path before mm_percpu_wq is fully
- * initialized.
- */
- if (WARN_ON_ONCE(!mm_percpu_wq))
- return;
-
- /*
* Do not drain if one is already in progress unless it's specific to
* a zone. Such callers are primarily CMA and memory hotplug and need
* the drain to be complete when the call returns.
}
for_each_cpu(cpu, &cpus_with_pcps) {
- struct pcpu_drain *drain = per_cpu_ptr(&pcpu_drain, cpu);
-
- drain->zone = zone;
- INIT_WORK(&drain->work, drain_local_pages_wq);
- queue_work_on(cpu, mm_percpu_wq, &drain->work);
+ if (zone)
+ drain_pages_zone(cpu, zone);
+ else
+ drain_pages(cpu);
}
- for_each_cpu(cpu, &cpus_with_pcps)
- flush_work(&per_cpu_ptr(&pcpu_drain, cpu)->work);
mutex_unlock(&pcpu_drain_mutex);
}
* Spill all the per-cpu pages from all CPUs back into the buddy allocator.
*
* When zone parameter is non-NULL, spill just the single zone's pages.
- *
- * Note that this can be extremely slow as the draining happens in a workqueue.
*/
void drain_all_pages(struct zone *zone)
{
for_each_migratetype_order(order, t) {
list_for_each_entry(page,
- &zone->free_area[order].free_list[t], lru) {
+ &zone->free_area[order].free_list[t], buddy_list) {
unsigned long i;
pfn = page_to_pfn(page);
return min(READ_ONCE(pcp->batch) << 2, high);
}
-static void free_unref_page_commit(struct page *page, int migratetype,
+static void free_unref_page_commit(struct zone *zone, struct per_cpu_pages *pcp,
+ struct page *page, int migratetype,
unsigned int order)
{
- struct zone *zone = page_zone(page);
- struct per_cpu_pages *pcp;
int high;
int pindex;
bool free_high;
__count_vm_event(PGFREE);
- pcp = this_cpu_ptr(zone->per_cpu_pageset);
pindex = order_to_pindex(migratetype, order);
- list_add(&page->lru, &pcp->lists[pindex]);
+ list_add(&page->pcp_list, &pcp->lists[pindex]);
pcp->count += 1 << order;
/*
void free_unref_page(struct page *page, unsigned int order)
{
unsigned long flags;
+ unsigned long __maybe_unused UP_flags;
+ struct per_cpu_pages *pcp;
+ struct zone *zone;
unsigned long pfn = page_to_pfn(page);
int migratetype;
migratetype = MIGRATE_MOVABLE;
}
- local_lock_irqsave(&pagesets.lock, flags);
- free_unref_page_commit(page, migratetype, order);
- local_unlock_irqrestore(&pagesets.lock, flags);
+ zone = page_zone(page);
+ pcp_trylock_prepare(UP_flags);
+ pcp = pcp_spin_trylock_irqsave(zone->per_cpu_pageset, flags);
+ if (pcp) {
+ free_unref_page_commit(zone, pcp, page, migratetype, order);
+ pcp_spin_unlock_irqrestore(pcp, flags);
+ } else {
+ free_one_page(zone, page, pfn, order, migratetype, FPI_NONE);
+ }
+ pcp_trylock_finish(UP_flags);
}
/*
void free_unref_page_list(struct list_head *list)
{
struct page *page, *next;
+ struct per_cpu_pages *pcp = NULL;
+ struct zone *locked_zone = NULL;
unsigned long flags;
int batch_count = 0;
int migratetype;
}
}
- local_lock_irqsave(&pagesets.lock, flags);
list_for_each_entry_safe(page, next, list, lru) {
+ struct zone *zone = page_zone(page);
+
+ /* Different zone, different pcp lock. */
+ if (zone != locked_zone) {
+ if (pcp)
+ pcp_spin_unlock_irqrestore(pcp, flags);
+
+ locked_zone = zone;
+ pcp = pcp_spin_lock_irqsave(locked_zone->per_cpu_pageset, flags);
+ }
+
/*
* Non-isolated types over MIGRATE_PCPTYPES get added
* to the MIGRATE_MOVABLE pcp list.
migratetype = MIGRATE_MOVABLE;
trace_mm_page_free_batched(page);
- free_unref_page_commit(page, migratetype, 0);
+ free_unref_page_commit(zone, pcp, page, migratetype, 0);
/*
* Guard against excessive IRQ disabled times when we get
* a large list of pages to free.
*/
if (++batch_count == SWAP_CLUSTER_MAX) {
- local_unlock_irqrestore(&pagesets.lock, flags);
+ pcp_spin_unlock_irqrestore(pcp, flags);
batch_count = 0;
- local_lock_irqsave(&pagesets.lock, flags);
+ pcp = pcp_spin_lock_irqsave(locked_zone->per_cpu_pageset, flags);
}
}
- local_unlock_irqrestore(&pagesets.lock, flags);
+
+ if (pcp)
+ pcp_spin_unlock_irqrestore(pcp, flags);
}
/*
#endif
}
+static __always_inline
+struct page *rmqueue_buddy(struct zone *preferred_zone, struct zone *zone,
+ unsigned int order, unsigned int alloc_flags,
+ int migratetype)
+{
+ struct page *page;
+ unsigned long flags;
+
+ do {
+ page = NULL;
+ spin_lock_irqsave(&zone->lock, flags);
+ /*
+ * order-0 request can reach here when the pcplist is skipped
+ * due to non-CMA allocation context. HIGHATOMIC area is
+ * reserved for high-order atomic allocation, so order-0
+ * request should skip it.
+ */
+ if (order > 0 && alloc_flags & ALLOC_HARDER)
+ page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC);
+ if (!page) {
+ page = __rmqueue(zone, order, migratetype, alloc_flags);
+ if (!page) {
+ spin_unlock_irqrestore(&zone->lock, flags);
+ return NULL;
+ }
+ }
+ __mod_zone_freepage_state(zone, -(1 << order),
+ get_pcppage_migratetype(page));
+ spin_unlock_irqrestore(&zone->lock, flags);
+ } while (check_new_pages(page, order));
+
+ __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
+ zone_statistics(preferred_zone, zone, 1);
+
+ return page;
+}
+
/* Remove page from the per-cpu list, caller must protect the list */
static inline
struct page *__rmqueue_pcplist(struct zone *zone, unsigned int order,
return NULL;
}
- page = list_first_entry(list, struct page, lru);
- list_del(&page->lru);
+ page = list_first_entry(list, struct page, pcp_list);
+ list_del(&page->pcp_list);
pcp->count -= 1 << order;
} while (check_new_pcp(page, order));
struct list_head *list;
struct page *page;
unsigned long flags;
+ unsigned long __maybe_unused UP_flags;
- local_lock_irqsave(&pagesets.lock, flags);
+ /*
+ * spin_trylock may fail due to a parallel drain. In the future, the
+ * trylock will also protect against IRQ reentrancy.
+ */
+ pcp_trylock_prepare(UP_flags);
+ pcp = pcp_spin_trylock_irqsave(zone->per_cpu_pageset, flags);
+ if (!pcp) {
+ pcp_trylock_finish(UP_flags);
+ return NULL;
+ }
/*
* On allocation, reduce the number of pages that are batch freed.
* See nr_pcp_free() where free_factor is increased for subsequent
* frees.
*/
- pcp = this_cpu_ptr(zone->per_cpu_pageset);
pcp->free_factor >>= 1;
list = &pcp->lists[order_to_pindex(migratetype, order)];
page = __rmqueue_pcplist(zone, order, migratetype, alloc_flags, pcp, list);
- local_unlock_irqrestore(&pagesets.lock, flags);
+ pcp_spin_unlock_irqrestore(pcp, flags);
+ pcp_trylock_finish(UP_flags);
if (page) {
__count_zid_vm_events(PGALLOC, page_zonenum(page), 1);
zone_statistics(preferred_zone, zone, 1);
gfp_t gfp_flags, unsigned int alloc_flags,
int migratetype)
{
- unsigned long flags;
struct page *page;
+ /*
+ * We most definitely don't want callers attempting to
+ * allocate greater than order-1 page units with __GFP_NOFAIL.
+ */
+ WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
+
if (likely(pcp_allowed_order(order))) {
/*
* MIGRATE_MOVABLE pcplist could have the pages on CMA area and
migratetype != MIGRATE_MOVABLE) {
page = rmqueue_pcplist(preferred_zone, zone, order,
gfp_flags, migratetype, alloc_flags);
- goto out;
+ if (likely(page))
+ goto out;
}
}
- /*
- * We most definitely don't want callers attempting to
- * allocate greater than order-1 page units with __GFP_NOFAIL.
- */
- WARN_ON_ONCE((gfp_flags & __GFP_NOFAIL) && (order > 1));
-
- do {
- page = NULL;
- spin_lock_irqsave(&zone->lock, flags);
- /*
- * order-0 request can reach here when the pcplist is skipped
- * due to non-CMA allocation context. HIGHATOMIC area is
- * reserved for high-order atomic allocation, so order-0
- * request should skip it.
- */
- if (order > 0 && alloc_flags & ALLOC_HARDER)
- page = __rmqueue_smallest(zone, order, MIGRATE_HIGHATOMIC);
- if (!page) {
- page = __rmqueue(zone, order, migratetype, alloc_flags);
- if (!page)
- goto failed;
- }
- __mod_zone_freepage_state(zone, -(1 << order),
- get_pcppage_migratetype(page));
- spin_unlock_irqrestore(&zone->lock, flags);
- } while (check_new_pages(page, order));
-
- __count_zid_vm_events(PGALLOC, page_zonenum(page), 1 << order);
- zone_statistics(preferred_zone, zone, 1);
+ page = rmqueue_buddy(preferred_zone, zone, order, alloc_flags,
+ migratetype);
out:
/* Separate test+clear to avoid unnecessary atomics */
- if (test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags)) {
+ if (unlikely(test_bit(ZONE_BOOSTED_WATERMARK, &zone->flags))) {
clear_bit(ZONE_BOOSTED_WATERMARK, &zone->flags);
wakeup_kswapd(zone, 0, 0, zone_idx(zone));
}
VM_BUG_ON_PAGE(page && bad_range(zone, page), page);
return page;
-
-failed:
- spin_unlock_irqrestore(&zone->lock, flags);
- return NULL;
}
#ifdef CONFIG_FAIL_PAGE_ALLOC
retry:
/*
* Scan zonelist, looking for a zone with enough free.
- * See also __cpuset_node_allowed() comment in kernel/cpuset.c.
+ * See also __cpuset_node_allowed() comment in kernel/cgroup/cpuset.c.
*/
no_fallback = alloc_flags & ALLOC_NOFRAGMENT;
z = ac->preferred_zoneref;
EXPORT_SYMBOL_GPL(fs_reclaim_release);
#endif
+/*
+ * Zonelists may change due to hotplug during allocation. Detect when zonelists
+ * have been rebuilt so allocation retries. Reader side does not lock and
+ * retries the allocation if zonelist changes. Writer side is protected by the
+ * embedded spin_lock.
+ */
+static DEFINE_SEQLOCK(zonelist_update_seq);
+
+static unsigned int zonelist_iter_begin(void)
+{
+ if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE))
+ return read_seqbegin(&zonelist_update_seq);
+
+ return 0;
+}
+
+static unsigned int check_retry_zonelist(unsigned int seq)
+{
+ if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE))
+ return read_seqretry(&zonelist_update_seq, seq);
+
+ return seq;
+}
+
/* Perform direct synchronous page reclaim */
static unsigned long
__perform_reclaim(gfp_t gfp_mask, unsigned int order,
int compaction_retries;
int no_progress_loops;
unsigned int cpuset_mems_cookie;
+ unsigned int zonelist_iter_cookie;
int reserve_flags;
/*
(__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)))
gfp_mask &= ~__GFP_ATOMIC;
-retry_cpuset:
+restart:
compaction_retries = 0;
no_progress_loops = 0;
compact_priority = DEF_COMPACT_PRIORITY;
cpuset_mems_cookie = read_mems_allowed_begin();
+ zonelist_iter_cookie = zonelist_iter_begin();
/*
* The fast path uses conservative alloc_flags to succeed only until
goto retry;
- /* Deal with possible cpuset update races before we start OOM killing */
- if (check_retry_cpuset(cpuset_mems_cookie, ac))
- goto retry_cpuset;
+ /*
+ * Deal with possible cpuset update races or zonelist updates to avoid
+ * a unnecessary OOM kill.
+ */
+ if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
+ check_retry_zonelist(zonelist_iter_cookie))
+ goto restart;
/* Reclaim has failed us, start killing things */
page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress);
}
nopage:
- /* Deal with possible cpuset update races before we fail */
- if (check_retry_cpuset(cpuset_mems_cookie, ac))
- goto retry_cpuset;
+ /*
+ * Deal with possible cpuset update races or zonelist updates to avoid
+ * a unnecessary OOM kill.
+ */
+ if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
+ check_retry_zonelist(zonelist_iter_cookie))
+ goto restart;
/*
* Make sure that __GFP_NOFAIL request doesn't leak out and make sure
*alloc_flags |= ALLOC_CPUSET;
}
- fs_reclaim_acquire(gfp_mask);
- fs_reclaim_release(gfp_mask);
-
- might_sleep_if(gfp_mask & __GFP_DIRECT_RECLAIM);
+ might_alloc(gfp_mask);
if (should_fail_alloc_page(gfp_mask, order))
return false;
{
struct page *page;
unsigned long flags;
+ unsigned long __maybe_unused UP_flags;
struct zone *zone;
struct zoneref *z;
struct per_cpu_pages *pcp;
if (unlikely(!zone))
goto failed;
+ /* Is a parallel drain in progress? */
+ pcp_trylock_prepare(UP_flags);
+ pcp = pcp_spin_trylock_irqsave(zone->per_cpu_pageset, flags);
+ if (!pcp)
+ goto failed_irq;
+
/* Attempt the batch allocation */
- local_lock_irqsave(&pagesets.lock, flags);
- pcp = this_cpu_ptr(zone->per_cpu_pageset);
pcp_list = &pcp->lists[order_to_pindex(ac.migratetype, 0)];
-
while (nr_populated < nr_pages) {
/* Skip existing pages */
pcp, pcp_list);
if (unlikely(!page)) {
/* Try and allocate at least one page */
- if (!nr_account)
+ if (!nr_account) {
+ pcp_spin_unlock_irqrestore(pcp, flags);
goto failed_irq;
+ }
break;
}
nr_account++;
nr_populated++;
}
- local_unlock_irqrestore(&pagesets.lock, flags);
+ pcp_spin_unlock_irqrestore(pcp, flags);
+ pcp_trylock_finish(UP_flags);
__count_zid_vm_events(PGALLOC, zone_idx(zone), nr_account);
zone_statistics(ac.preferred_zoneref->zone, zone, nr_account);
return nr_populated;
failed_irq:
- local_unlock_irqrestore(&pagesets.lock, flags);
+ pcp_trylock_finish(UP_flags);
failed:
page = __alloc_pages(gfp, 0, preferred_nid, nodemask);
/* reset page count bias and offset to start of new frag */
nc->pagecnt_bias = PAGE_FRAG_CACHE_MAX_SIZE + 1;
offset = size - fragsz;
+ if (unlikely(offset < 0)) {
+ /*
+ * The caller is trying to allocate a fragment
+ * with fragsz > PAGE_SIZE but the cache isn't big
+ * enough to satisfy the request, this may
+ * happen in low memory conditions.
+ * We don't release the cache page because
+ * it could make memory pressure worse
+ * so we simply return NULL here.
+ */
+ return NULL;
+ }
}
nc->pagecnt_bias--;
/*
* Estimate the amount of memory available for userspace allocations,
- * without causing swapping.
+ * without causing swapping or OOM.
*/
available = global_zone_page_state(NR_FREE_PAGES) - totalreserve_pages;
/*
* Not all the page cache can be freed, otherwise the system will
- * start swapping. Assume at least half of the page cache, or the
- * low watermark worth of cache, needs to stay.
+ * start swapping or thrashing. Assume at least half of the page
+ * cache, or the low watermark worth of cache, needs to stay.
*/
pagecache = pages[LRU_ACTIVE_FILE] + pages[LRU_INACTIVE_FILE];
pagecache -= min(pagecache / 2, wmark_low);
void show_free_areas(unsigned int filter, nodemask_t *nodemask)
{
unsigned long free_pcp = 0;
- int cpu;
+ int cpu, nid;
struct zone *zone;
pg_data_t *pgdat;
printk(KERN_CONT "= %lukB\n", K(total));
}
- hugetlb_show_meminfo();
+ for_each_online_node(nid) {
+ if (show_mem_node_skip(filter, nid, nodemask))
+ continue;
+ hugetlb_show_meminfo_node(nid);
+ }
printk("%ld total pagecache pages\n", global_node_page_state(NR_FILE_PAGES));
int nid;
int __maybe_unused cpu;
pg_data_t *self = data;
- static DEFINE_SPINLOCK(lock);
- spin_lock(&lock);
+ write_seqlock(&zonelist_update_seq);
#ifdef CONFIG_NUMA
memset(node_load, 0, sizeof(node_load));
#endif
}
- spin_unlock(&lock);
+ write_sequnlock(&zonelist_update_seq);
}
static noinline void __init
memset(pcp, 0, sizeof(*pcp));
memset(pzstats, 0, sizeof(*pzstats));
+ spin_lock_init(&pcp->lock);
for (pindex = 0; pindex < NR_PCP_LISTS; pindex++)
INIT_LIST_HEAD(&pcp->lists[pindex]);
projects / platform / kernel / linux-starfive.git / blobdiff