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/drivers/base/Kconfig b/drivers/base/Kconfig
index 9b21469482aead0e69004e3285258fd3a0576796..08b4c520938463fd989bba879d791a3e418efd39 100644 (file)
--- a/drivers/base/Kconfig
+++ b/drivers/base/Kconfig
@@ -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

diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 3bdcab30ca4121e5067cb2eac291d039c6eee07e..105077aa7685c61dbb66cabc8473302283a0e3a5 100644 (file)
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -1,6 +1,11 @@
 #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

diff --git a/mm/Kconfig b/mm/Kconfig
index 82fed4eb2b6fe39cfd0476afe46e9589e02b386f..d5c8019c662793886224b872cc494e1ae3d00842 100644 (file)
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -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

diff --git a/mm/Makefile b/mm/Makefile
index 290bbfe33698651d6259b8dec10d98795d333ad4..92753e2d82dac41fe9a8c2f4633189ad723bbd07 100644 (file)
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -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

diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 667338e80e946ac196ae3137a282f34eee781262..228194728ccd1d7ba7c89f1c5665ff8b6d460389 100644 (file)
--- 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 @@ 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

diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index c9f04774f2b8117354bc6f38230bf94e645f701b..fb482cf438daa1709b8f380df22303d506186664 100644 (file)
--- 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)
 {