1 /* 2 * Copyright (c) 2012 Mellanox Technologies, Inc. All rights reserved. 3 * 4 * This software is available to you under a choice of one of two 5 * licenses. You may choose to be licensed under the terms of the GNU 6 * General Public License (GPL) Version 2, available from the file 7 * COPYING in the main directory of this source tree, or the 8 * OpenIB.org BSD license below: 9 * 10 * Redistribution and use in source and binary forms, with or 11 * without modification, are permitted provided that the following 12 * conditions are met: 13 * 14 * - Redistributions of source code must retain the above 15 * copyright notice, this list of conditions and the following 16 * disclaimer. 17 * 18 * - Redistributions in binary form must reproduce the above 19 * copyright notice, this list of conditions and the following 20 * disclaimer in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS 27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN 29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 30 * SOFTWARE. 31 */ 32 #define _GNU_SOURCE 33 #include <config.h> 34 35 #include <stdlib.h> 36 #include <pthread.h> 37 #include <string.h> 38 39 #include "mlx5.h" 40 41 struct mlx5_db_page { 42 struct mlx5_db_page *prev, *next; 43 struct mlx5_buf buf; 44 int num_db; 45 int use_cnt; 46 unsigned long free[0]; 47 }; 48 49 static struct mlx5_db_page *__add_page(struct mlx5_context *context) 50 { 51 struct mlx5_db_page *page; 52 int ps = to_mdev(context->ibv_ctx.device)->page_size; 53 int pp; 54 int i; 55 int nlong; 56 int ret; 57 58 pp = ps / context->cache_line_size; 59 nlong = (pp + 8 * sizeof(long) - 1) / (8 * sizeof(long)); 60 61 page = malloc(sizeof *page + nlong * sizeof(long)); 62 if (!page) 63 return NULL; 64 65 if (mlx5_is_extern_alloc(context)) 66 ret = mlx5_alloc_buf_extern(context, &page->buf, ps); 67 else 68 ret = mlx5_alloc_buf(&page->buf, ps, ps); 69 if (ret) { 70 free(page); 71 return NULL; 72 } 73 74 page->num_db = pp; 75 page->use_cnt = 0; 76 for (i = 0; i < nlong; ++i) 77 page->free[i] = ~0; 78 79 page->prev = NULL; 80 page->next = context->db_list; 81 context->db_list = page; 82 if (page->next) 83 page->next->prev = page; 84 85 return page; 86 } 87 88 __be32 *mlx5_alloc_dbrec(struct mlx5_context *context) 89 { 90 struct mlx5_db_page *page; 91 __be32 *db = NULL; 92 int i, j; 93 94 pthread_mutex_lock(&context->db_list_mutex); 95 96 for (page = context->db_list; page; page = page->next) 97 if (page->use_cnt < page->num_db) 98 goto found; 99 100 page = __add_page(context); 101 if (!page) 102 goto out; 103 104 found: 105 ++page->use_cnt; 106 107 for (i = 0; !page->free[i]; ++i) 108 /* nothing */; 109 110 j = ffsl(page->free[i]); 111 --j; 112 page->free[i] &= ~(1UL << j); 113 db = page->buf.buf + (i * 8 * sizeof(long) + j) * context->cache_line_size; 114 115 out: 116 pthread_mutex_unlock(&context->db_list_mutex); 117 118 return db; 119 } 120 121 void mlx5_free_db(struct mlx5_context *context, __be32 *db) 122 { 123 struct mlx5_db_page *page; 124 uintptr_t ps = to_mdev(context->ibv_ctx.device)->page_size; 125 int i; 126 127 pthread_mutex_lock(&context->db_list_mutex); 128 129 for (page = context->db_list; page; page = page->next) { 130 uintptr_t base = (uintptr_t) page->buf.buf; 131 132 if ((uintptr_t) db >= base && (uintptr_t) db - base < ps) 133 break; 134 } 135 136 if (!page) 137 goto out; 138 139 i = ((void *) db - page->buf.buf) / context->cache_line_size; 140 page->free[i / (8 * sizeof(long))] |= 1UL << (i % (8 * sizeof(long))); 141 142 if (!--page->use_cnt) { 143 if (page->prev) 144 page->prev->next = page->next; 145 else 146 context->db_list = page->next; 147 if (page->next) 148 page->next->prev = page->prev; 149 150 if (page->buf.type == MLX5_ALLOC_TYPE_EXTERNAL) 151 mlx5_free_buf_extern(context, &page->buf); 152 else 153 mlx5_free_buf(&page->buf); 154 155 free(page); 156 } 157 158 out: 159 pthread_mutex_unlock(&context->db_list_mutex); 160 } 161