summaryrefslogtreecommitdiff
path: root/mm/page_alloc.c
diff options
context:
space:
mode:
Diffstat (limited to 'mm/page_alloc.c')
-rw-r--r--mm/page_alloc.c17
1 files changed, 16 insertions, 1 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 298c7691fb1d..e80858f5c2ab 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -6596,6 +6596,21 @@ static void __ref __init_zone_device_page(struct page *page, unsigned long pfn,
}
}
+/*
+ * With compound page geometry and when struct pages are stored in ram most
+ * tail pages are reused. Consequently, the amount of unique struct pages to
+ * initialize is a lot smaller that the total amount of struct pages being
+ * mapped. This is a paired / mild layering violation with explicit knowledge
+ * of how the sparse_vmemmap internals handle compound pages in the lack
+ * of an altmap. See vmemmap_populate_compound_pages().
+ */
+static inline unsigned long compound_nr_pages(struct vmem_altmap *altmap,
+ unsigned long nr_pages)
+{
+ return is_power_of_2(sizeof(struct page)) &&
+ !altmap ? 2 * (PAGE_SIZE / sizeof(struct page)) : nr_pages;
+}
+
static void __ref memmap_init_compound(struct page *head,
unsigned long head_pfn,
unsigned long zone_idx, int nid,
@@ -6660,7 +6675,7 @@ void __ref memmap_init_zone_device(struct zone *zone,
continue;
memmap_init_compound(page, pfn, zone_idx, nid, pgmap,
- pfns_per_compound);
+ compound_nr_pages(altmap, pfns_per_compound));
}
pr_info("%s initialised %lu pages in %ums\n", __func__,