Commit 6e263fff authored by Zi Yan's avatar Zi Yan Committed by Andrew Morton
Browse files

mm: page_isolation: enable arbitrary range page isolation. 

Now start_isolate_page_range() is ready to handle arbitrary range
isolation, so move the alignment check/adjustment into the function body. 
Do the same for its counterpart undo_isolate_page_range(). 
alloc_contig_range(), its caller, can pass an arbitrary range instead of a
MAX_ORDER_NR_PAGES aligned one.

Link: https://lkml.kernel.org/r/20220425143118.2850746-5-zi.yan@sent.com


Signed-off-by: default avatarZi Yan <ziy@nvidia.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Hildenbrand <david@redhat.com>
Cc: Eric Ren <renzhengeek@gmail.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent b2c9e2fb

mm/page_alloc.c

+2 −14
Original line number Diff line number Diff line
@@ -8956,16 +8956,6 @@ void *__init alloc_large_system_hash(const char *tablename, 
}



#ifdef CONFIG_CONTIG_ALLOC

static unsigned long pfn_max_align_down(unsigned long pfn)

{

	return ALIGN_DOWN(pfn, MAX_ORDER_NR_PAGES);

}



static unsigned long pfn_max_align_up(unsigned long pfn)

{

	return ALIGN(pfn, MAX_ORDER_NR_PAGES);

}



#if defined(CONFIG_DYNAMIC_DEBUG) || \

	(defined(CONFIG_DYNAMIC_DEBUG_CORE) && defined(DYNAMIC_DEBUG_MODULE))

/* Usage: See admin-guide/dynamic-debug-howto.rst */
@@ -9107,8 +9097,7 @@ int alloc_contig_range(unsigned long start, unsigned long end, 
	 * put back to page allocator so that buddy can use them.

	 */



	ret = start_isolate_page_range(pfn_max_align_down(start),

				pfn_max_align_up(end), migratetype, 0, gfp_mask);

	ret = start_isolate_page_range(start, end, migratetype, 0, gfp_mask);

	if (ret)

		goto done;
@@ -9189,8 +9178,7 @@ int alloc_contig_range(unsigned long start, unsigned long end, 
		free_contig_range(end, outer_end - end);



done:

	undo_isolate_page_range(pfn_max_align_down(start),

				pfn_max_align_up(end), migratetype);

	undo_isolate_page_range(start, end, migratetype);

	return ret;

}

EXPORT_SYMBOL(alloc_contig_range);

mm/page_isolation.c

+16 −17
Original line number Diff line number Diff line
@@ -444,7 +444,6 @@ static int isolate_single_pageblock(unsigned long boundary_pfn, gfp_t gfp_flags, 
 * be MIGRATE_ISOLATE.

 * @start_pfn:		The lower PFN of the range to be isolated.

 * @end_pfn:		The upper PFN of the range to be isolated.

 *			start_pfn/end_pfn must be aligned to pageblock_order.

 * @migratetype:	Migrate type to set in error recovery.

 * @flags:		The following flags are allowed (they can be combined in

 *			a bit mask)
@@ -491,33 +490,33 @@ int start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn, 
{

	unsigned long pfn;

	struct page *page;

	/* isolation is done at page block granularity */

	unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);

	unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);

	int ret;



	BUG_ON(!IS_ALIGNED(start_pfn, pageblock_nr_pages));

	BUG_ON(!IS_ALIGNED(end_pfn, pageblock_nr_pages));



	/* isolate [start_pfn, start_pfn + pageblock_nr_pages) pageblock */

	ret = isolate_single_pageblock(start_pfn, gfp_flags, false);

	/* isolate [isolate_start, isolate_start + pageblock_nr_pages) pageblock */

	ret = isolate_single_pageblock(isolate_start, gfp_flags, false);

	if (ret)

		return ret;



	/* isolate [end_pfn - pageblock_nr_pages, end_pfn) pageblock */

	ret = isolate_single_pageblock(end_pfn, gfp_flags, true);

	/* isolate [isolate_end - pageblock_nr_pages, isolate_end) pageblock */

	ret = isolate_single_pageblock(isolate_end, gfp_flags, true);

	if (ret) {

		unset_migratetype_isolate(pfn_to_page(start_pfn), migratetype);

		unset_migratetype_isolate(pfn_to_page(isolate_start), migratetype);

		return ret;

	}



	/* skip isolated pageblocks at the beginning and end */

	for (pfn = start_pfn + pageblock_nr_pages;

	     pfn < end_pfn - pageblock_nr_pages;

	for (pfn = isolate_start + pageblock_nr_pages;

	     pfn < isolate_end - pageblock_nr_pages;

	     pfn += pageblock_nr_pages) {

		page = __first_valid_page(pfn, pageblock_nr_pages);

		if (page && set_migratetype_isolate(page, migratetype, flags,

					start_pfn, end_pfn)) {

			undo_isolate_page_range(start_pfn, pfn, migratetype);

			undo_isolate_page_range(isolate_start, pfn, migratetype);

			unset_migratetype_isolate(

				pfn_to_page(end_pfn - pageblock_nr_pages),

				pfn_to_page(isolate_end - pageblock_nr_pages),

				migratetype);

			return -EBUSY;

		}
@@ -533,12 +532,12 @@ void undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn, 
{

	unsigned long pfn;

	struct page *page;

	unsigned long isolate_start = ALIGN_DOWN(start_pfn, pageblock_nr_pages);

	unsigned long isolate_end = ALIGN(end_pfn, pageblock_nr_pages);



	BUG_ON(!IS_ALIGNED(start_pfn, pageblock_nr_pages));

	BUG_ON(!IS_ALIGNED(end_pfn, pageblock_nr_pages));



	for (pfn = start_pfn;

	     pfn < end_pfn;

	for (pfn = isolate_start;

	     pfn < isolate_end;

	     pfn += pageblock_nr_pages) {

		page = __first_valid_page(pfn, pageblock_nr_pages);

		if (!page || !is_migrate_isolate_page(page))