lib/eal/common/eal_common_tailqs.c

   1 /* SPDX-License-Identifier: BSD-3-Clause
   2  * Copyright(c) 2010-2014 Intel Corporation
   3  */
   4
   5 #include <sys/queue.h>
   6 #include <stdio.h>
   7 #include <string.h>
   8
   9 #include <rte_eal.h>
  10 #include <rte_eal_memconfig.h>
  11 #include <rte_log.h>
  12 #include <rte_string_fns.h>
  13
  14 #include "eal_private.h"
  15 #include "eal_memcfg.h"
  16
  17 TAILQ_HEAD(rte_tailq_elem_head, rte_tailq_elem);
  18 /* local tailq list */
  19 static struct rte_tailq_elem_head rte_tailq_elem_head =
  20         TAILQ_HEAD_INITIALIZER(rte_tailq_elem_head);
  21
  22 /* number of tailqs registered, -1 before call to rte_eal_tailqs_init */
  23 static int rte_tailqs_count = -1;
  24
  25 struct rte_tailq_head *
  26 rte_eal_tailq_lookup(const char *name)
  27 {
  28         unsigned i;
  29         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
  30
  31         if (name == NULL)
  32                 return NULL;
  33
  34         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  35                 if (!strncmp(name, mcfg->tailq_head[i].name,
  36                              RTE_TAILQ_NAMESIZE-1))
  37                         return &mcfg->tailq_head[i];
  38         }
  39
  40         return NULL;
  41 }
  42
  43 void
  44 rte_dump_tailq(FILE *f)
  45 {
  46         struct rte_mem_config *mcfg;
  47         unsigned i = 0;
  48
  49         mcfg = rte_eal_get_configuration()->mem_config;
  50
  51         rte_mcfg_tailq_read_lock();
  52         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  53                 const struct rte_tailq_head *tailq = &mcfg->tailq_head[i];
  54                 const struct rte_tailq_entry_head *head = &tailq->tailq_head;
  55
  56                 fprintf(f, "Tailq %u: qname:<%s>, tqh_first:%p, tqh_last:%p\n",
  57                         i, tailq->name, head->tqh_first, head->tqh_last);
  58         }
  59         rte_mcfg_tailq_read_unlock();
  60 }
  61
  62 static struct rte_tailq_head *
  63 rte_eal_tailq_create(const char *name)
  64 {
  65         struct rte_tailq_head *head = NULL;
  66
  67         if (!rte_eal_tailq_lookup(name) &&
  68             (rte_tailqs_count + 1 < RTE_MAX_TAILQ)) {
  69                 struct rte_mem_config *mcfg;
  70
  71                 mcfg = rte_eal_get_configuration()->mem_config;
  72                 head = &mcfg->tailq_head[rte_tailqs_count];
  73                 strlcpy(head->name, name, sizeof(head->name) - 1);
  74                 TAILQ_INIT(&head->tailq_head);
  75                 rte_tailqs_count++;
  76         }
  77
  78         return head;
  79 }
  80
  81 /* local register, used to store "early" tailqs before rte_eal_init() and to
  82  * ensure secondary process only registers tailqs once. */
  83 static int
  84 rte_eal_tailq_local_register(struct rte_tailq_elem *t)
  85 {
  86         struct rte_tailq_elem *temp;
  87
  88         TAILQ_FOREACH(temp, &rte_tailq_elem_head, next) {
  89                 if (!strncmp(t->name, temp->name, sizeof(temp->name)))
  90                         return -1;
  91         }
  92
  93         TAILQ_INSERT_TAIL(&rte_tailq_elem_head, t, next);
  94         return 0;
  95 }
  96
  97 static void
  98 rte_eal_tailq_update(struct rte_tailq_elem *t)
  99 {
 100         if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
 101                 /* primary process is the only one that creates */
 102                 t->head = rte_eal_tailq_create(t->name);
 103         } else {
 104                 t->head = rte_eal_tailq_lookup(t->name);
 105         }
 106 }
 107
 108 int
 109 rte_eal_tailq_register(struct rte_tailq_elem *t)
 110 {
 111         if (rte_eal_tailq_local_register(t) < 0) {
 112                 RTE_LOG(ERR, EAL,
 113                         "%s tailq is already registered\n", t->name);
 114                 goto error;
 115         }
 116
 117         /* if a register happens after rte_eal_tailqs_init(), then we can update
 118          * tailq head */
 119         if (rte_tailqs_count >= 0) {
 120                 rte_eal_tailq_update(t);
 121                 if (t->head == NULL) {
 122                         RTE_LOG(ERR, EAL,
 123                                 "Cannot initialize tailq: %s\n", t->name);
 124                         TAILQ_REMOVE(&rte_tailq_elem_head, t, next);
 125                         goto error;
 126                 }
 127         }
 128
 129         return 0;
 130
 131 error:
 132         t->head = NULL;
 133         return -1;
 134 }
 135
 136 int
 137 rte_eal_tailqs_init(void)
 138 {
 139         struct rte_tailq_elem *t;
 140
 141         rte_tailqs_count = 0;
 142
 143         TAILQ_FOREACH(t, &rte_tailq_elem_head, next) {
 144                 /* second part of register job for "early" tailqs, see
 145                  * rte_eal_tailq_register and EAL_REGISTER_TAILQ */
 146                 rte_eal_tailq_update(t);
 147                 if (t->head == NULL) {
 148                         RTE_LOG(ERR, EAL,
 149                                 "Cannot initialize tailq: %s\n", t->name);
 150                         /* TAILQ_REMOVE not needed, error is already fatal */
 151                         goto fail;
 152                 }
 153         }
 154
 155         return 0;
 156
 157 fail:
 158         rte_dump_tailq(stderr);
 159         return -1;
 160 }