/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ /*** This file is part of systemd. Copyright 2010-2014 Lennart Poettering Copyright 2014 Michal Schmidt systemd is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. systemd is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with systemd; If not, see <http://www.gnu.org/licenses/>. ***/ #include "mempool.h" #include "macro.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