lib/librte_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 <stdint.h>
   7 #include <errno.h>
   8 #include <stdio.h>
   9 #include <stdarg.h>
  10 #include <string.h>
  11 #include <inttypes.h>
  12
  13 #include <rte_memory.h>
  14 #include <rte_launch.h>
  15 #include <rte_eal.h>
  16 #include <rte_eal_memconfig.h>
  17 #include <rte_per_lcore.h>
  18 #include <rte_lcore.h>
  19 #include <rte_atomic.h>
  20 #include <rte_branch_prediction.h>
  21 #include <rte_log.h>
  22 #include <rte_string_fns.h>
  23 #include <rte_debug.h>
  24
  25 #include "eal_private.h"
  26
  27 TAILQ_HEAD(rte_tailq_elem_head, rte_tailq_elem);
  28 /* local tailq list */
  29 static struct rte_tailq_elem_head rte_tailq_elem_head =
  30         TAILQ_HEAD_INITIALIZER(rte_tailq_elem_head);
  31
  32 /* number of tailqs registered, -1 before call to rte_eal_tailqs_init */
  33 static int rte_tailqs_count = -1;
  34
  35 struct rte_tailq_head *
  36 rte_eal_tailq_lookup(const char *name)
  37 {
  38         unsigned i;
  39         struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
  40
  41         if (name == NULL)
  42                 return NULL;
  43
  44         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  45                 if (!strncmp(name, mcfg->tailq_head[i].name,
  46                              RTE_TAILQ_NAMESIZE-1))
  47                         return &mcfg->tailq_head[i];
  48         }
  49
  50         return NULL;
  51 }
  52
  53 void
  54 rte_dump_tailq(FILE *f)
  55 {
  56         struct rte_mem_config *mcfg;
  57         unsigned i = 0;
  58
  59         mcfg = rte_eal_get_configuration()->mem_config;
  60
  61         rte_rwlock_read_lock(&mcfg->qlock);
  62         for (i = 0; i < RTE_MAX_TAILQ; i++) {
  63                 const struct rte_tailq_head *tailq = &mcfg->tailq_head[i];
  64                 const struct rte_tailq_entry_head *head = &tailq->tailq_head;
  65
  66                 fprintf(f, "Tailq %u: qname:<%s>, tqh_first:%p, tqh_last:%p\n",
  67                         i, tailq->name, head->tqh_first, head->tqh_last);
  68         }
  69         rte_rwlock_read_unlock(&mcfg->qlock);
  70 }
  71
  72 static struct rte_tailq_head *
  73 rte_eal_tailq_create(const char *name)
  74 {
  75         struct rte_tailq_head *head = NULL;
  76
  77         if (!rte_eal_tailq_lookup(name) &&
  78             (rte_tailqs_count + 1 < RTE_MAX_TAILQ)) {
  79                 struct rte_mem_config *mcfg;
  80
  81                 mcfg = rte_eal_get_configuration()->mem_config;
  82                 head = &mcfg->tailq_head[rte_tailqs_count];
  83                 snprintf(head->name, sizeof(head->name) - 1, "%s", name);
  84                 TAILQ_INIT(&head->tailq_head);
  85                 rte_tailqs_count++;
  86         }
  87
  88         return head;
  89 }
  90
  91 /* local register, used to store "early" tailqs before rte_eal_init() and to
  92  * ensure secondary process only registers tailqs once. */
  93 static int
  94 rte_eal_tailq_local_register(struct rte_tailq_elem *t)
  95 {
  96         struct rte_tailq_elem *temp;
  97
  98         TAILQ_FOREACH(temp, &rte_tailq_elem_head, next) {
  99                 if (!strncmp(t->name, temp->name, sizeof(temp->name)))
 100                         return -1;
 101         }
 102
 103         TAILQ_INSERT_TAIL(&rte_tailq_elem_head, t, next);
 104         return 0;
 105 }
 106
 107 static void
 108 rte_eal_tailq_update(struct rte_tailq_elem *t)
 109 {
 110         if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
 111                 /* primary process is the only one that creates */
 112                 t->head = rte_eal_tailq_create(t->name);
 113         } else {
 114                 t->head = rte_eal_tailq_lookup(t->name);
 115         }
 116 }
 117
 118 int
 119 rte_eal_tailq_register(struct rte_tailq_elem *t)
 120 {
 121         if (rte_eal_tailq_local_register(t) < 0) {
 122                 RTE_LOG(ERR, EAL,
 123                         "%s tailq is already registered\n", t->name);
 124                 goto error;
 125         }
 126
 127         /* if a register happens after rte_eal_tailqs_init(), then we can update
 128          * tailq head */
 129         if (rte_tailqs_count >= 0) {
 130                 rte_eal_tailq_update(t);
 131                 if (t->head == NULL) {
 132                         RTE_LOG(ERR, EAL,
 133                                 "Cannot initialize tailq: %s\n", t->name);
 134                         TAILQ_REMOVE(&rte_tailq_elem_head, t, next);
 135                         goto error;
 136                 }
 137         }
 138
 139         return 0;
 140
 141 error:
 142         t->head = NULL;
 143         return -1;
 144 }
 145
 146 int
 147 rte_eal_tailqs_init(void)
 148 {
 149         struct rte_tailq_elem *t;
 150
 151         rte_tailqs_count = 0;
 152
 153         TAILQ_FOREACH(t, &rte_tailq_elem_head, next) {
 154                 /* second part of register job for "early" tailqs, see
 155                  * rte_eal_tailq_register and EAL_REGISTER_TAILQ */
 156                 rte_eal_tailq_update(t);
 157                 if (t->head == NULL) {
 158                         RTE_LOG(ERR, EAL,
 159                                 "Cannot initialize tailq: %s\n", t->name);
 160                         /* TAILQ_REMOVE not needed, error is already fatal */
 161                         goto fail;
 162                 }
 163         }
 164
 165         return 0;
 166
 167 fail:
 168         rte_dump_tailq(stderr);
 169         return -1;
 170 }