Commit ee6f509c authored by Minchan Kim's avatar Minchan Kim Committed by Linus Torvalds
Browse files

mm: factor out memory isolate functions 



mm/page_alloc.c has some memory isolation functions but they are used only
when we enable CONFIG_{CMA|MEMORY_HOTPLUG|MEMORY_FAILURE}.  So let's make
it configurable by new CONFIG_MEMORY_ISOLATION so that it can reduce
binary size and we can check it simple by CONFIG_MEMORY_ISOLATION, not if
defined CONFIG_{CMA|MEMORY_HOTPLUG|MEMORY_FAILURE}.

Signed-off-by: default avatarMinchan Kim <minchan@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: default avatarKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 876aafbf

drivers/base/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -196,6 +196,7 @@ config CMA 
	bool "Contiguous Memory Allocator (EXPERIMENTAL)"

	depends on HAVE_DMA_CONTIGUOUS && HAVE_MEMBLOCK && EXPERIMENTAL

	select MIGRATION

	select MEMORY_ISOLATION

	help

	  This enables the Contiguous Memory Allocator which allows drivers

	  to allocate big physically-contiguous blocks of memory for use with

include/linux/page-isolation.h

+9 −4
Original line number Diff line number Diff line 
#ifndef __LINUX_PAGEISOLATION_H

#define __LINUX_PAGEISOLATION_H





bool has_unmovable_pages(struct zone *zone, struct page *page, int count);

void set_pageblock_migratetype(struct page *page, int migratetype);

int move_freepages_block(struct zone *zone, struct page *page,

				int migratetype);

/*

 * Changes migrate type in [start_pfn, end_pfn) to be MIGRATE_ISOLATE.

 * If specified range includes migrate types other than MOVABLE or CMA,
@@ -10,7 +15,7 @@ 
 * free all pages in the range. test_page_isolated() can be used for

 * test it.

 */

extern int

int

start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,

			 unsigned migratetype);
@@ -18,7 +23,7 @@ start_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn, 
 * Changes MIGRATE_ISOLATE to MIGRATE_MOVABLE.

 * target range is [start_pfn, end_pfn)

 */

extern int

int

undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,

			unsigned migratetype);
@@ -30,8 +35,8 @@ int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn); 
/*

 * Internal functions. Changes pageblock's migrate type.

 */

extern int set_migratetype_isolate(struct page *page);

extern void unset_migratetype_isolate(struct page *page, unsigned migratetype);

int set_migratetype_isolate(struct page *page);

void unset_migratetype_isolate(struct page *page, unsigned migratetype);





#endif

mm/Kconfig

+5 −0
Original line number Diff line number Diff line
@@ -140,9 +140,13 @@ config ARCH_DISCARD_MEMBLOCK 
config NO_BOOTMEM

	boolean



config MEMORY_ISOLATION

	boolean



# eventually, we can have this option just 'select SPARSEMEM'

config MEMORY_HOTPLUG

	bool "Allow for memory hot-add"

	select MEMORY_ISOLATION

	depends on SPARSEMEM || X86_64_ACPI_NUMA

	depends on HOTPLUG && ARCH_ENABLE_MEMORY_HOTPLUG

	depends on (IA64 || X86 || PPC_BOOK3S_64 || SUPERH || S390)
@@ -272,6 +276,7 @@ config MEMORY_FAILURE 
	depends on MMU

	depends on ARCH_SUPPORTS_MEMORY_FAILURE

	bool "Enable recovery from hardware memory errors"

	select MEMORY_ISOLATION

	help

	  Enables code to recover from some memory failures on systems

	  with MCA recovery. This allows a system to continue running

mm/Makefile

+3 −2
Original line number Diff line number Diff line
@@ -15,8 +15,8 @@ obj-y := filemap.o mempool.o oom_kill.o fadvise.o \ 
			   maccess.o page_alloc.o page-writeback.o \

			   readahead.o swap.o truncate.o vmscan.o shmem.o \

			   prio_tree.o util.o mmzone.o vmstat.o backing-dev.o \

			   page_isolation.o mm_init.o mmu_context.o percpu.o \

			   compaction.o slab_common.o $(mmu-y)

			   mm_init.o mmu_context.o percpu.o slab_common.o \

			   compaction.o $(mmu-y)



obj-y += init-mm.o
@@ -56,3 +56,4 @@ obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o 
obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o

obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o

obj-$(CONFIG_CLEANCACHE) += cleancache.o

obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o

mm/page_alloc.c

+4 −76
Original line number Diff line number Diff line
@@ -51,7 +51,6 @@ 
#include <linux/page_cgroup.h>

#include <linux/debugobjects.h>

#include <linux/kmemleak.h>

#include <linux/memory.h>

#include <linux/compaction.h>

#include <trace/events/kmem.h>

#include <linux/ftrace_event.h>
@@ -219,7 +218,7 @@ EXPORT_SYMBOL(nr_online_nodes); 


int page_group_by_mobility_disabled __read_mostly;



static void set_pageblock_migratetype(struct page *page, int migratetype)

void set_pageblock_migratetype(struct page *page, int migratetype)

{



	if (unlikely(page_group_by_mobility_disabled))
@@ -954,7 +953,7 @@ static int move_freepages(struct zone *zone, 
	return pages_moved;

}



static int move_freepages_block(struct zone *zone, struct page *page,

int move_freepages_block(struct zone *zone, struct page *page,

				int migratetype)

{

	unsigned long start_pfn, end_pfn;
@@ -5463,8 +5462,7 @@ void set_pageblock_flags_group(struct page *page, unsigned long flags, 
 * MIGRATE_MOVABLE block might include unmovable pages. It means you can't

 * expect this function should be exact.

 */

static bool

__has_unmovable_pages(struct zone *zone, struct page *page, int count)

bool has_unmovable_pages(struct zone *zone, struct page *page, int count)

{

	unsigned long pfn, iter, found;

	int mt;
@@ -5541,77 +5539,7 @@ bool is_pageblock_removable_nolock(struct page *page) 
			zone->zone_start_pfn + zone->spanned_pages <= pfn)

		return false;



	return !__has_unmovable_pages(zone, page, 0);

}



int set_migratetype_isolate(struct page *page)

{

	struct zone *zone;

	unsigned long flags, pfn;

	struct memory_isolate_notify arg;

	int notifier_ret;

	int ret = -EBUSY;



	zone = page_zone(page);



	spin_lock_irqsave(&zone->lock, flags);



	pfn = page_to_pfn(page);

	arg.start_pfn = pfn;

	arg.nr_pages = pageblock_nr_pages;

	arg.pages_found = 0;



	/*

	 * It may be possible to isolate a pageblock even if the

	 * migratetype is not MIGRATE_MOVABLE. The memory isolation

	 * notifier chain is used by balloon drivers to return the

	 * number of pages in a range that are held by the balloon

	 * driver to shrink memory. If all the pages are accounted for

	 * by balloons, are free, or on the LRU, isolation can continue.

	 * Later, for example, when memory hotplug notifier runs, these

	 * pages reported as "can be isolated" should be isolated(freed)

	 * by the balloon driver through the memory notifier chain.

	 */

	notifier_ret = memory_isolate_notify(MEM_ISOLATE_COUNT, &arg);

	notifier_ret = notifier_to_errno(notifier_ret);

	if (notifier_ret)

		goto out;

	/*

	 * FIXME: Now, memory hotplug doesn't call shrink_slab() by itself.

	 * We just check MOVABLE pages.

	 */

	if (!__has_unmovable_pages(zone, page, arg.pages_found))

		ret = 0;

	/*

	 * Unmovable means "not-on-lru" pages. If Unmovable pages are

	 * larger than removable-by-driver pages reported by notifier,

	 * we'll fail.

	 */



out:

	if (!ret) {

		set_pageblock_migratetype(page, MIGRATE_ISOLATE);

		move_freepages_block(zone, page, MIGRATE_ISOLATE);

	}



	spin_unlock_irqrestore(&zone->lock, flags);

	if (!ret)

		drain_all_pages();

	return ret;

}



void unset_migratetype_isolate(struct page *page, unsigned migratetype)

{

	struct zone *zone;

	unsigned long flags;

	zone = page_zone(page);

	spin_lock_irqsave(&zone->lock, flags);

	if (get_pageblock_migratetype(page) != MIGRATE_ISOLATE)

		goto out;

	set_pageblock_migratetype(page, migratetype);

	move_freepages_block(zone, page, migratetype);

out:

	spin_unlock_irqrestore(&zone->lock, flags);

	return !has_unmovable_pages(zone, page, 0);

}



#ifdef CONFIG_CMA

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