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_launch.h>
  44 #include <rte_eal.h>
  45 #include <rte_eal_memconfig.h>
  46 #include <rte_per_lcore.h>
  47 #include <rte_lcore.h>
  48 #include <rte_atomic.h>
  49 #include <rte_branch_prediction.h>
  50 #include <rte_log.h>
  51 #include <rte_string_fns.h>
  52 #include <rte_debug.h>
  53
  54 #include "eal_private.h"
  55
  56 TAILQ_HEAD(rte_tailq_elem_head, rte_tailq_elem);
  57 /* local tailq list */
  58 static struct rte_tailq_elem_head rte_tailq_elem_head =
  59         TAILQ_HEAD_INITIALIZER(rte_tailq_elem_head);
  60
  61 /* number of tailqs registered, -1 before call to rte_eal_tailqs_init */
  62 static int rte_tailqs_count = -1;
  63
  64 struct rte_tailq_head *
  65 rte_eal_tailq_lookup(const char *name)
  66 {
  67         unsigned i;
  68         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
  69
  70         if (name == NULL)
  71                 return NULL;
  72
  73         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  74                 if (!strncmp(name, mcfg->tailq_head[i].name,
  75                              RTE_TAILQ_NAMESIZE-1))
  76                         return &mcfg->tailq_head[i];
  77         }
  78
  79         return NULL;
  80 }
  81
  82 void
  83 rte_dump_tailq(FILE *f)
  84 {
  85         struct rte_mem_config *mcfg;
  86         unsigned i = 0;
  87
  88         mcfg = rte_eal_get_configuration()->mem_config;
  89
  90         rte_rwlock_read_lock(&mcfg->qlock);
  91         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  92                 const struct rte_tailq_head *tailq = &mcfg->tailq_head[i];
  93                 const struct rte_tailq_entry_head *head = &tailq->tailq_head;
  94
  95                 fprintf(f, "Tailq %u: qname:<%s>, tqh_first:%p, tqh_last:%p\n",
  96                         i, tailq->name, head->tqh_first, head->tqh_last);
  97         }
  98         rte_rwlock_read_unlock(&mcfg->qlock);
  99 }
 100
 101 static struct rte_tailq_head *
 102 rte_eal_tailq_create(const char *name)
 103 {
 104         struct rte_tailq_head *head = NULL;
 105
 106         if (!rte_eal_tailq_lookup(name) &&
 107             (rte_tailqs_count + 1 < RTE_MAX_TAILQ)) {
 108                 struct rte_mem_config *mcfg;
 109
 110                 mcfg = rte_eal_get_configuration()->mem_config;
 111                 head = &mcfg->tailq_head[rte_tailqs_count];
 112                 snprintf(head->name, sizeof(head->name) - 1, "%s", name);
 113                 TAILQ_INIT(&head->tailq_head);
 114                 rte_tailqs_count++;
 115         }
 116
 117         return head;
 118 }
 119
 120 /* local register, used to store "early" tailqs before rte_eal_init() and to
 121  * ensure secondary process only registers tailqs once. */
 122 static int
 123 rte_eal_tailq_local_register(struct rte_tailq_elem *t)
 124 {
 125         struct rte_tailq_elem *temp;
 126
 127         TAILQ_FOREACH(temp, &rte_tailq_elem_head, next) {
 128                 if (!strncmp(t->name, temp->name, sizeof(temp->name)))
 129                         return -1;
 130         }
 131
 132         TAILQ_INSERT_TAIL(&rte_tailq_elem_head, t, next);
 133         return 0;
 134 }
 135
 136 static void
 137 rte_eal_tailq_update(struct rte_tailq_elem *t)
 138 {
 139         if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
 140                 /* primary process is the only one that creates */
 141                 t->head = rte_eal_tailq_create(t->name);
 142         } else {
 143                 t->head = rte_eal_tailq_lookup(t->name);
 144         }
 145 }
 146
 147 int
 148 rte_eal_tailq_register(struct rte_tailq_elem *t)
 149 {
 150         if (rte_eal_tailq_local_register(t) < 0) {
 151                 RTE_LOG(ERR, EAL,
 152                         "%s tailq is already registered\n", t->name);
 153                 goto error;
 154         }
 155
 156         /* if a register happens after rte_eal_tailqs_init(), then we can update
 157          * tailq head */
 158         if (rte_tailqs_count >= 0) {
 159                 rte_eal_tailq_update(t);
 160                 if (t->head == NULL) {
 161                         RTE_LOG(ERR, EAL,
 162                                 "Cannot initialize tailq: %s\n", t->name);
 163                         TAILQ_REMOVE(&rte_tailq_elem_head, t, next);
 164                         goto error;
 165                 }
 166         }
 167
 168         return 0;
 169
 170 error:
 171         t->head = NULL;
 172         return -1;
 173 }
 174
 175 int
 176 rte_eal_tailqs_init(void)
 177 {
 178         struct rte_tailq_elem *t;
 179
 180         rte_tailqs_count = 0;
 181
 182         TAILQ_FOREACH(t, &rte_tailq_elem_head, next) {
 183                 /* second part of register job for "early" tailqs, see
 184                  * rte_eal_tailq_register and EAL_REGISTER_TAILQ */
 185                 rte_eal_tailq_update(t);
 186                 if (t->head == NULL) {
 187                         RTE_LOG(ERR, EAL,
 188                                 "Cannot initialize tailq: %s\n", t->name);
 189                         /* TAILQ_REMOVE not needed, error is already fatal */
 190                         goto fail;
 191                 }
 192         }
 193
 194         return 0;
 195
 196 fail:
 197         rte_dump_tailq(stderr);
 198         return -1;
 199 }