[PATCH] optional ZONE_DMA: optional ZONE_DMA in the VM
Make ZONE_DMA optional in core code.
- ifdef all code for ZONE_DMA and related definitions following the example
for ZONE_DMA32 and ZONE_HIGHMEM.
- Without ZONE_DMA, ZONE_HIGHMEM and ZONE_DMA32 we get to a ZONES_SHIFT of
0.
- Modify the VM statistics to work correctly without a DMA zone.
- Modify slab to not create DMA slabs if there is no ZONE_DMA.
[akpm@osdl.org: cleanup]
[jdike@addtoit.com: build fix]
[apw@shadowen.org: Simplify calculation of the number of bits we need for ZONES_SHIFT]
Signed-off-by: Christoph Lameter <clameter@sgi.com>
Cc: Andi Kleen <ak@suse.de>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Matthew Wilcox <willy@debian.org>
Cc: James Bottomley <James.Bottomley@steeleye.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Andy Whitcroft <apw@shadowen.org>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/gfp.h b/include/linux/gfp.h
index 063799e..2a7d15b 100644
--- a/include/linux/gfp.h
+++ b/include/linux/gfp.h
@@ -85,8 +85,10 @@
static inline enum zone_type gfp_zone(gfp_t flags)
{
+#ifdef CONFIG_ZONE_DMA
if (flags & __GFP_DMA)
return ZONE_DMA;
+#endif
#ifdef CONFIG_ZONE_DMA32
if (flags & __GFP_DMA32)
return ZONE_DMA32;
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 398f2ec..ee9e314 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -96,6 +96,7 @@
#endif
enum zone_type {
+#ifdef CONFIG_ZONE_DMA
/*
* ZONE_DMA is used when there are devices that are not able
* to do DMA to all of addressable memory (ZONE_NORMAL). Then we
@@ -116,6 +117,7 @@
* <16M.
*/
ZONE_DMA,
+#endif
#ifdef CONFIG_ZONE_DMA32
/*
* x86_64 needs two ZONE_DMAs because it supports devices that are
@@ -152,11 +154,27 @@
* match the requested limits. See gfp_zone() in include/linux/gfp.h
*/
-#if !defined(CONFIG_ZONE_DMA32) && !defined(CONFIG_HIGHMEM)
+/*
+ * Count the active zones. Note that the use of defined(X) outside
+ * #if and family is not necessarily defined so ensure we cannot use
+ * it later. Use __ZONE_COUNT to work out how many shift bits we need.
+ */
+#define __ZONE_COUNT ( \
+ defined(CONFIG_ZONE_DMA) \
+ + defined(CONFIG_ZONE_DMA32) \
+ + 1 \
+ + defined(CONFIG_HIGHMEM) \
+)
+#if __ZONE_COUNT < 2
+#define ZONES_SHIFT 0
+#elif __ZONE_COUNT <= 2
#define ZONES_SHIFT 1
-#else
+#elif __ZONE_COUNT <= 4
#define ZONES_SHIFT 2
+#else
+#error ZONES_SHIFT -- too many zones configured adjust calculation
#endif
+#undef __ZONE_COUNT
struct zone {
/* Fields commonly accessed by the page allocator */
@@ -523,7 +541,11 @@
static inline int is_dma(struct zone *zone)
{
+#ifdef CONFIG_ZONE_DMA
return zone == zone->zone_pgdat->node_zones + ZONE_DMA;
+#else
+ return 0;
+#endif
}
/* These two functions are used to setup the per zone pages min values */
diff --git a/include/linux/slab_def.h b/include/linux/slab_def.h
index 4b463e6..5e43646 100644
--- a/include/linux/slab_def.h
+++ b/include/linux/slab_def.h
@@ -19,7 +19,9 @@
struct cache_sizes {
size_t cs_size;
struct kmem_cache *cs_cachep;
+#ifdef CONFIG_ZONE_DMA
struct kmem_cache *cs_dmacachep;
+#endif
};
extern struct cache_sizes malloc_sizes[];
@@ -39,9 +41,12 @@
__you_cannot_kmalloc_that_much();
}
found:
- return kmem_cache_alloc((flags & GFP_DMA) ?
- malloc_sizes[i].cs_dmacachep :
- malloc_sizes[i].cs_cachep, flags);
+#ifdef CONFIG_ZONE_DMA
+ if (flags & GFP_DMA)
+ return kmem_cache_alloc(malloc_sizes[i].cs_dmacachep,
+ flags);
+#endif
+ return kmem_cache_alloc(malloc_sizes[i].cs_cachep, flags);
}
return __kmalloc(size, flags);
}
@@ -62,9 +67,12 @@
__you_cannot_kzalloc_that_much();
}
found:
- return kmem_cache_zalloc((flags & GFP_DMA) ?
- malloc_sizes[i].cs_dmacachep :
- malloc_sizes[i].cs_cachep, flags);
+#ifdef CONFIG_ZONE_DMA
+ if (flags & GFP_DMA)
+ return kmem_cache_zalloc(malloc_sizes[i].cs_dmacachep,
+ flags);
+#endif
+ return kmem_cache_zalloc(malloc_sizes[i].cs_cachep, flags);
}
return __kzalloc(size, flags);
}
@@ -88,9 +96,13 @@
__you_cannot_kmalloc_that_much();
}
found:
- return kmem_cache_alloc_node((flags & GFP_DMA) ?
- malloc_sizes[i].cs_dmacachep :
- malloc_sizes[i].cs_cachep, flags, node);
+#ifdef CONFIG_ZONE_DMA
+ if (flags & GFP_DMA)
+ return kmem_cache_alloc_node(malloc_sizes[i].cs_dmacachep,
+ flags, node);
+#endif
+ return kmem_cache_alloc_node(malloc_sizes[i].cs_cachep,
+ flags, node);
}
return __kmalloc_node(size, flags, node);
}
diff --git a/include/linux/vmstat.h b/include/linux/vmstat.h
index 77caf91..7ba91f2 100644
--- a/include/linux/vmstat.h
+++ b/include/linux/vmstat.h
@@ -19,6 +19,12 @@
* generated will simply be the increment of a global address.
*/
+#ifdef CONFIG_ZONE_DMA
+#define DMA_ZONE(xx) xx##_DMA,
+#else
+#define DMA_ZONE(xx)
+#endif
+
#ifdef CONFIG_ZONE_DMA32
#define DMA32_ZONE(xx) xx##_DMA32,
#else
@@ -31,7 +37,7 @@
#define HIGHMEM_ZONE(xx)
#endif
-#define FOR_ALL_ZONES(xx) xx##_DMA, DMA32_ZONE(xx) xx##_NORMAL HIGHMEM_ZONE(xx)
+#define FOR_ALL_ZONES(xx) DMA_ZONE(xx) DMA32_ZONE(xx) xx##_NORMAL HIGHMEM_ZONE(xx)
enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
FOR_ALL_ZONES(PGALLOC),
@@ -96,7 +102,8 @@
#endif /* CONFIG_VM_EVENT_COUNTERS */
#define __count_zone_vm_events(item, zone, delta) \
- __count_vm_events(item##_DMA + zone_idx(zone), delta)
+ __count_vm_events(item##_NORMAL - ZONE_NORMAL + \
+ zone_idx(zone), delta)
/*
* Zone based page accounting with per cpu differentials.
@@ -143,14 +150,16 @@
struct zone *zones = NODE_DATA(node)->node_zones;
return
+#ifdef CONFIG_ZONE_DMA
+ zone_page_state(&zones[ZONE_DMA], item) +
+#endif
#ifdef CONFIG_ZONE_DMA32
zone_page_state(&zones[ZONE_DMA32], item) +
#endif
- zone_page_state(&zones[ZONE_NORMAL], item) +
#ifdef CONFIG_HIGHMEM
zone_page_state(&zones[ZONE_HIGHMEM], item) +
#endif
- zone_page_state(&zones[ZONE_DMA], item);
+ zone_page_state(&zones[ZONE_NORMAL], item);
}
extern void zone_statistics(struct zonelist *, struct zone *);
diff --git a/mm/Kconfig b/mm/Kconfig
index 50f7cfc..79360cf 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -161,3 +161,9 @@
default 64BIT
help
This option allows memory and IO resources to be 64 bit.
+
+config ZONE_DMA_FLAG
+ int
+ default "0" if !ZONE_DMA
+ default "1"
+
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 6cff138..d461b23 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -73,7 +73,9 @@
* don't need any ZONE_NORMAL reservation
*/
int sysctl_lowmem_reserve_ratio[MAX_NR_ZONES-1] = {
+#ifdef CONFIG_ZONE_DMA
256,
+#endif
#ifdef CONFIG_ZONE_DMA32
256,
#endif
@@ -85,7 +87,9 @@
EXPORT_SYMBOL(totalram_pages);
static char * const zone_names[MAX_NR_ZONES] = {
+#ifdef CONFIG_ZONE_DMA
"DMA",
+#endif
#ifdef CONFIG_ZONE_DMA32
"DMA32",
#endif
diff --git a/mm/slab.c b/mm/slab.c
index caa8f87..348396d 100644
--- a/mm/slab.c
+++ b/mm/slab.c
@@ -793,8 +793,10 @@
* has cs_{dma,}cachep==NULL. Thus no special case
* for large kmalloc calls required.
*/
+#ifdef CONFIG_ZONE_DMA
if (unlikely(gfpflags & GFP_DMA))
return csizep->cs_dmacachep;
+#endif
return csizep->cs_cachep;
}
@@ -1493,13 +1495,15 @@
ARCH_KMALLOC_FLAGS|SLAB_PANIC,
NULL, NULL);
}
-
- sizes->cs_dmacachep = kmem_cache_create(names->name_dma,
+#ifdef CONFIG_ZONE_DMA
+ sizes->cs_dmacachep = kmem_cache_create(
+ names->name_dma,
sizes->cs_size,
ARCH_KMALLOC_MINALIGN,
ARCH_KMALLOC_FLAGS|SLAB_CACHE_DMA|
SLAB_PANIC,
NULL, NULL);
+#endif
sizes++;
names++;
}
@@ -2321,7 +2325,7 @@
cachep->slab_size = slab_size;
cachep->flags = flags;
cachep->gfpflags = 0;
- if (flags & SLAB_CACHE_DMA)
+ if (CONFIG_ZONE_DMA_FLAG && (flags & SLAB_CACHE_DMA))
cachep->gfpflags |= GFP_DMA;
cachep->buffer_size = size;
cachep->reciprocal_buffer_size = reciprocal_value(size);
@@ -2643,10 +2647,12 @@
static void kmem_flagcheck(struct kmem_cache *cachep, gfp_t flags)
{
- if (flags & GFP_DMA)
- BUG_ON(!(cachep->gfpflags & GFP_DMA));
- else
- BUG_ON(cachep->gfpflags & GFP_DMA);
+ if (CONFIG_ZONE_DMA_FLAG) {
+ if (flags & GFP_DMA)
+ BUG_ON(!(cachep->gfpflags & GFP_DMA));
+ else
+ BUG_ON(cachep->gfpflags & GFP_DMA);
+ }
}
static void *slab_get_obj(struct kmem_cache *cachep, struct slab *slabp,
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 5ffa8c2..6c488d6 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -408,6 +408,12 @@
.show = frag_show,
};
+#ifdef CONFIG_ZONE_DMA
+#define TEXT_FOR_DMA(xx) xx "_dma",
+#else
+#define TEXT_FOR_DMA(xx)
+#endif
+
#ifdef CONFIG_ZONE_DMA32
#define TEXT_FOR_DMA32(xx) xx "_dma32",
#else
@@ -420,7 +426,7 @@
#define TEXT_FOR_HIGHMEM(xx)
#endif
-#define TEXTS_FOR_ZONES(xx) xx "_dma", TEXT_FOR_DMA32(xx) xx "_normal", \
+#define TEXTS_FOR_ZONES(xx) TEXT_FOR_DMA(xx) TEXT_FOR_DMA32(xx) xx "_normal", \
TEXT_FOR_HIGHMEM(xx)
static const char * const vmstat_text[] = {