6c460ad91b
Specialize fast path to avoid code that cannot execute for dependent loads. Manually unroll.
130 lines
3.2 KiB
C
130 lines
3.2 KiB
C
#define JEMALLOC_RTREE_C_
|
|
#include "jemalloc/internal/jemalloc_internal.h"
|
|
|
|
static unsigned
|
|
hmin(unsigned ha, unsigned hb)
|
|
{
|
|
|
|
return (ha < hb ? ha : hb);
|
|
}
|
|
|
|
/* Only the most significant bits of keys passed to rtree_[gs]et() are used. */
|
|
bool
|
|
rtree_new(rtree_t *rtree, unsigned bits, rtree_node_alloc_t *alloc,
|
|
rtree_node_dalloc_t *dalloc)
|
|
{
|
|
unsigned bits_in_leaf, height, i;
|
|
|
|
assert(RTREE_HEIGHT_MAX == ((ZU(1) << (LG_SIZEOF_PTR+3)) /
|
|
RTREE_BITS_PER_LEVEL));
|
|
assert(bits > 0 && bits <= (sizeof(uintptr_t) << 3));
|
|
|
|
bits_in_leaf = (bits % RTREE_BITS_PER_LEVEL) == 0 ? RTREE_BITS_PER_LEVEL
|
|
: (bits % RTREE_BITS_PER_LEVEL);
|
|
if (bits > bits_in_leaf) {
|
|
height = 1 + (bits - bits_in_leaf) / RTREE_BITS_PER_LEVEL;
|
|
if ((height-1) * RTREE_BITS_PER_LEVEL + bits_in_leaf != bits)
|
|
height++;
|
|
} else
|
|
height = 1;
|
|
assert((height-1) * RTREE_BITS_PER_LEVEL + bits_in_leaf == bits);
|
|
|
|
rtree->alloc = alloc;
|
|
rtree->dalloc = dalloc;
|
|
rtree->height = height;
|
|
|
|
/* Root level. */
|
|
rtree->levels[0].subtree = NULL;
|
|
rtree->levels[0].bits = (height > 1) ? RTREE_BITS_PER_LEVEL :
|
|
bits_in_leaf;
|
|
rtree->levels[0].cumbits = rtree->levels[0].bits;
|
|
/* Interior levels. */
|
|
for (i = 1; i < height-1; i++) {
|
|
rtree->levels[i].subtree = NULL;
|
|
rtree->levels[i].bits = RTREE_BITS_PER_LEVEL;
|
|
rtree->levels[i].cumbits = rtree->levels[i-1].cumbits +
|
|
RTREE_BITS_PER_LEVEL;
|
|
}
|
|
/* Leaf level. */
|
|
if (height > 1) {
|
|
rtree->levels[height-1].subtree = NULL;
|
|
rtree->levels[height-1].bits = bits_in_leaf;
|
|
rtree->levels[height-1].cumbits = bits;
|
|
}
|
|
|
|
/* Compute lookup table to be used by rtree_start_level(). */
|
|
for (i = 0; i < RTREE_HEIGHT_MAX; i++) {
|
|
rtree->start_level[i] = hmin(RTREE_HEIGHT_MAX - 1 - i, height -
|
|
1);
|
|
}
|
|
|
|
return (false);
|
|
}
|
|
|
|
static void
|
|
rtree_delete_subtree(rtree_t *rtree, rtree_node_elm_t *node, unsigned level)
|
|
{
|
|
|
|
if (level + 1 < rtree->height) {
|
|
size_t nchildren, i;
|
|
|
|
nchildren = ZU(1) << rtree->levels[level].bits;
|
|
for (i = 0; i < nchildren; i++) {
|
|
rtree_node_elm_t *child = node[i].child;
|
|
if (child != NULL)
|
|
rtree_delete_subtree(rtree, child, level + 1);
|
|
}
|
|
}
|
|
rtree->dalloc(node);
|
|
}
|
|
|
|
void
|
|
rtree_delete(rtree_t *rtree)
|
|
{
|
|
unsigned i;
|
|
|
|
for (i = 0; i < rtree->height; i++) {
|
|
rtree_node_elm_t *subtree = rtree->levels[i].subtree;
|
|
if (subtree != NULL)
|
|
rtree_delete_subtree(rtree, subtree, i);
|
|
}
|
|
}
|
|
|
|
static rtree_node_elm_t *
|
|
rtree_node_init(rtree_t *rtree, unsigned level, rtree_node_elm_t **elmp)
|
|
{
|
|
rtree_node_elm_t *node;
|
|
|
|
if (atomic_cas_p((void **)elmp, NULL, RTREE_NODE_INITIALIZING)) {
|
|
/*
|
|
* Another thread is already in the process of initializing.
|
|
* Spin-wait until initialization is complete.
|
|
*/
|
|
do {
|
|
CPU_SPINWAIT;
|
|
node = atomic_read_p((void **)elmp);
|
|
} while (node == RTREE_NODE_INITIALIZING);
|
|
} else {
|
|
node = rtree->alloc(ZU(1) << rtree->levels[level].bits);
|
|
if (node == NULL)
|
|
return (NULL);
|
|
atomic_write_p((void **)elmp, node);
|
|
}
|
|
|
|
return (node);
|
|
}
|
|
|
|
rtree_node_elm_t *
|
|
rtree_subtree_read_hard(rtree_t *rtree, unsigned level)
|
|
{
|
|
|
|
return (rtree_node_init(rtree, level, &rtree->levels[level].subtree));
|
|
}
|
|
|
|
rtree_node_elm_t *
|
|
rtree_child_read_hard(rtree_t *rtree, rtree_node_elm_t *elm, unsigned level)
|
|
{
|
|
|
|
return (rtree_node_init(rtree, level, &elm->child));
|
|
}
|