linux/include/linux/slab_def.h

218 lines
5.0 KiB
C

#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 <asm/page.h> /* kmalloc_sizes.h needs PAGE_SIZE */
#include <asm/cache.h> /* kmalloc_sizes.h needs L1_CACHE_BYTES */
#include <linux/compiler.h>
#include <trace/events/kmem.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 buffer_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 gfpflags;
size_t colour; /* cache colouring range */
unsigned int colour_off; /* colour offset */
struct kmem_cache *slabp_cache;
unsigned int slab_size;
unsigned int dflags; /* dynamic flags */
/* constructor func */
void (*ctor)(void *obj);
/* 4) cache creation/removal */
const char *name;
struct list_head next;
/* 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. buffer_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;
int obj_size;
#endif /* CONFIG_DEBUG_SLAB */
/* 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.
*/
struct kmem_list3 **nodelists;
struct array_cache *array[NR_CPUS];
/*
* Do not add fields after array[]
*/
};
/* Size description struct for general caches. */
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[];
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(size_t size,
struct kmem_cache *cachep, gfp_t flags);
extern size_t slab_buffer_size(struct kmem_cache *cachep);
#else
static __always_inline void *
kmem_cache_alloc_trace(size_t size, struct kmem_cache *cachep, gfp_t flags)
{
return kmem_cache_alloc(cachep, flags);
}
static inline size_t slab_buffer_size(struct kmem_cache *cachep)
{
return 0;
}
#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 = 0;
if (!size)
return ZERO_SIZE_PTR;
#define CACHE(x) \
if (size <= x) \
goto found; \
else \
i++;
#include <linux/kmalloc_sizes.h>
#undef CACHE
return NULL;
found:
#ifdef CONFIG_ZONE_DMA
if (flags & GFP_DMA)
cachep = malloc_sizes[i].cs_dmacachep;
else
#endif
cachep = malloc_sizes[i].cs_cachep;
ret = kmem_cache_alloc_trace(size, cachep, flags);
return ret;
}
return __kmalloc(size, flags);
}
#ifdef CONFIG_NUMA
extern void *__kmalloc_node(size_t size, gfp_t flags, int node);
extern void *kmem_cache_alloc_node(struct kmem_cache *, gfp_t flags, int node);
#ifdef CONFIG_TRACING
extern void *kmem_cache_alloc_node_trace(size_t size,
struct kmem_cache *cachep,
gfp_t flags,
int nodeid);
#else
static __always_inline void *
kmem_cache_alloc_node_trace(size_t size,
struct kmem_cache *cachep,
gfp_t flags,
int nodeid)
{
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 = 0;
if (!size)
return ZERO_SIZE_PTR;
#define CACHE(x) \
if (size <= x) \
goto found; \
else \
i++;
#include <linux/kmalloc_sizes.h>
#undef CACHE
return NULL;
found:
#ifdef CONFIG_ZONE_DMA
if (flags & GFP_DMA)
cachep = malloc_sizes[i].cs_dmacachep;
else
#endif
cachep = malloc_sizes[i].cs_cachep;
return kmem_cache_alloc_node_trace(size, cachep, flags, node);
}
return __kmalloc_node(size, flags, node);
}
#endif /* CONFIG_NUMA */
#endif /* _LINUX_SLAB_DEF_H */