server-skynet-source-3rd-je.../include/jemalloc/internal/rtree.h

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/*
* This radix tree implementation is tailored to the singular purpose of
* tracking which chunks are currently owned by jemalloc. This functionality
* is mandatory for OS X, where jemalloc must be able to respond to object
* ownership queries.
*
*******************************************************************************
*/
#ifdef JEMALLOC_H_TYPES
typedef struct rtree_s rtree_t;
/*
* Size of each radix tree node (must be a power of 2). This impacts tree
* depth.
*/
#if (LG_SIZEOF_PTR == 2)
# define RTREE_NODESIZE (1U << 14)
#else
# define RTREE_NODESIZE CACHELINE
#endif
#endif /* JEMALLOC_H_TYPES */
/******************************************************************************/
#ifdef JEMALLOC_H_STRUCTS
struct rtree_s {
malloc_mutex_t mutex;
void **root;
unsigned height;
unsigned level2bits[1]; /* Dynamically sized. */
};
#endif /* JEMALLOC_H_STRUCTS */
/******************************************************************************/
#ifdef JEMALLOC_H_EXTERNS
rtree_t *rtree_new(unsigned bits);
#endif /* JEMALLOC_H_EXTERNS */
/******************************************************************************/
#ifdef JEMALLOC_H_INLINES
#ifndef JEMALLOC_ENABLE_INLINE
#ifndef JEMALLOC_DEBUG
void *rtree_get_locked(rtree_t *rtree, uintptr_t key);
#endif
void *rtree_get(rtree_t *rtree, uintptr_t key);
bool rtree_set(rtree_t *rtree, uintptr_t key, void *val);
#endif
#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_RTREE_C_))
#define RTREE_GET_GENERATE(f) \
/* The least significant bits of the key are ignored. */ \
JEMALLOC_INLINE void * \
f(rtree_t *rtree, uintptr_t key) \
{ \
void *ret; \
uintptr_t subkey; \
unsigned i, lshift, height, bits; \
void **node, **child; \
\
RTREE_LOCK(&rtree->mutex); \
for (i = lshift = 0, height = rtree->height, node = rtree->root;\
i < height - 1; \
i++, lshift += bits, node = child) { \
bits = rtree->level2bits[i]; \
subkey = (key << lshift) >> ((ZU(1) << (LG_SIZEOF_PTR + \
3)) - bits); \
child = (void**)node[subkey]; \
if (child == NULL) { \
RTREE_UNLOCK(&rtree->mutex); \
return (NULL); \
} \
} \
\
/* \
* node is a leaf, so it contains values rather than node \
* pointers. \
*/ \
bits = rtree->level2bits[i]; \
subkey = (key << lshift) >> ((ZU(1) << (LG_SIZEOF_PTR+3)) - \
bits); \
ret = node[subkey]; \
RTREE_UNLOCK(&rtree->mutex); \
\
RTREE_GET_VALIDATE \
return (ret); \
}
#ifdef JEMALLOC_DEBUG
# define RTREE_LOCK(l) malloc_mutex_lock(l)
# define RTREE_UNLOCK(l) malloc_mutex_unlock(l)
# define RTREE_GET_VALIDATE
RTREE_GET_GENERATE(rtree_get_locked)
# undef RTREE_LOCK
# undef RTREE_UNLOCK
# undef RTREE_GET_VALIDATE
#endif
#define RTREE_LOCK(l)
#define RTREE_UNLOCK(l)
#ifdef JEMALLOC_DEBUG
/*
* Suppose that it were possible for a jemalloc-allocated chunk to be
* munmap()ped, followed by a different allocator in another thread re-using
* overlapping virtual memory, all without invalidating the cached rtree
* value. The result would be a false positive (the rtree would claim that
* jemalloc owns memory that it had actually discarded). This scenario
* seems impossible, but the following assertion is a prudent sanity check.
*/
# define RTREE_GET_VALIDATE \
assert(rtree_get_locked(rtree, key) == ret);
#else
# define RTREE_GET_VALIDATE
#endif
RTREE_GET_GENERATE(rtree_get)
#undef RTREE_LOCK
#undef RTREE_UNLOCK
#undef RTREE_GET_VALIDATE
JEMALLOC_INLINE bool
rtree_set(rtree_t *rtree, uintptr_t key, void *val)
{
uintptr_t subkey;
unsigned i, lshift, height, bits;
void **node, **child;
malloc_mutex_lock(&rtree->mutex);
for (i = lshift = 0, height = rtree->height, node = rtree->root;
i < height - 1;
i++, lshift += bits, node = child) {
bits = rtree->level2bits[i];
subkey = (key << lshift) >> ((ZU(1) << (LG_SIZEOF_PTR+3)) -
bits);
child = (void**)node[subkey];
if (child == NULL) {
child = (void**)base_alloc(sizeof(void *) <<
rtree->level2bits[i+1]);
if (child == NULL) {
malloc_mutex_unlock(&rtree->mutex);
return (true);
}
memset(child, 0, sizeof(void *) <<
rtree->level2bits[i+1]);
node[subkey] = child;
}
}
/* node is a leaf, so it contains values rather than node pointers. */
bits = rtree->level2bits[i];
subkey = (key << lshift) >> ((ZU(1) << (LG_SIZEOF_PTR+3)) - bits);
node[subkey] = val;
malloc_mutex_unlock(&rtree->mutex);
return (false);
}
#endif
#endif /* JEMALLOC_H_INLINES */
/******************************************************************************/