Systemd/src/basic/mempool.c
Zbigniew Jędrzejewski-Szmek 11a1589223 tree-wide: drop license boilerplate
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.

I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
2018-04-06 18:58:55 +02:00

93 lines
2.2 KiB
C

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
Copyright 2010-2014 Lennart Poettering
Copyright 2014 Michal Schmidt
***/
#include <stdint.h>
#include <stdlib.h>
#include "macro.h"
#include "mempool.h"
#include "util.h"
struct pool {
struct pool *next;
unsigned n_tiles;
unsigned n_used;
};
void* mempool_alloc_tile(struct mempool *mp) {
unsigned i;
/* When a tile is released we add it to the list and simply
* place the next pointer at its offset 0. */
assert(mp->tile_size >= sizeof(void*));
assert(mp->at_least > 0);
if (mp->freelist) {
void *r;
r = mp->freelist;
mp->freelist = * (void**) mp->freelist;
return r;
}
if (_unlikely_(!mp->first_pool) ||
_unlikely_(mp->first_pool->n_used >= mp->first_pool->n_tiles)) {
unsigned n;
size_t size;
struct pool *p;
n = mp->first_pool ? mp->first_pool->n_tiles : 0;
n = MAX(mp->at_least, n * 2);
size = PAGE_ALIGN(ALIGN(sizeof(struct pool)) + n*mp->tile_size);
n = (size - ALIGN(sizeof(struct pool))) / mp->tile_size;
p = malloc(size);
if (!p)
return NULL;
p->next = mp->first_pool;
p->n_tiles = n;
p->n_used = 0;
mp->first_pool = p;
}
i = mp->first_pool->n_used++;
return ((uint8_t*) mp->first_pool) + ALIGN(sizeof(struct pool)) + i*mp->tile_size;
}
void* mempool_alloc0_tile(struct mempool *mp) {
void *p;
p = mempool_alloc_tile(mp);
if (p)
memzero(p, mp->tile_size);
return p;
}
void mempool_free_tile(struct mempool *mp, void *p) {
* (void**) p = mp->freelist;
mp->freelist = p;
}
#ifdef VALGRIND
void mempool_drop(struct mempool *mp) {
struct pool *p = mp->first_pool;
while (p) {
struct pool *n;
n = p->next;
free(p);
p = n;
}
}
#endif