From e12ba74d8ff3e2f73a583500d7095e406df4d093 Mon Sep 17 00:00:00 2001 From: Mel Gorman Date: Tue, 16 Oct 2007 01:25:52 -0700 Subject: Group short-lived and reclaimable kernel allocations This patch marks a number of allocations that are either short-lived such as network buffers or are reclaimable such as inode allocations. When something like updatedb is called, long-lived and unmovable kernel allocations tend to be spread throughout the address space which increases fragmentation. This patch groups these allocations together as much as possible by adding a new MIGRATE_TYPE. The MIGRATE_RECLAIMABLE type is for allocations that can be reclaimed on demand, but not moved. i.e. they can be migrated by deleting them and re-reading the information from elsewhere. Signed-off-by: Mel Gorman Cc: Andy Whitcroft Cc: Christoph Lameter Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/gfp.h | 15 ++++++++++++--- include/linux/mmzone.h | 6 ++++-- include/linux/pageblock-flags.h | 2 +- include/linux/slab.h | 4 +++- 4 files changed, 20 insertions(+), 7 deletions(-) (limited to 'include') diff --git a/include/linux/gfp.h b/include/linux/gfp.h index da8aa872eb6..f8ffcd401c5 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -48,9 +48,10 @@ struct vm_area_struct; #define __GFP_NOMEMALLOC ((__force gfp_t)0x10000u) /* Don't use emergency reserves */ #define __GFP_HARDWALL ((__force gfp_t)0x20000u) /* Enforce hardwall cpuset memory allocs */ #define __GFP_THISNODE ((__force gfp_t)0x40000u)/* No fallback, no policies */ -#define __GFP_MOVABLE ((__force gfp_t)0x80000u) /* Page is movable */ +#define __GFP_RECLAIMABLE ((__force gfp_t)0x80000u) /* Page is reclaimable */ +#define __GFP_MOVABLE ((__force gfp_t)0x100000u) /* Page is movable */ -#define __GFP_BITS_SHIFT 20 /* Room for 20 __GFP_FOO bits */ +#define __GFP_BITS_SHIFT 21 /* Room for 21 __GFP_FOO bits */ #define __GFP_BITS_MASK ((__force gfp_t)((1 << __GFP_BITS_SHIFT) - 1)) /* This equals 0, but use constants in case they ever change */ @@ -60,6 +61,8 @@ struct vm_area_struct; #define GFP_NOIO (__GFP_WAIT) #define GFP_NOFS (__GFP_WAIT | __GFP_IO) #define GFP_KERNEL (__GFP_WAIT | __GFP_IO | __GFP_FS) +#define GFP_TEMPORARY (__GFP_WAIT | __GFP_IO | __GFP_FS | \ + __GFP_RECLAIMABLE) #define GFP_USER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL) #define GFP_HIGHUSER (__GFP_WAIT | __GFP_IO | __GFP_FS | __GFP_HARDWALL | \ __GFP_HIGHMEM) @@ -80,7 +83,7 @@ struct vm_area_struct; #endif /* This mask makes up all the page movable related flags */ -#define GFP_MOVABLE_MASK (__GFP_MOVABLE) +#define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) /* Control page allocator reclaim behavior */ #define GFP_RECLAIM_MASK (__GFP_WAIT|__GFP_HIGH|__GFP_IO|__GFP_FS|\ @@ -129,6 +132,12 @@ static inline enum zone_type gfp_zone(gfp_t flags) return base + ZONE_NORMAL; } +static inline gfp_t set_migrateflags(gfp_t gfp, gfp_t migrate_flags) +{ + BUG_ON((gfp & GFP_MOVABLE_MASK) == GFP_MOVABLE_MASK); + return (gfp & ~(GFP_MOVABLE_MASK)) | migrate_flags; +} + /* * There is only one page-allocator function, and two main namespaces to * it. The alloc_page*() variants return 'struct page *' and as such diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 7d7e4fe0fda..4721e9aa3ce 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -35,10 +35,12 @@ #ifdef CONFIG_PAGE_GROUP_BY_MOBILITY #define MIGRATE_UNMOVABLE 0 -#define MIGRATE_MOVABLE 1 -#define MIGRATE_TYPES 2 +#define MIGRATE_RECLAIMABLE 1 +#define MIGRATE_MOVABLE 2 +#define MIGRATE_TYPES 3 #else #define MIGRATE_UNMOVABLE 0 +#define MIGRATE_UNRECLAIMABLE 0 #define MIGRATE_MOVABLE 0 #define MIGRATE_TYPES 1 #endif diff --git a/include/linux/pageblock-flags.h b/include/linux/pageblock-flags.h index 3619d52a425..5456da6b4ad 100644 --- a/include/linux/pageblock-flags.h +++ b/include/linux/pageblock-flags.h @@ -31,7 +31,7 @@ /* Bit indices that affect a whole block of pages */ enum pageblock_bits { - PB_range(PB_migrate, 1), /* 1 bit required for migrate types */ + PB_range(PB_migrate, 2), /* 2 bits required for migrate types */ NR_PAGEBLOCK_BITS }; diff --git a/include/linux/slab.h b/include/linux/slab.h index d859354b9e5..3a5bad3ad12 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -24,12 +24,14 @@ #define SLAB_HWCACHE_ALIGN 0x00002000UL /* Align objs on cache lines */ #define SLAB_CACHE_DMA 0x00004000UL /* Use GFP_DMA memory */ #define SLAB_STORE_USER 0x00010000UL /* DEBUG: Store the last owner for bug hunting */ -#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ #define SLAB_PANIC 0x00040000UL /* Panic if kmem_cache_create() fails */ #define SLAB_DESTROY_BY_RCU 0x00080000UL /* Defer freeing slabs to RCU */ #define SLAB_MEM_SPREAD 0x00100000UL /* Spread some memory over cpuset */ #define SLAB_TRACE 0x00200000UL /* Trace allocations and frees */ +/* The following flags affect the page allocator grouping pages by mobility */ +#define SLAB_RECLAIM_ACCOUNT 0x00020000UL /* Objects are reclaimable */ +#define SLAB_TEMPORARY SLAB_RECLAIM_ACCOUNT /* Objects are short-lived */ /* * ZERO_SIZE_PTR will be returned for zero sized kmalloc requests. * -- cgit v1.2.3