xref: /dpdk/lib/eal/common/eal_common_tailqs.c (revision daa02b5cddbb8e11b31d41e2bf7bb1ae64dcae2f)
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 #include "eal_memcfg.h"
27 
28 TAILQ_HEAD(rte_tailq_elem_head, rte_tailq_elem);
29 /* local tailq list */
30 static struct rte_tailq_elem_head rte_tailq_elem_head =
31 	TAILQ_HEAD_INITIALIZER(rte_tailq_elem_head);
32 
33 /* number of tailqs registered, -1 before call to rte_eal_tailqs_init */
34 static int rte_tailqs_count = -1;
35 
36 struct rte_tailq_head *
37 rte_eal_tailq_lookup(const char *name)
38 {
39 	unsigned i;
40 	struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config;
41 
42 	if (name == NULL)
43 		return NULL;
44 
45 	for (i = 0; i < RTE_MAX_TAILQ; i++) {
46 		if (!strncmp(name, mcfg->tailq_head[i].name,
47 			     RTE_TAILQ_NAMESIZE-1))
48 			return &mcfg->tailq_head[i];
49 	}
50 
51 	return NULL;
52 }
53 
54 void
55 rte_dump_tailq(FILE *f)
56 {
57 	struct rte_mem_config *mcfg;
58 	unsigned i = 0;
59 
60 	mcfg = rte_eal_get_configuration()->mem_config;
61 
62 	rte_mcfg_tailq_read_lock();
63 	for (i = 0; i < RTE_MAX_TAILQ; i++) {
64 		const struct rte_tailq_head *tailq = &mcfg->tailq_head[i];
65 		const struct rte_tailq_entry_head *head = &tailq->tailq_head;
66 
67 		fprintf(f, "Tailq %u: qname:<%s>, tqh_first:%p, tqh_last:%p\n",
68 			i, tailq->name, head->tqh_first, head->tqh_last);
69 	}
70 	rte_mcfg_tailq_read_unlock();
71 }
72 
73 static struct rte_tailq_head *
74 rte_eal_tailq_create(const char *name)
75 {
76 	struct rte_tailq_head *head = NULL;
77 
78 	if (!rte_eal_tailq_lookup(name) &&
79 	    (rte_tailqs_count + 1 < RTE_MAX_TAILQ)) {
80 		struct rte_mem_config *mcfg;
81 
82 		mcfg = rte_eal_get_configuration()->mem_config;
83 		head = &mcfg->tailq_head[rte_tailqs_count];
84 		strlcpy(head->name, name, sizeof(head->name) - 1);
85 		TAILQ_INIT(&head->tailq_head);
86 		rte_tailqs_count++;
87 	}
88 
89 	return head;
90 }
91 
92 /* local register, used to store "early" tailqs before rte_eal_init() and to
93  * ensure secondary process only registers tailqs once. */
94 static int
95 rte_eal_tailq_local_register(struct rte_tailq_elem *t)
96 {
97 	struct rte_tailq_elem *temp;
98 
99 	TAILQ_FOREACH(temp, &rte_tailq_elem_head, next) {
100 		if (!strncmp(t->name, temp->name, sizeof(temp->name)))
101 			return -1;
102 	}
103 
104 	TAILQ_INSERT_TAIL(&rte_tailq_elem_head, t, next);
105 	return 0;
106 }
107 
108 static void
109 rte_eal_tailq_update(struct rte_tailq_elem *t)
110 {
111 	if (rte_eal_process_type() == RTE_PROC_PRIMARY) {
112 		/* primary process is the only one that creates */
113 		t->head = rte_eal_tailq_create(t->name);
114 	} else {
115 		t->head = rte_eal_tailq_lookup(t->name);
116 	}
117 }
118 
119 int
120 rte_eal_tailq_register(struct rte_tailq_elem *t)
121 {
122 	if (rte_eal_tailq_local_register(t) < 0) {
123 		RTE_LOG(ERR, EAL,
124 			"%s tailq is already registered\n", t->name);
125 		goto error;
126 	}
127 
128 	/* if a register happens after rte_eal_tailqs_init(), then we can update
129 	 * tailq head */
130 	if (rte_tailqs_count >= 0) {
131 		rte_eal_tailq_update(t);
132 		if (t->head == NULL) {
133 			RTE_LOG(ERR, EAL,
134 				"Cannot initialize tailq: %s\n", t->name);
135 			TAILQ_REMOVE(&rte_tailq_elem_head, t, next);
136 			goto error;
137 		}
138 	}
139 
140 	return 0;
141 
142 error:
143 	t->head = NULL;
144 	return -1;
145 }
146 
147 int
148 rte_eal_tailqs_init(void)
149 {
150 	struct rte_tailq_elem *t;
151 
152 	rte_tailqs_count = 0;
153 
154 	TAILQ_FOREACH(t, &rte_tailq_elem_head, next) {
155 		/* second part of register job for "early" tailqs, see
156 		 * rte_eal_tailq_register and EAL_REGISTER_TAILQ */
157 		rte_eal_tailq_update(t);
158 		if (t->head == NULL) {
159 			RTE_LOG(ERR, EAL,
160 				"Cannot initialize tailq: %s\n", t->name);
161 			/* TAILQ_REMOVE not needed, error is already fatal */
162 			goto fail;
163 		}
164 	}
165 
166 	return 0;
167 
168 fail:
169 	rte_dump_tailq(stderr);
170 	return -1;
171 }
172