Fixes: ac5d2539b238 ("mm: meminit: reduce number of times pageblocks are set during struct page init")
and stable 4.2+
on x86_64 MAX_ORDER_NR_PAGES is usually 4M, and a pageblock is usually 2M,
so we only set one pageblock's migratetype in deferred_free_range() if pfn
is aligned to MAX_ORDER_NR_PAGES. That means it causes uninitialized migratetype
blocks, you can see from "cat /proc/pagetypeinfo", almost half blocks are
Unmovable.
Also we missed to free the last block in deferred_init_memmap(), it causes
memory leak.
Signed-off-by: Xishi Qiu <qiuxishi@xxxxxxxxxx>
---
mm/page_alloc.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 2b258ec..e0ec3b6 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -1399,15 +1399,18 @@ static void __init deferred_free_range(struct page *page,
return;
/* Free a large naturally-aligned chunk if possible */
- if (nr_pages == MAX_ORDER_NR_PAGES &&
- (pfn & (MAX_ORDER_NR_PAGES-1)) == 0) {
+ if (nr_pages == pageblock_nr_pages &&
+ (pfn & (pageblock_nr_pages - 1)) == 0) {
set_pageblock_migratetype(page, MIGRATE_MOVABLE);
- __free_pages_boot_core(page, MAX_ORDER-1);
+ __free_pages_boot_core(page, pageblock_order);
return;
}
- for (i = 0; i < nr_pages; i++, page++)
+ for (i = 0; i < nr_pages; i++, page++, pfn++) {
+ if ((pfn & (pageblock_nr_pages - 1)) == 0)
+ set_pageblock_migratetype(page, MIGRATE_MOVABLE);
__free_pages_boot_core(page, 0);
+ }
}
/* Completion tracking for deferred_init_memmap() threads */
@@ -1475,9 +1478,9 @@ static int __init deferred_init_memmap(void *data)
/*
* Ensure pfn_valid is checked every
- * MAX_ORDER_NR_PAGES for memory holes
+ * pageblock_nr_pages for memory holes
*/
- if ((pfn & (MAX_ORDER_NR_PAGES - 1)) == 0) {
+ if ((pfn & (pageblock_nr_pages - 1)) == 0) {
if (!pfn_valid(pfn)) {
page = NULL;
goto free_range;
@@ -1490,7 +1493,7 @@ static int __init deferred_init_memmap(void *data)
}
/* Minimise pfn page lookups and scheduler checks */
- if (page && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0) {
+ if (page && (pfn & (pageblock_nr_pages - 1)) != 0) {
page++;
} else {
nr_pages += nr_to_free;
@@ -1526,6 +1529,9 @@ free_range:
free_base_page = NULL;
free_base_pfn = nr_to_free = 0;
}
+ /* Free the last block of pages to allocator */
+ nr_pages += nr_to_free;
+ deferred_free_range(free_base_page, free_base_pfn, nr_to_free);
first_init_pfn = max(end_pfn, first_init_pfn);
}
--
1.8.3.1
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>