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alistair23-linux/include/linux/slab_def.h

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#ifndef _LINUX_SLAB_DEF_H
#define _LINUX_SLAB_DEF_H
/*
* Definitions unique to the original Linux SLAB allocator.
*
* What we provide here is a way to optimize the frequent kmalloc
* calls in the kernel by selecting the appropriate general cache
* if kmalloc was called with a size that can be established at
* compile time.
*/
#include <linux/init.h>
#include <linux/compiler.h>
/*
* struct kmem_cache
*
* manages a cache.
*/
struct kmem_cache {
/* 1) Cache tunables. Protected by cache_chain_mutex */
unsigned int batchcount;
unsigned int limit;
unsigned int shared;
unsigned int size;
u32 reciprocal_buffer_size;
/* 2) touched by every alloc & free from the backend */
unsigned int flags; /* constant flags */
unsigned int num; /* # of objs per slab */
/* 3) cache_grow/shrink */
/* order of pgs per slab (2^n) */
unsigned int gfporder;
/* force GFP flags, e.g. GFP_DMA */
gfp_t allocflags;
size_t colour; /* cache colouring range */
unsigned int colour_off; /* colour offset */
struct kmem_cache *slabp_cache;
unsigned int slab_size;
/* constructor func */
void (*ctor)(void *obj);
/* 4) cache creation/removal */
const char *name;
struct list_head list;
int refcount;
int object_size;
int align;
/* 5) statistics */
#ifdef CONFIG_DEBUG_SLAB
unsigned long num_active;
unsigned long num_allocations;
unsigned long high_mark;
unsigned long grown;
unsigned long reaped;
unsigned long errors;
unsigned long max_freeable;
unsigned long node_allocs;
unsigned long node_frees;
unsigned long node_overflow;
atomic_t allochit;
atomic_t allocmiss;
atomic_t freehit;
atomic_t freemiss;
/*
* If debugging is enabled, then the allocator can add additional
* fields and/or padding to every object. size contains the total
* object size including these internal fields, the following two
* variables contain the offset to the user object and its size.
*/
int obj_offset;
#endif /* CONFIG_DEBUG_SLAB */
#ifdef CONFIG_MEMCG_KMEM
struct memcg_cache_params *memcg_params;
#endif
/* 6) per-cpu/per-node data, touched during every alloc/free */
/*
* We put array[] at the end of kmem_cache, because we want to size
* this array to nr_cpu_ids slots instead of NR_CPUS
* (see kmem_cache_init())
* We still use [NR_CPUS] and not [1] or [0] because cache_cache
* is statically defined, so we reserve the max number of cpus.
*
* We also need to guarantee that the list is able to accomodate a
* pointer for each node since "nodelists" uses the remainder of
* available pointers.
*/
struct kmem_cache_node **node;
struct array_cache *array[NR_CPUS + MAX_NUMNODES];
/*
* Do not add fields after array[]
*/
};
slob: initial NUMA support This adds preliminary NUMA support to SLOB, primarily aimed at systems with small nodes (tested all the way down to a 128kB SRAM block), whether asymmetric or otherwise. We follow the same conventions as SLAB/SLUB, preferring current node placement for new pages, or with explicit placement, if a node has been specified. Presently on UP NUMA this has the side-effect of preferring node#0 allocations (since numa_node_id() == 0, though this could be reworked if we could hand off a pfn to determine node placement), so single-CPU NUMA systems will want to place smaller nodes further out in terms of node id. Once a page has been bound to a node (via explicit node id typing), we only do block allocations from partial free pages that have a matching node id in the page flags. The current implementation does have some scalability problems, in that all partial free pages are tracked in the global freelist (with contention due to the single spinlock). However, these are things that are being reworked for SMP scalability first, while things like per-node freelists can easily be built on top of this sort of functionality once it's been added. More background can be found in: http://marc.info/?l=linux-mm&m=118117916022379&w=2 http://marc.info/?l=linux-mm&m=118170446306199&w=2 http://marc.info/?l=linux-mm&m=118187859420048&w=2 and subsequent threads. Acked-by: Christoph Lameter <clameter@sgi.com> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 00:38:22 -06:00
void *kmem_cache_alloc(struct kmem_cache *, gfp_t);
void *__kmalloc(size_t size, gfp_t flags);
#ifdef CONFIG_TRACING
extern void *kmem_cache_alloc_trace(struct kmem_cache *, gfp_t, size_t);
#else
static __always_inline void *
kmem_cache_alloc_trace(struct kmem_cache *cachep, gfp_t flags, size_t size)
{
return kmem_cache_alloc(cachep, flags);
}
#endif
static __always_inline void *kmalloc(size_t size, gfp_t flags)
{
struct kmem_cache *cachep;
void *ret;
if (__builtin_constant_p(size)) {
int i;
if (!size)
return ZERO_SIZE_PTR;
if (WARN_ON_ONCE(size > KMALLOC_MAX_SIZE))
return NULL;
i = kmalloc_index(size);
#ifdef CONFIG_ZONE_DMA
if (flags & GFP_DMA)
cachep = kmalloc_dma_caches[i];
else
#endif
cachep = kmalloc_caches[i];
ret = kmem_cache_alloc_trace(cachep, flags, size);
return ret;
}
return __kmalloc(size, flags);
}
#ifdef CONFIG_NUMA
extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
slob: initial NUMA support This adds preliminary NUMA support to SLOB, primarily aimed at systems with small nodes (tested all the way down to a 128kB SRAM block), whether asymmetric or otherwise. We follow the same conventions as SLAB/SLUB, preferring current node placement for new pages, or with explicit placement, if a node has been specified. Presently on UP NUMA this has the side-effect of preferring node#0 allocations (since numa_node_id() == 0, though this could be reworked if we could hand off a pfn to determine node placement), so single-CPU NUMA systems will want to place smaller nodes further out in terms of node id. Once a page has been bound to a node (via explicit node id typing), we only do block allocations from partial free pages that have a matching node id in the page flags. The current implementation does have some scalability problems, in that all partial free pages are tracked in the global freelist (with contention due to the single spinlock). However, these are things that are being reworked for SMP scalability first, while things like per-node freelists can easily be built on top of this sort of functionality once it's been added. More background can be found in: http://marc.info/?l=linux-mm&m=118117916022379&w=2 http://marc.info/?l=linux-mm&m=118170446306199&w=2 http://marc.info/?l=linux-mm&m=118187859420048&w=2 and subsequent threads. Acked-by: Christoph Lameter <clameter@sgi.com> Acked-by: Matt Mackall <mpm@selenic.com> Signed-off-by: Paul Mundt <lethal@linux-sh.org> Acked-by: Nick Piggin <nickpiggin@yahoo.com.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-16 00:38:22 -06:00
extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
#ifdef CONFIG_TRACING
extern void *kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
gfp_t flags,
int nodeid,
size_t size);
#else
static __always_inline void *
kmem_cache_alloc_node_trace(struct kmem_cache *cachep,
gfp_t flags,
int nodeid,
size_t size)
{
return kmem_cache_alloc_node(cachep, flags, nodeid);
}
#endif
static __always_inline void *kmalloc_node(size_t size, gfp_t flags, int node)
{
struct kmem_cache *cachep;
if (__builtin_constant_p(size)) {
int i;
if (!size)
return ZERO_SIZE_PTR;
if (WARN_ON_ONCE(size > KMALLOC_MAX_SIZE))
return NULL;
i = kmalloc_index(size);
#ifdef CONFIG_ZONE_DMA
if (flags & GFP_DMA)
cachep = kmalloc_dma_caches[i];
else
#endif
cachep = kmalloc_caches[i];
return kmem_cache_alloc_node_trace(cachep, flags, node, size);
}
return __kmalloc_node(size, flags, node);
}
#endif /* CONFIG_NUMA */
#endif /* _LINUX_SLAB_DEF_H */