Commit e780149b authored by Xishi Qiu's avatar Xishi Qiu Committed by Linus Torvalds
Browse files

mm: fix set pageblock migratetype in deferred struct page init 

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 freeing the last block in deferred_init_memmap(), it
causes memory leak.

Fixes: ac5d2539 ("mm: meminit: reduce number of times pageblocks are set during struct page init")
Link: http://lkml.kernel.org/r/57A3260F.4050709@huawei.com


Signed-off-by: default avatarXishi Qiu <qiuxishi@huawei.com>
Cc: Taku Izumi <izumi.taku@jp.fujitsu.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: "Kirill A . Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Kamezawa Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent e506b996

mm/page_alloc.c

+13 −7
Original line number Diff line number Diff line
@@ -1393,16 +1393,19 @@ 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 */

static atomic_t pgdat_init_n_undone __initdata;
@@ -1469,9 +1472,9 @@ 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;
@@ -1484,7 +1487,7 @@ 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;
@@ -1520,6 +1523,9 @@ 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);

	}

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