Now mm/page_alloc.c has some memory isolation functions but they are used oly 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}. * from v2 - rebase on mmotm-2012-07-10-16-59 * from v1 - rebase on next-20120626 Cc: Andi Kleen <andi@xxxxxxxxxxxxxx> Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> Signed-off-by: Minchan Kim <minchan@xxxxxxxxxx> --- drivers/base/Kconfig | 1 + include/linux/page-isolation.h | 13 +++++-- mm/Kconfig | 5 +++ mm/Makefile | 4 +- mm/page_alloc.c | 80 ++-------------------------------------- mm/page_isolation.c | 71 +++++++++++++++++++++++++++++++++++ 6 files changed, 92 insertions(+), 82 deletions(-) diff --git a/drivers/base/Kconfig b/drivers/base/Kconfig index 9b21469..08b4c52 100644 --- 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 3bdcab3..105077a 100644 --- 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 82fed4e..d5c8019 100644 --- 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 262360a..7deaa29 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -15,8 +15,7 @@ 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 $(mmu-y) + mm_init.o mmu_context.o percpu.o compaction.o $(mmu-y) obj-y += init-mm.o ifdef CONFIG_NO_BOOTMEM @@ -55,3 +54,4 @@ obj-$(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 dd94467..f17e6e4 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 @@ 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)) @@ -953,7 +952,7 @@ 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; @@ -5468,8 +5467,7 @@ 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; @@ -5546,77 +5544,7 @@ 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 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) { -- 1.7.9.5 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>