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-rw-r--r--mm/page_alloc.c443
1 files changed, 287 insertions, 156 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index d312ebaa1e77..fcc32737f451 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1,6 +1,5 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * linux/mm/page_alloc.c
*
* Manages the free list, the system allocates free pages here.
* Note that kmalloc() lives in slab.c
@@ -1340,8 +1339,8 @@ static inline void pgalloc_tag_sub_pages(struct alloc_tag *tag, unsigned int nr)
#endif /* CONFIG_MEM_ALLOC_PROFILING */
-__always_inline bool free_pages_prepare(struct page *page,
- unsigned int order)
+__always_inline bool __free_pages_prepare(struct page *page,
+ unsigned int order, fpi_t fpi_flags)
{
int bad = 0;
bool skip_kasan_poison = should_skip_kasan_poison(page);
@@ -1430,11 +1429,12 @@ __always_inline bool free_pages_prepare(struct page *page,
page_cpupid_reset_last(page);
page->flags.f &= ~PAGE_FLAGS_CHECK_AT_PREP;
+ page->private = 0;
reset_page_owner(page, order);
page_table_check_free(page, order);
pgalloc_tag_sub(page, 1 << order);
- if (!PageHighMem(page)) {
+ if (!PageHighMem(page) && !(fpi_flags & FPI_TRYLOCK)) {
debug_check_no_locks_freed(page_address(page),
PAGE_SIZE << order);
debug_check_no_obj_freed(page_address(page),
@@ -1473,6 +1473,11 @@ __always_inline bool free_pages_prepare(struct page *page,
return true;
}
+bool free_pages_prepare(struct page *page, unsigned int order)
+{
+ return __free_pages_prepare(page, order, FPI_NONE);
+}
+
/*
* Frees a number of pages from the PCP lists
* Assumes all pages on list are in same zone.
@@ -1606,7 +1611,7 @@ static void __free_pages_ok(struct page *page, unsigned int order,
unsigned long pfn = page_to_pfn(page);
struct zone *zone = page_zone(page);
- if (free_pages_prepare(page, order))
+ if (__free_pages_prepare(page, order, fpi_flags))
free_one_page(zone, page, pfn, order, fpi_flags);
}
@@ -1853,7 +1858,7 @@ inline void post_alloc_hook(struct page *page, unsigned int order,
/*
* As memory initialization might be integrated into KASAN,
- * KASAN unpoisoning and memory initializion code must be
+ * KASAN unpoisoning and memory initialization code must be
* kept together to avoid discrepancies in behavior.
*/
@@ -2946,9 +2951,9 @@ static bool free_frozen_page_commit(struct zone *zone,
* 'hopeless node' to stay in that state for a while. Let
* kswapd work again by resetting kswapd_failures.
*/
- if (atomic_read(&pgdat->kswapd_failures) >= MAX_RECLAIM_RETRIES &&
+ if (kswapd_test_hopeless(pgdat) &&
next_memory_node(pgdat->node_id) < MAX_NUMNODES)
- atomic_set(&pgdat->kswapd_failures, 0);
+ kswapd_clear_hopeless(pgdat, KSWAPD_CLEAR_HOPELESS_PCP);
}
return ret;
}
@@ -2970,7 +2975,7 @@ static void __free_frozen_pages(struct page *page, unsigned int order,
return;
}
- if (!free_pages_prepare(page, order))
+ if (!__free_pages_prepare(page, order, fpi_flags))
return;
/*
@@ -3032,7 +3037,7 @@ void free_unref_folios(struct folio_batch *folios)
unsigned long pfn = folio_pfn(folio);
unsigned int order = folio_order(folio);
- if (!free_pages_prepare(&folio->page, order))
+ if (!__free_pages_prepare(&folio->page, order, FPI_NONE))
continue;
/*
* Free orders not handled on the PCP directly to the
@@ -3112,6 +3117,15 @@ void free_unref_folios(struct folio_batch *folios)
folio_batch_reinit(folios);
}
+static void __split_page(struct page *page, unsigned int order)
+{
+ VM_WARN_ON_PAGE(PageCompound(page), page);
+
+ split_page_owner(page, order, 0);
+ pgalloc_tag_split(page_folio(page), order, 0);
+ split_page_memcg(page, order);
+}
+
/*
* split_page takes a non-compound higher-order page, and splits it into
* n (1<<order) sub-pages: page[0..n]
@@ -3124,14 +3138,12 @@ void split_page(struct page *page, unsigned int order)
{
int i;
- VM_BUG_ON_PAGE(PageCompound(page), page);
- VM_BUG_ON_PAGE(!page_count(page), page);
+ VM_WARN_ON_PAGE(!page_count(page), page);
for (i = 1; i < (1 << order); i++)
set_page_refcounted(page + i);
- split_page_owner(page, order, 0);
- pgalloc_tag_split(page_folio(page), order, 0);
- split_page_memcg(page, order);
+
+ __split_page(page, order);
}
EXPORT_SYMBOL_GPL(split_page);
@@ -4699,7 +4711,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
struct alloc_context *ac)
{
bool can_direct_reclaim = gfp_mask & __GFP_DIRECT_RECLAIM;
- bool can_compact = gfp_compaction_allowed(gfp_mask);
+ bool can_compact = can_direct_reclaim && gfp_compaction_allowed(gfp_mask);
bool nofail = gfp_mask & __GFP_NOFAIL;
const bool costly_order = order > PAGE_ALLOC_COSTLY_ORDER;
struct page *page = NULL;
@@ -4712,6 +4724,8 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
unsigned int cpuset_mems_cookie;
unsigned int zonelist_iter_cookie;
int reserve_flags;
+ bool compact_first = false;
+ bool can_retry_reserves = true;
if (unlikely(nofail)) {
/*
@@ -4736,6 +4750,19 @@ restart:
zonelist_iter_cookie = zonelist_iter_begin();
/*
+ * For costly allocations, try direct compaction first, as it's likely
+ * that we have enough base pages and don't need to reclaim. For non-
+ * movable high-order allocations, do that as well, as compaction will
+ * try prevent permanent fragmentation by migrating from blocks of the
+ * same migratetype.
+ */
+ if (can_compact && (costly_order || (order > 0 &&
+ ac->migratetype != MIGRATE_MOVABLE))) {
+ compact_first = true;
+ compact_priority = INIT_COMPACT_PRIORITY;
+ }
+
+ /*
* The fast path uses conservative alloc_flags to succeed only until
* kswapd needs to be woken up, and to avoid the cost of setting up
* alloc_flags precisely. So we do that now.
@@ -4766,6 +4793,8 @@ restart:
goto nopage;
}
+retry:
+ /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */
if (alloc_flags & ALLOC_KSWAPD)
wake_all_kswapds(order, gfp_mask, ac);
@@ -4777,74 +4806,6 @@ restart:
if (page)
goto got_pg;
- /*
- * For costly allocations, try direct compaction first, as it's likely
- * that we have enough base pages and don't need to reclaim. For non-
- * movable high-order allocations, do that as well, as compaction will
- * try prevent permanent fragmentation by migrating from blocks of the
- * same migratetype.
- * Don't try this for allocations that are allowed to ignore
- * watermarks, as the ALLOC_NO_WATERMARKS attempt didn't yet happen.
- */
- if (can_direct_reclaim && can_compact &&
- (costly_order ||
- (order > 0 && ac->migratetype != MIGRATE_MOVABLE))
- && !gfp_pfmemalloc_allowed(gfp_mask)) {
- page = __alloc_pages_direct_compact(gfp_mask, order,
- alloc_flags, ac,
- INIT_COMPACT_PRIORITY,
- &compact_result);
- if (page)
- goto got_pg;
-
- /*
- * Checks for costly allocations with __GFP_NORETRY, which
- * includes some THP page fault allocations
- */
- if (costly_order && (gfp_mask & __GFP_NORETRY)) {
- /*
- * If allocating entire pageblock(s) and compaction
- * failed because all zones are below low watermarks
- * or is prohibited because it recently failed at this
- * order, fail immediately unless the allocator has
- * requested compaction and reclaim retry.
- *
- * Reclaim is
- * - potentially very expensive because zones are far
- * below their low watermarks or this is part of very
- * bursty high order allocations,
- * - not guaranteed to help because isolate_freepages()
- * may not iterate over freed pages as part of its
- * linear scan, and
- * - unlikely to make entire pageblocks free on its
- * own.
- */
- if (compact_result == COMPACT_SKIPPED ||
- compact_result == COMPACT_DEFERRED)
- goto nopage;
-
- /*
- * Looks like reclaim/compaction is worth trying, but
- * sync compaction could be very expensive, so keep
- * using async compaction.
- */
- compact_priority = INIT_COMPACT_PRIORITY;
- }
- }
-
-retry:
- /*
- * Deal with possible cpuset update races or zonelist updates to avoid
- * infinite retries.
- */
- if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
- check_retry_zonelist(zonelist_iter_cookie))
- goto restart;
-
- /* Ensure kswapd doesn't accidentally go to sleep as long as we loop */
- if (alloc_flags & ALLOC_KSWAPD)
- wake_all_kswapds(order, gfp_mask, ac);
-
reserve_flags = __gfp_pfmemalloc_flags(gfp_mask);
if (reserve_flags)
alloc_flags = gfp_to_alloc_flags_cma(gfp_mask, reserve_flags) |
@@ -4859,12 +4820,18 @@ retry:
ac->nodemask = NULL;
ac->preferred_zoneref = first_zones_zonelist(ac->zonelist,
ac->highest_zoneidx, ac->nodemask);
- }
- /* Attempt with potentially adjusted zonelist and alloc_flags */
- page = get_page_from_freelist(gfp_mask, order, alloc_flags, ac);
- if (page)
- goto got_pg;
+ /*
+ * The first time we adjust anything due to being allowed to
+ * ignore memory policies or watermarks, retry immediately. This
+ * allows us to keep the first allocation attempt optimistic so
+ * it can succeed in a zone that is still above watermarks.
+ */
+ if (can_retry_reserves) {
+ can_retry_reserves = false;
+ goto retry;
+ }
+ }
/* Caller is not willing to reclaim, we can't balance anything */
if (!can_direct_reclaim)
@@ -4875,10 +4842,12 @@ retry:
goto nopage;
/* Try direct reclaim and then allocating */
- page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags, ac,
- &did_some_progress);
- if (page)
- goto got_pg;
+ if (!compact_first) {
+ page = __alloc_pages_direct_reclaim(gfp_mask, order, alloc_flags,
+ ac, &did_some_progress);
+ if (page)
+ goto got_pg;
+ }
/* Try direct compaction and then allocating */
page = __alloc_pages_direct_compact(gfp_mask, order, alloc_flags, ac,
@@ -4886,6 +4855,33 @@ retry:
if (page)
goto got_pg;
+ if (compact_first) {
+ /*
+ * THP page faults may attempt local node only first, but are
+ * then allowed to only compact, not reclaim, see
+ * alloc_pages_mpol().
+ *
+ * Compaction has failed above and we don't want such THP
+ * allocations to put reclaim pressure on a single node in a
+ * situation where other nodes might have plenty of available
+ * memory.
+ */
+ if (gfp_has_flags(gfp_mask, __GFP_NORETRY | __GFP_THISNODE))
+ goto nopage;
+
+ /*
+ * For the initial compaction attempt we have lowered its
+ * priority. Restore it for further retries, if those are
+ * allowed. With __GFP_NORETRY there will be a single round of
+ * reclaim and compaction with the lowered priority.
+ */
+ if (!(gfp_mask & __GFP_NORETRY))
+ compact_priority = DEF_COMPACT_PRIORITY;
+
+ compact_first = false;
+ goto retry;
+ }
+
/* Do not loop if specifically requested */
if (gfp_mask & __GFP_NORETRY)
goto nopage;
@@ -4898,6 +4894,15 @@ retry:
!(gfp_mask & __GFP_RETRY_MAYFAIL)))
goto nopage;
+ /*
+ * Deal with possible cpuset update races or zonelist updates to avoid
+ * infinite retries. No "goto retry;" can be placed above this check
+ * unless it can execute just once.
+ */
+ if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
+ check_retry_zonelist(zonelist_iter_cookie))
+ goto restart;
+
if (should_reclaim_retry(gfp_mask, order, ac, alloc_flags,
did_some_progress > 0, &no_progress_loops))
goto retry;
@@ -5401,9 +5406,7 @@ static void *make_alloc_exact(unsigned long addr, unsigned int order,
struct page *page = virt_to_page((void *)addr);
struct page *last = page + nr;
- split_page_owner(page, order, 0);
- pgalloc_tag_split(page_folio(page), order, 0);
- split_page_memcg(page, order);
+ __split_page(page, order);
while (page < --last)
set_page_refcounted(last);
@@ -6896,7 +6899,7 @@ static int __alloc_contig_migrate_range(struct compact_control *cc,
return (ret < 0) ? ret : 0;
}
-static void split_free_pages(struct list_head *list, gfp_t gfp_mask)
+static void split_free_frozen_pages(struct list_head *list, gfp_t gfp_mask)
{
int order;
@@ -6908,11 +6911,10 @@ static void split_free_pages(struct list_head *list, gfp_t gfp_mask)
int i;
post_alloc_hook(page, order, gfp_mask);
- set_page_refcounted(page);
if (!order)
continue;
- split_page(page, order);
+ __split_page(page, order);
/* Add all subpages to the order-0 head, in sequence. */
list_del(&page->lru);
@@ -6956,8 +6958,14 @@ static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask)
return 0;
}
+static void __free_contig_frozen_range(unsigned long pfn, unsigned long nr_pages)
+{
+ for (; nr_pages--; pfn++)
+ free_frozen_pages(pfn_to_page(pfn), 0);
+}
+
/**
- * alloc_contig_range() -- tries to allocate given range of pages
+ * alloc_contig_frozen_range() -- tries to allocate given range of frozen pages
* @start: start PFN to allocate
* @end: one-past-the-last PFN to allocate
* @alloc_flags: allocation information
@@ -6972,12 +6980,15 @@ static int __alloc_contig_verify_gfp_mask(gfp_t gfp_mask, gfp_t *gfp_cc_mask)
* pageblocks in the range. Once isolated, the pageblocks should not
* be modified by others.
*
- * Return: zero on success or negative error code. On success all
- * pages which PFN is in [start, end) are allocated for the caller and
- * need to be freed with free_contig_range().
+ * All frozen pages which PFN is in [start, end) are allocated for the
+ * caller, and they could be freed with free_contig_frozen_range(),
+ * free_frozen_pages() also could be used to free compound frozen pages
+ * directly.
+ *
+ * Return: zero on success or negative error code.
*/
-int alloc_contig_range_noprof(unsigned long start, unsigned long end,
- acr_flags_t alloc_flags, gfp_t gfp_mask)
+int alloc_contig_frozen_range_noprof(unsigned long start, unsigned long end,
+ acr_flags_t alloc_flags, gfp_t gfp_mask)
{
const unsigned int order = ilog2(end - start);
unsigned long outer_start, outer_end;
@@ -7093,19 +7104,18 @@ int alloc_contig_range_noprof(unsigned long start, unsigned long end,
}
if (!(gfp_mask & __GFP_COMP)) {
- split_free_pages(cc.freepages, gfp_mask);
+ split_free_frozen_pages(cc.freepages, gfp_mask);
/* Free head and tail (if any) */
if (start != outer_start)
- free_contig_range(outer_start, start - outer_start);
+ __free_contig_frozen_range(outer_start, start - outer_start);
if (end != outer_end)
- free_contig_range(end, outer_end - end);
+ __free_contig_frozen_range(end, outer_end - end);
} else if (start == outer_start && end == outer_end && is_power_of_2(end - start)) {
struct page *head = pfn_to_page(start);
check_new_pages(head, order);
prep_new_page(head, order, gfp_mask, 0);
- set_page_refcounted(head);
} else {
ret = -EINVAL;
WARN(true, "PFN range: requested [%lu, %lu), allocated [%lu, %lu)\n",
@@ -7115,36 +7125,86 @@ done:
undo_isolate_page_range(start, end);
return ret;
}
-EXPORT_SYMBOL(alloc_contig_range_noprof);
+EXPORT_SYMBOL(alloc_contig_frozen_range_noprof);
-static int __alloc_contig_pages(unsigned long start_pfn,
- unsigned long nr_pages, gfp_t gfp_mask)
+/**
+ * alloc_contig_range() -- tries to allocate given range of pages
+ * @start: start PFN to allocate
+ * @end: one-past-the-last PFN to allocate
+ * @alloc_flags: allocation information
+ * @gfp_mask: GFP mask.
+ *
+ * This routine is a wrapper around alloc_contig_frozen_range(), it can't
+ * be used to allocate compound pages, the refcount of each allocated page
+ * will be set to one.
+ *
+ * All pages which PFN is in [start, end) are allocated for the caller,
+ * and should be freed with free_contig_range() or by manually calling
+ * __free_page() on each allocated page.
+ *
+ * Return: zero on success or negative error code.
+ */
+int alloc_contig_range_noprof(unsigned long start, unsigned long end,
+ acr_flags_t alloc_flags, gfp_t gfp_mask)
{
- unsigned long end_pfn = start_pfn + nr_pages;
+ int ret;
+
+ if (WARN_ON(gfp_mask & __GFP_COMP))
+ return -EINVAL;
- return alloc_contig_range_noprof(start_pfn, end_pfn, ACR_FLAGS_NONE,
- gfp_mask);
+ ret = alloc_contig_frozen_range_noprof(start, end, alloc_flags, gfp_mask);
+ if (!ret)
+ set_pages_refcounted(pfn_to_page(start), end - start);
+
+ return ret;
}
+EXPORT_SYMBOL(alloc_contig_range_noprof);
static bool pfn_range_valid_contig(struct zone *z, unsigned long start_pfn,
- unsigned long nr_pages)
+ unsigned long nr_pages, bool skip_hugetlb,
+ bool *skipped_hugetlb)
{
- unsigned long i, end_pfn = start_pfn + nr_pages;
+ unsigned long end_pfn = start_pfn + nr_pages;
struct page *page;
- for (i = start_pfn; i < end_pfn; i++) {
- page = pfn_to_online_page(i);
+ while (start_pfn < end_pfn) {
+ unsigned long step = 1;
+
+ page = pfn_to_online_page(start_pfn);
if (!page)
return false;
if (page_zone(page) != z)
return false;
- if (PageReserved(page))
+ if (page_is_unmovable(z, page, PB_ISOLATE_MODE_OTHER, &step))
return false;
- if (PageHuge(page))
- return false;
+ /*
+ * Only consider ranges containing hugepages if those pages are
+ * smaller than the requested contiguous region. e.g.:
+ * Move 2MB pages to free up a 1GB range.
+ * Don't move 1GB pages to free up a 2MB range.
+ *
+ * This makes contiguous allocation more reliable if multiple
+ * hugepage sizes are used without causing needless movement.
+ */
+ if (PageHuge(page)) {
+ unsigned int order;
+
+ if (skip_hugetlb) {
+ *skipped_hugetlb = true;
+ return false;
+ }
+
+ page = compound_head(page);
+ order = compound_order(page);
+ if ((order >= MAX_FOLIO_ORDER) ||
+ (nr_pages <= (1 << order)))
+ return false;
+ }
+
+ start_pfn += step;
}
return true;
}
@@ -7158,7 +7218,7 @@ static bool zone_spans_last_pfn(const struct zone *zone,
}
/**
- * alloc_contig_pages() -- tries to find and allocate contiguous range of pages
+ * alloc_contig_frozen_pages() -- tries to find and allocate contiguous range of frozen pages
* @nr_pages: Number of contiguous pages to allocate
* @gfp_mask: GFP mask. Node/zone/placement hints limit the search; only some
* action and reclaim modifiers are supported. Reclaim modifiers
@@ -7166,28 +7226,34 @@ static bool zone_spans_last_pfn(const struct zone *zone,
* @nid: Target node
* @nodemask: Mask for other possible nodes
*
- * This routine is a wrapper around alloc_contig_range(). It scans over zones
- * on an applicable zonelist to find a contiguous pfn range which can then be
- * tried for allocation with alloc_contig_range(). This routine is intended
- * for allocation requests which can not be fulfilled with the buddy allocator.
+ * This routine is a wrapper around alloc_contig_frozen_range(). It scans over
+ * zones on an applicable zonelist to find a contiguous pfn range which can then
+ * be tried for allocation with alloc_contig_frozen_range(). This routine is
+ * intended for allocation requests which can not be fulfilled with the buddy
+ * allocator.
*
* The allocated memory is always aligned to a page boundary. If nr_pages is a
* power of two, then allocated range is also guaranteed to be aligned to same
* nr_pages (e.g. 1GB request would be aligned to 1GB).
*
- * Allocated pages can be freed with free_contig_range() or by manually calling
- * __free_page() on each allocated page.
+ * Allocated frozen pages need be freed with free_contig_frozen_range(),
+ * or by manually calling free_frozen_pages() on each allocated frozen
+ * non-compound page, for compound frozen pages could be freed with
+ * free_frozen_pages() directly.
*
- * Return: pointer to contiguous pages on success, or NULL if not successful.
+ * Return: pointer to contiguous frozen pages on success, or NULL if not successful.
*/
-struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
- int nid, nodemask_t *nodemask)
+struct page *alloc_contig_frozen_pages_noprof(unsigned long nr_pages,
+ gfp_t gfp_mask, int nid, nodemask_t *nodemask)
{
unsigned long ret, pfn, flags;
struct zonelist *zonelist;
struct zone *zone;
struct zoneref *z;
+ bool skip_hugetlb = true;
+ bool skipped_hugetlb = false;
+retry:
zonelist = node_zonelist(nid, gfp_mask);
for_each_zone_zonelist_nodemask(zone, z, zonelist,
gfp_zone(gfp_mask), nodemask) {
@@ -7195,16 +7261,20 @@ struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
pfn = ALIGN(zone->zone_start_pfn, nr_pages);
while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
- if (pfn_range_valid_contig(zone, pfn, nr_pages)) {
+ if (pfn_range_valid_contig(zone, pfn, nr_pages,
+ skip_hugetlb,
+ &skipped_hugetlb)) {
/*
* We release the zone lock here because
- * alloc_contig_range() will also lock the zone
- * at some point. If there's an allocation
- * spinning on this lock, it may win the race
- * and cause alloc_contig_range() to fail...
+ * alloc_contig_frozen_range() will also lock
+ * the zone at some point. If there's an
+ * allocation spinning on this lock, it may
+ * win the race and cause allocation to fail.
*/
spin_unlock_irqrestore(&zone->lock, flags);
- ret = __alloc_contig_pages(pfn, nr_pages,
+ ret = alloc_contig_frozen_range_noprof(pfn,
+ pfn + nr_pages,
+ ACR_FLAGS_NONE,
gfp_mask);
if (!ret)
return pfn_to_page(pfn);
@@ -7214,35 +7284,96 @@ struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
}
spin_unlock_irqrestore(&zone->lock, flags);
}
+ /*
+ * If we failed, retry the search, but treat regions with HugeTLB pages
+ * as valid targets. This retains fast-allocations on first pass
+ * without trying to migrate HugeTLB pages (which may fail). On the
+ * second pass, we will try moving HugeTLB pages when those pages are
+ * smaller than the requested contiguous region size.
+ */
+ if (skip_hugetlb && skipped_hugetlb) {
+ skip_hugetlb = false;
+ goto retry;
+ }
return NULL;
}
-#endif /* CONFIG_CONTIG_ALLOC */
+EXPORT_SYMBOL(alloc_contig_frozen_pages_noprof);
-void free_contig_range(unsigned long pfn, unsigned long nr_pages)
+/**
+ * alloc_contig_pages() -- tries to find and allocate contiguous range of pages
+ * @nr_pages: Number of contiguous pages to allocate
+ * @gfp_mask: GFP mask.
+ * @nid: Target node
+ * @nodemask: Mask for other possible nodes
+ *
+ * This routine is a wrapper around alloc_contig_frozen_pages(), it can't
+ * be used to allocate compound pages, the refcount of each allocated page
+ * will be set to one.
+ *
+ * Allocated pages can be freed with free_contig_range() or by manually
+ * calling __free_page() on each allocated page.
+ *
+ * Return: pointer to contiguous pages on success, or NULL if not successful.
+ */
+struct page *alloc_contig_pages_noprof(unsigned long nr_pages, gfp_t gfp_mask,
+ int nid, nodemask_t *nodemask)
{
- unsigned long count = 0;
- struct folio *folio = pfn_folio(pfn);
+ struct page *page;
- if (folio_test_large(folio)) {
- int expected = folio_nr_pages(folio);
+ if (WARN_ON(gfp_mask & __GFP_COMP))
+ return NULL;
- if (nr_pages == expected)
- folio_put(folio);
- else
- WARN(true, "PFN %lu: nr_pages %lu != expected %d\n",
- pfn, nr_pages, expected);
+ page = alloc_contig_frozen_pages_noprof(nr_pages, gfp_mask, nid,
+ nodemask);
+ if (page)
+ set_pages_refcounted(page, nr_pages);
+
+ return page;
+}
+EXPORT_SYMBOL(alloc_contig_pages_noprof);
+
+/**
+ * free_contig_frozen_range() -- free the contiguous range of frozen pages
+ * @pfn: start PFN to free
+ * @nr_pages: Number of contiguous frozen pages to free
+ *
+ * This can be used to free the allocated compound/non-compound frozen pages.
+ */
+void free_contig_frozen_range(unsigned long pfn, unsigned long nr_pages)
+{
+ struct page *first_page = pfn_to_page(pfn);
+ const unsigned int order = ilog2(nr_pages);
+
+ if (WARN_ON_ONCE(first_page != compound_head(first_page)))
+ return;
+
+ if (PageHead(first_page)) {
+ WARN_ON_ONCE(order != compound_order(first_page));
+ free_frozen_pages(first_page, order);
return;
}
- for (; nr_pages--; pfn++) {
- struct page *page = pfn_to_page(pfn);
+ __free_contig_frozen_range(pfn, nr_pages);
+}
+EXPORT_SYMBOL(free_contig_frozen_range);
- count += page_count(page) != 1;
- __free_page(page);
- }
- WARN(count != 0, "%lu pages are still in use!\n", count);
+/**
+ * free_contig_range() -- free the contiguous range of pages
+ * @pfn: start PFN to free
+ * @nr_pages: Number of contiguous pages to free
+ *
+ * This can be only used to free the allocated non-compound pages.
+ */
+void free_contig_range(unsigned long pfn, unsigned long nr_pages)
+{
+ if (WARN_ON_ONCE(PageHead(pfn_to_page(pfn))))
+ return;
+
+ for (; nr_pages--; pfn++)
+ __free_page(pfn_to_page(pfn));
}
EXPORT_SYMBOL(free_contig_range);
+#endif /* CONFIG_CONTIG_ALLOC */
/*
* Effectively disable pcplists for the zone by setting the high limit to 0
@@ -7658,7 +7789,7 @@ struct page *alloc_frozen_pages_nolock_noprof(gfp_t gfp_flags, int nid, unsigned
* unsafe in NMI. If spin_trylock() is called from hard IRQ the current
* task may be waiting for one rt_spin_lock, but rt_spin_trylock() will
* mark the task as the owner of another rt_spin_lock which will
- * confuse PI logic, so return immediately if called form hard IRQ or
+ * confuse PI logic, so return immediately if called from hard IRQ or
* NMI.
*
* Note, irqs_disabled() case is ok. This function can be called