alloc_gigantic_page() implements an allocation method where it scans over
various zones looking for a large contiguous memory block which could not
have been allocated through the buddy allocator. A subsequent patch which
tests arch page table helpers needs such a method to allocate PUD_SIZE
sized memory block. In the future such methods might have other use cases
as well. So alloc_gigantic_page() has been split carving out actual memory
allocation method and made available via new alloc_gigantic_page_order()
which is wrapped under CONFIG_CONTIG_ALLOC.
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Steven Price <Steven.Price@xxxxxxx>
Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Sri Krishna chowdary <schowdary@xxxxxxxxxx>
Cc: Dave Hansen <dave.hansen@xxxxxxxxx>
Cc: Russell King - ARM Linux <linux@xxxxxxxxxxxxxxx>
Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Vineet Gupta <vgupta@xxxxxxxxxxxx>
Cc: James Hogan <jhogan@xxxxxxxxxx>
Cc: Paul Burton <paul.burton@xxxxxxxx>
Cc: Ralf Baechle <ralf@xxxxxxxxxxxxxx>
Cc: Kirill A. Shutemov <kirill@xxxxxxxxxxxxx>
Cc: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
Cc: Christophe Leroy <christophe.leroy@xxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Oscar Salvador <osalvador@xxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
Cc: linux-mips@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-ia64@xxxxxxxxxxxxxxx
Cc: linuxppc-dev@xxxxxxxxxxxxxxxx
Cc: linux-s390@xxxxxxxxxxxxxxx
Cc: linux-sh@xxxxxxxxxxxxxxx
Cc: sparclinux@xxxxxxxxxxxxxxx
Cc: x86@xxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
include/linux/gfp.h | 3 ++
mm/hugetlb.c | 76 +----------------------------------
mm/page_alloc.c | 98 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 102 insertions(+), 75 deletions(-)
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index fb07b503dc45..379ad23437d1 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -589,6 +589,9 @@ static inline bool pm_suspended_storage(void)
/* The below functions must be run on a range from a single zone. */
extern int alloc_contig_range(unsigned long start, unsigned long end,
unsigned migratetype, gfp_t gfp_mask);
+extern struct page *alloc_gigantic_page_order(unsigned int order,
+ gfp_t gfp_mask, int nid,
+ nodemask_t *nodemask);
#endif
void free_contig_range(unsigned long pfn, unsigned int nr_pages);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 977f9a323a7a..d199556a4a2c 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -1023,86 +1023,12 @@ static void free_gigantic_page(struct page *page, unsigned int order)
}
#ifdef CONFIG_CONTIG_ALLOC
-static int __alloc_gigantic_page(unsigned long start_pfn,
- unsigned long nr_pages, gfp_t gfp_mask)
-{
- unsigned long end_pfn = start_pfn + nr_pages;
- return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
- gfp_mask);
-}
-
-static bool pfn_range_valid_gigantic(struct zone *z,
- unsigned long start_pfn, unsigned long nr_pages)
-{
- unsigned long i, end_pfn = start_pfn + nr_pages;
- struct page *page;
-
- for (i = start_pfn; i < end_pfn; i++) {
- if (!pfn_valid(i))
- return false;
-
- page = pfn_to_page(i);
-
- if (page_zone(page) != z)
- return false;
-
- if (PageReserved(page))
- return false;
-
- if (page_count(page) > 0)
- return false;
-
- if (PageHuge(page))
- return false;
- }
-
- return true;
-}
-
-static bool zone_spans_last_pfn(const struct zone *zone,
- unsigned long start_pfn, unsigned long nr_pages)
-{
- unsigned long last_pfn = start_pfn + nr_pages - 1;
- return zone_spans_pfn(zone, last_pfn);
-}
-
static struct page *alloc_gigantic_page(struct hstate *h, gfp_t gfp_mask,
int nid, nodemask_t *nodemask)
{
unsigned int order = huge_page_order(h);
- unsigned long nr_pages = 1 << order;
- unsigned long ret, pfn, flags;
- struct zonelist *zonelist;
- struct zone *zone;
- struct zoneref *z;
-
- zonelist = node_zonelist(nid, gfp_mask);
- for_each_zone_zonelist_nodemask(zone, z, zonelist, gfp_zone(gfp_mask), nodemask) {
- spin_lock_irqsave(&zone->lock, flags);
- pfn = ALIGN(zone->zone_start_pfn, nr_pages);
- while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
- if (pfn_range_valid_gigantic(zone, pfn, nr_pages)) {
- /*
- * 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...
- */
- spin_unlock_irqrestore(&zone->lock, flags);
- ret = __alloc_gigantic_page(pfn, nr_pages, gfp_mask);
- if (!ret)
- return pfn_to_page(pfn);
- spin_lock_irqsave(&zone->lock, flags);
- }
- pfn += nr_pages;
- }
-
- spin_unlock_irqrestore(&zone->lock, flags);
- }
-
- return NULL;
+ return alloc_gigantic_page_order(order, gfp_mask, nid, nodemask);
}
static void prep_new_huge_page(struct hstate *h, struct page *page, int nid);
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6ab8eb670fd3..0f67367213c6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -8497,6 +8497,104 @@ int alloc_contig_range(unsigned long start, unsigned long end,
pfn_max_align_up(end), migratetype);
return ret;
}
+
+static int __alloc_gigantic_page(unsigned long start_pfn,
+ unsigned long nr_pages, gfp_t gfp_mask)
+{
+ unsigned long end_pfn = start_pfn + nr_pages;
+
+ return alloc_contig_range(start_pfn, end_pfn, MIGRATE_MOVABLE,
+ gfp_mask);
+}
+
+static bool pfn_range_valid_gigantic(struct zone *z, unsigned long start_pfn,
+ unsigned long nr_pages)
+{
+ unsigned long i, end_pfn = start_pfn + nr_pages;
+ struct page *page;
+
+ for (i = start_pfn; i < end_pfn; i++) {
+ if (!pfn_valid(i))
+ return false;
+
+ page = pfn_to_page(i);
+
+ if (page_zone(page) != z)
+ return false;
+
+ if (PageReserved(page))
+ return false;
+
+ if (page_count(page) > 0)
+ return false;
+
+ if (PageHuge(page))
+ return false;
+ }
+ return true;
+}
+
+static bool zone_spans_last_pfn(const struct zone *zone,
+ unsigned long start_pfn, unsigned long nr_pages)
+{
+ unsigned long last_pfn = start_pfn + nr_pages - 1;
+
+ return zone_spans_pfn(zone, last_pfn);
+}
+
+/**
+ * alloc_gigantic_page_order() -- tries to allocate given order of pages
+ * @order: allocation order (greater than MAX_ORDER)
+ * @gfp_mask: GFP mask to use during compaction
+ * @nid: allocation node
+ * @nodemask: allocation nodemask
+ *
+ * This routine is an wrapper around alloc_contig_range() which scans over
+ * all zones on an applicable zonelist to find a contiguous pfn range which
+ * can the be allocated with alloc_contig_range(). This routine is intended
+ * to be used for allocations greater than MAX_ORDER.
+ *
+ * Return: page on success or NULL on failure. On success a memory block
+ * of 'order' starting with 'page' has been allocated successfully. Memory
+ * allocated here needs to be freed with free_contig_range().
+ */
+struct page *alloc_gigantic_page_order(unsigned int order, gfp_t gfp_mask,
+ int nid, nodemask_t *nodemask)
+{
+ unsigned long nr_pages = 1 << order;
+ unsigned long ret, pfn, flags;
+ struct zonelist *zonelist;
+ struct zone *zone;
+ struct zoneref *z;
+
+ zonelist = node_zonelist(nid, gfp_mask);
+ for_each_zone_zonelist_nodemask(zone, z, zonelist,
+ gfp_zone(gfp_mask), nodemask) {
+ spin_lock_irqsave(&zone->lock, flags);
+
+ pfn = ALIGN(zone->zone_start_pfn, nr_pages);
+ while (zone_spans_last_pfn(zone, pfn, nr_pages)) {
+ if (pfn_range_valid_gigantic(zone, pfn, nr_pages)) {
+ /*
+ * 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...
+ */
+ spin_unlock_irqrestore(&zone->lock, flags);
+ ret = __alloc_gigantic_page(pfn, nr_pages,
+ gfp_mask);
+ if (!ret)
+ return pfn_to_page(pfn);
+ spin_lock_irqsave(&zone->lock, flags);
+ }
+ pfn += nr_pages;
+ }
+ spin_unlock_irqrestore(&zone->lock, flags);
+ }
+ return NULL;
+}
#endif /* CONFIG_CONTIG_ALLOC */
void free_contig_range(unsigned long pfn, unsigned int nr_pages)
--
2.20.1
_______________________________________________
linux-snps-arc mailing list
linux-snps-arc@xxxxxxxxxxxxxxxxxxx
http://lists.infradead.org/mailman/listinfo/linux-snps-arc
