summaryrefslogtreecommitdiffstats
path: root/include/linux/mmzone.h
diff options
context:
space:
mode:
Diffstat (limited to 'include/linux/mmzone.h')
-rw-r--r--include/linux/mmzone.h120
1 files changed, 75 insertions, 45 deletions
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index f45163c528e8..3693f1a52788 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -51,7 +51,8 @@ enum zone_stat_item {
NR_FILE_MAPPED, /* pagecache pages mapped into pagetables.
only modified from process context */
NR_FILE_PAGES,
- NR_SLAB, /* Pages used by slab allocator */
+ NR_SLAB_RECLAIMABLE,
+ NR_SLAB_UNRECLAIMABLE,
NR_PAGETABLE, /* used for pagetables */
NR_FILE_DIRTY,
NR_WRITEBACK,
@@ -88,53 +89,68 @@ struct per_cpu_pageset {
#define zone_pcp(__z, __cpu) (&(__z)->pageset[(__cpu)])
#endif
-#define ZONE_DMA 0
-#define ZONE_DMA32 1
-#define ZONE_NORMAL 2
-#define ZONE_HIGHMEM 3
-
-#define MAX_NR_ZONES 4 /* Sync this with ZONES_SHIFT */
-#define ZONES_SHIFT 2 /* ceil(log2(MAX_NR_ZONES)) */
-
+enum zone_type {
+ /*
+ * ZONE_DMA is used when there are devices that are not able
+ * to do DMA to all of addressable memory (ZONE_NORMAL). Then we
+ * carve out the portion of memory that is needed for these devices.
+ * The range is arch specific.
+ *
+ * Some examples
+ *
+ * Architecture Limit
+ * ---------------------------
+ * parisc, ia64, sparc <4G
+ * s390 <2G
+ * arm26 <48M
+ * arm Various
+ * alpha Unlimited or 0-16MB.
+ *
+ * i386, x86_64 and multiple other arches
+ * <16M.
+ */
+ ZONE_DMA,
+#ifdef CONFIG_ZONE_DMA32
+ /*
+ * x86_64 needs two ZONE_DMAs because it supports devices that are
+ * only able to do DMA to the lower 16M but also 32 bit devices that
+ * can only do DMA areas below 4G.
+ */
+ ZONE_DMA32,
+#endif
+ /*
+ * Normal addressable memory is in ZONE_NORMAL. DMA operations can be
+ * performed on pages in ZONE_NORMAL if the DMA devices support
+ * transfers to all addressable memory.
+ */
+ ZONE_NORMAL,
+#ifdef CONFIG_HIGHMEM
+ /*
+ * A memory area that is only addressable by the kernel through
+ * mapping portions into its own address space. This is for example
+ * used by i386 to allow the kernel to address the memory beyond
+ * 900MB. The kernel will set up special mappings (page
+ * table entries on i386) for each page that the kernel needs to
+ * access.
+ */
+ ZONE_HIGHMEM,
+#endif
+ MAX_NR_ZONES
+};
/*
* When a memory allocation must conform to specific limitations (such
* as being suitable for DMA) the caller will pass in hints to the
* allocator in the gfp_mask, in the zone modifier bits. These bits
* are used to select a priority ordered list of memory zones which
- * match the requested limits. GFP_ZONEMASK defines which bits within
- * the gfp_mask should be considered as zone modifiers. Each valid
- * combination of the zone modifier bits has a corresponding list
- * of zones (in node_zonelists). Thus for two zone modifiers there
- * will be a maximum of 4 (2 ** 2) zonelists, for 3 modifiers there will
- * be 8 (2 ** 3) zonelists. GFP_ZONETYPES defines the number of possible
- * combinations of zone modifiers in "zone modifier space".
- *
- * As an optimisation any zone modifier bits which are only valid when
- * no other zone modifier bits are set (loners) should be placed in
- * the highest order bits of this field. This allows us to reduce the
- * extent of the zonelists thus saving space. For example in the case
- * of three zone modifier bits, we could require up to eight zonelists.
- * If the left most zone modifier is a "loner" then the highest valid
- * zonelist would be four allowing us to allocate only five zonelists.
- * Use the first form for GFP_ZONETYPES when the left most bit is not
- * a "loner", otherwise use the second.
- *
- * NOTE! Make sure this matches the zones in <linux/gfp.h>
+ * match the requested limits. See gfp_zone() in include/linux/gfp.h
*/
-#define GFP_ZONEMASK 0x07
-/* #define GFP_ZONETYPES (GFP_ZONEMASK + 1) */ /* Non-loner */
-#define GFP_ZONETYPES ((GFP_ZONEMASK + 1) / 2 + 1) /* Loner */
-/*
- * On machines where it is needed (eg PCs) we divide physical memory
- * into multiple physical zones. On a 32bit PC we have 4 zones:
- *
- * ZONE_DMA < 16 MB ISA DMA capable memory
- * ZONE_DMA32 0 MB Empty
- * ZONE_NORMAL 16-896 MB direct mapped by the kernel
- * ZONE_HIGHMEM > 896 MB only page cache and user processes
- */
+#if !defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_HIGHMEM)
+#define ZONES_SHIFT 1
+#else
+#define ZONES_SHIFT 2
+#endif
struct zone {
/* Fields commonly accessed by the page allocator */
@@ -154,7 +170,8 @@ struct zone {
/*
* zone reclaim becomes active if more unmapped pages exist.
*/
- unsigned long min_unmapped_ratio;
+ unsigned long min_unmapped_pages;
+ unsigned long min_slab_pages;
struct per_cpu_pageset *pageset[NR_CPUS];
#else
struct per_cpu_pageset pageset[NR_CPUS];
@@ -266,7 +283,6 @@ struct zone {
char *name;
} ____cacheline_internodealigned_in_smp;
-
/*
* The "priority" of VM scanning is how much of the queues we will scan in one
* go. A value of 12 for DEF_PRIORITY implies that we will scan 1/4096th of the
@@ -304,7 +320,7 @@ struct zonelist {
struct bootmem_data;
typedef struct pglist_data {
struct zone node_zones[MAX_NR_ZONES];
- struct zonelist node_zonelists[GFP_ZONETYPES];
+ struct zonelist node_zonelists[MAX_NR_ZONES];
int nr_zones;
#ifdef CONFIG_FLAT_NODE_MEM_MAP
struct page *node_mem_map;
@@ -373,12 +389,16 @@ static inline int populated_zone(struct zone *zone)
return (!!zone->present_pages);
}
-static inline int is_highmem_idx(int idx)
+static inline int is_highmem_idx(enum zone_type idx)
{
+#ifdef CONFIG_HIGHMEM
return (idx == ZONE_HIGHMEM);
+#else
+ return 0;
+#endif
}
-static inline int is_normal_idx(int idx)
+static inline int is_normal_idx(enum zone_type idx)
{
return (idx == ZONE_NORMAL);
}
@@ -391,7 +411,11 @@ static inline int is_normal_idx(int idx)
*/
static inline int is_highmem(struct zone *zone)
{
+#ifdef CONFIG_HIGHMEM
return zone == zone->zone_pgdat->node_zones + ZONE_HIGHMEM;
+#else
+ return 0;
+#endif
}
static inline int is_normal(struct zone *zone)
@@ -401,7 +425,11 @@ static inline int is_normal(struct zone *zone)
static inline int is_dma32(struct zone *zone)
{
+#ifdef CONFIG_ZONE_DMA32
return zone == zone->zone_pgdat->node_zones + ZONE_DMA32;
+#else
+ return 0;
+#endif
}
static inline int is_dma(struct zone *zone)
@@ -421,6 +449,8 @@ int percpu_pagelist_fraction_sysctl_handler(struct ctl_table *, int, struct file
void __user *, size_t *, loff_t *);
int sysctl_min_unmapped_ratio_sysctl_handler(struct ctl_table *, int,
struct file *, void __user *, size_t *, loff_t *);
+int sysctl_min_slab_ratio_sysctl_handler(struct ctl_table *, int,
+ struct file *, void __user *, size_t *, loff_t *);
#include <linux/topology.h>
/* Returns the number of the current Node. */