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: Minchan Kim <minchan@kernel.org>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: KAMEZAWA 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: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/mm/Kconfig b/mm/Kconfig
index 82fed4e..d5c8019 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -140,9 +140,13 @@
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 @@
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
diff --git a/mm/Makefile b/mm/Makefile
index 290bbfe..92753e2 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -15,8 +15,8 @@
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_DEBUG_KMEMLEAK) += kmemleak.o
obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o
obj-$(CONFIG_CLEANCACHE) += cleancache.o
+obj-$(CONFIG_MEMORY_ISOLATION) += page_isolation.o
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 667338e..2281947 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -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 @@
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 @@
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 @@
* 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 @@
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
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index c9f0477..fb482cf 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -5,8 +5,79 @@
#include <linux/mm.h>
#include <linux/page-isolation.h>
#include <linux/pageblock-flags.h>
+#include <linux/memory.h>
#include "internal.h"
+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;
+
+ /*
+ * immobile means "not-on-lru" paes. If immobile is 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);
+}
+
static inline struct page *
__first_valid_page(unsigned long pfn, unsigned long nr_pages)
{