lib/librte_eal/common/eal_common_tailqs.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <sys/queue.h>
  35 #include <stdint.h>
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <stdarg.h>
  39 #include <string.h>
  40 #include <inttypes.h>
  41
  42 #include <rte_memory.h>
  43 #include <rte_memzone.h>
  44 #include <rte_launch.h>
  45 #include <rte_eal.h>
  46 #include <rte_eal_memconfig.h>
  47 #include <rte_per_lcore.h>
  48 #include <rte_lcore.h>
  49 #include <rte_atomic.h>
  50 #include <rte_branch_prediction.h>
  51 #include <rte_log.h>
  52 #include <rte_string_fns.h>
  53 #include <rte_debug.h>
  54
  55 #include "eal_private.h"
  56
  57 TAILQ_HEAD(rte_tailq_elem_head, rte_tailq_elem);
  58 /* local tailq list */
  59 static struct rte_tailq_elem_head rte_tailq_elem_head =
  60         TAILQ_HEAD_INITIALIZER(rte_tailq_elem_head);
  61
  62 /* number of tailqs registered, -1 before call to rte_eal_tailqs_init */
  63 static int rte_tailqs_count = -1;
  64
  65 struct rte_tailq_head *
  66 rte_eal_tailq_lookup(const char *name)
  67 {
  68         unsigned i;
  69         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
  70
  71         if (name == NULL)
  72                 return NULL;
  73
  74         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  75                 if (!strncmp(name, mcfg->tailq_head[i].name,
  76                              RTE_TAILQ_NAMESIZE-1))
  77                         return &mcfg->tailq_head[i];
  78         }
  79
  80         return NULL;
  81 }
  82
  83 void
  84 rte_dump_tailq(FILE *f)
  85 {
  86         struct rte_mem_config *mcfg;
  87         unsigned i = 0;
  88
  89         mcfg = rte_eal_get_configuration()->mem_config;
  90
  91         rte_rwlock_read_lock(&mcfg->qlock);
  92         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  93                 const struct rte_tailq_head *tailq = &mcfg->tailq_head[i];
  94                 const struct rte_tailq_entry_head *head = &tailq->tailq_head;
  95
  96                 fprintf(f, "Tailq %u: qname:<%s>, tqh_first:%p, tqh_last:%p\n",
  97                         i, tailq->name, head->tqh_first, head->tqh_last);
  98         }
  99         rte_rwlock_read_unlock(&mcfg->qlock);
 100 }
 101
 102 static struct rte_tailq_head *
 103 rte_eal_tailq_create(const char *name)
 104 {
 105         struct rte_tailq_head *head = NULL;
 106
 107         if (!rte_eal_tailq_lookup(name) &&
 108             (rte_tailqs_count + 1 < RTE_MAX_TAILQ)) {
 109                 struct rte_mem_config *mcfg;
 110
 111                 mcfg = rte_eal_get_configuration()->mem_config;
 112                 head = &mcfg->tailq_head[rte_tailqs_count];
 113                 snprintf(head->name, sizeof(head->name) - 1, "%s", name);
 114                 TAILQ_INIT(&head->tailq_head);
 115                 rte_tailqs_count++;
 116         }
 117
 118         return head;
 119 }
 120
 121 /* local register, used to store "early" tailqs before rte_eal_init() and to
 122  * ensure secondary process only registers tailqs once. */
 123 static int
 124 rte_eal_tailq_local_register(struct rte_tailq_elem *t)
 125 {
 126         struct rte_tailq_elem *temp;
 127
 128         TAILQ_FOREACH(temp, &rte_tailq_elem_head, next) {
 129                 if (!strncmp(t->name, temp->name, sizeof(temp->name)))
 130                         return -1;
 131         }
 132
 133         TAILQ_INSERT_TAIL(&rte_tailq_elem_head, t, next);
 134         return 0;
 135 }
 136
 137 static void
 138 rte_eal_tailq_update(struct rte_tailq_elem *t)
 139 {
 140         if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
 141                 /* primary process is the only one that creates */
 142                 t->head = rte_eal_tailq_create(t->name);
 143         } else {
 144                 t->head = rte_eal_tailq_lookup(t->name);
 145         }
 146 }
 147
 148 int
 149 rte_eal_tailq_register(struct rte_tailq_elem *t)
 150 {
 151         if (rte_eal_tailq_local_register(t) < 0) {
 152                 RTE_LOG(ERR, EAL,
 153                         "%s tailq is already registered\n", t->name);
 154                 goto error;
 155         }
 156
 157         /* if a register happens after rte_eal_tailqs_init(), then we can update
 158          * tailq head */
 159         if (rte_tailqs_count >= 0) {
 160                 rte_eal_tailq_update(t);
 161                 if (t->head == NULL) {
 162                         RTE_LOG(ERR, EAL,
 163                                 "Cannot initialize tailq: %s\n", t->name);
 164                         TAILQ_REMOVE(&rte_tailq_elem_head, t, next);
 165                         goto error;
 166                 }
 167         }
 168
 169         return 0;
 170
 171 error:
 172         t->head = NULL;
 173         return -1;
 174 }
 175
 176 int
 177 rte_eal_tailqs_init(void)
 178 {
 179         struct rte_tailq_elem *t;
 180
 181         rte_tailqs_count = 0;
 182
 183         TAILQ_FOREACH(t, &rte_tailq_elem_head, next) {
 184                 /* second part of register job for "early" tailqs, see
 185                  * rte_eal_tailq_register and EAL_REGISTER_TAILQ */
 186                 rte_eal_tailq_update(t);
 187                 if (t->head == NULL) {
 188                         RTE_LOG(ERR, EAL,
 189                                 "Cannot initialize tailq: %s\n", t->name);
 190                         /* TAILQ_REMOVE not needed, error is already fatal */
 191                         goto fail;
 192                 }
 193         }
 194
 195         return 0;
 196
 197 fail:
 198         rte_dump_tailq(stderr);
 199         return -1;
 200 }