xref: /dpdk/lib/eal/common/eal_common_thread.c (revision daa02b5cddbb8e11b31d41e2bf7bb1ae64dcae2f)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <stdint.h>
8 #include <unistd.h>
9 #include <pthread.h>
10 #include <signal.h>
11 #include <sched.h>
12 #include <assert.h>
13 #include <string.h>
14 
15 #include <rte_errno.h>
16 #include <rte_lcore.h>
17 #include <rte_log.h>
18 #include <rte_memory.h>
19 #include <rte_trace_point.h>
20 
21 #include "eal_internal_cfg.h"
22 #include "eal_private.h"
23 #include "eal_thread.h"
24 #include "eal_trace.h"
25 
26 RTE_DEFINE_PER_LCORE(unsigned int, _lcore_id) = LCORE_ID_ANY;
27 RTE_DEFINE_PER_LCORE(int, _thread_id) = -1;
28 static RTE_DEFINE_PER_LCORE(unsigned int, _socket_id) =
29 	(unsigned int)SOCKET_ID_ANY;
30 static RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset);
31 
32 unsigned rte_socket_id(void)
33 {
34 	return RTE_PER_LCORE(_socket_id);
35 }
36 
37 static int
38 eal_cpuset_socket_id(rte_cpuset_t *cpusetp)
39 {
40 	unsigned cpu = 0;
41 	int socket_id = SOCKET_ID_ANY;
42 	int sid;
43 
44 	if (cpusetp == NULL)
45 		return SOCKET_ID_ANY;
46 
47 	do {
48 		if (!CPU_ISSET(cpu, cpusetp))
49 			continue;
50 
51 		if (socket_id == SOCKET_ID_ANY)
52 			socket_id = eal_cpu_socket_id(cpu);
53 
54 		sid = eal_cpu_socket_id(cpu);
55 		if (socket_id != sid) {
56 			socket_id = SOCKET_ID_ANY;
57 			break;
58 		}
59 
60 	} while (++cpu < CPU_SETSIZE);
61 
62 	return socket_id;
63 }
64 
65 static void
66 thread_update_affinity(rte_cpuset_t *cpusetp)
67 {
68 	unsigned int lcore_id = rte_lcore_id();
69 
70 	/* store socket_id in TLS for quick access */
71 	RTE_PER_LCORE(_socket_id) =
72 		eal_cpuset_socket_id(cpusetp);
73 
74 	/* store cpuset in TLS for quick access */
75 	memmove(&RTE_PER_LCORE(_cpuset), cpusetp,
76 		sizeof(rte_cpuset_t));
77 
78 	if (lcore_id != (unsigned)LCORE_ID_ANY) {
79 		/* EAL thread will update lcore_config */
80 		lcore_config[lcore_id].socket_id = RTE_PER_LCORE(_socket_id);
81 		memmove(&lcore_config[lcore_id].cpuset, cpusetp,
82 			sizeof(rte_cpuset_t));
83 	}
84 }
85 
86 int
87 rte_thread_set_affinity(rte_cpuset_t *cpusetp)
88 {
89 	if (pthread_setaffinity_np(pthread_self(), sizeof(rte_cpuset_t),
90 			cpusetp) != 0) {
91 		RTE_LOG(ERR, EAL, "pthread_setaffinity_np failed\n");
92 		return -1;
93 	}
94 
95 	thread_update_affinity(cpusetp);
96 	return 0;
97 }
98 
99 void
100 rte_thread_get_affinity(rte_cpuset_t *cpusetp)
101 {
102 	assert(cpusetp);
103 	memmove(cpusetp, &RTE_PER_LCORE(_cpuset),
104 		sizeof(rte_cpuset_t));
105 }
106 
107 int
108 eal_thread_dump_affinity(rte_cpuset_t *cpuset, char *str, unsigned int size)
109 {
110 	unsigned cpu;
111 	int ret;
112 	unsigned int out = 0;
113 
114 	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
115 		if (!CPU_ISSET(cpu, cpuset))
116 			continue;
117 
118 		ret = snprintf(str + out,
119 			       size - out, "%u,", cpu);
120 		if (ret < 0 || (unsigned)ret >= size - out) {
121 			/* string will be truncated */
122 			ret = -1;
123 			goto exit;
124 		}
125 
126 		out += ret;
127 	}
128 
129 	ret = 0;
130 exit:
131 	/* remove the last separator */
132 	if (out > 0)
133 		str[out - 1] = '\0';
134 
135 	return ret;
136 }
137 
138 int
139 eal_thread_dump_current_affinity(char *str, unsigned int size)
140 {
141 	rte_cpuset_t cpuset;
142 
143 	rte_thread_get_affinity(&cpuset);
144 	return eal_thread_dump_affinity(&cpuset, str, size);
145 }
146 
147 void
148 __rte_thread_init(unsigned int lcore_id, rte_cpuset_t *cpuset)
149 {
150 	/* set the lcore ID in per-lcore memory area */
151 	RTE_PER_LCORE(_lcore_id) = lcore_id;
152 
153 	/* acquire system unique id */
154 	rte_gettid();
155 
156 	thread_update_affinity(cpuset);
157 
158 	__rte_trace_mem_per_thread_alloc();
159 }
160 
161 void
162 __rte_thread_uninit(void)
163 {
164 	trace_mem_per_thread_free();
165 
166 	RTE_PER_LCORE(_lcore_id) = LCORE_ID_ANY;
167 }
168 
169 struct rte_thread_ctrl_params {
170 	void *(*start_routine)(void *);
171 	void *arg;
172 	pthread_barrier_t configured;
173 	unsigned int refcnt;
174 };
175 
176 static void ctrl_params_free(struct rte_thread_ctrl_params *params)
177 {
178 	if (__atomic_sub_fetch(&params->refcnt, 1, __ATOMIC_ACQ_REL) == 0) {
179 		(void)pthread_barrier_destroy(&params->configured);
180 		free(params);
181 	}
182 }
183 
184 static void *ctrl_thread_init(void *arg)
185 {
186 	struct internal_config *internal_conf =
187 		eal_get_internal_configuration();
188 	rte_cpuset_t *cpuset = &internal_conf->ctrl_cpuset;
189 	struct rte_thread_ctrl_params *params = arg;
190 	void *(*start_routine)(void *);
191 	void *routine_arg = params->arg;
192 
193 	__rte_thread_init(rte_lcore_id(), cpuset);
194 
195 	pthread_barrier_wait(&params->configured);
196 	start_routine = params->start_routine;
197 	ctrl_params_free(params);
198 
199 	if (start_routine == NULL)
200 		return NULL;
201 
202 	return start_routine(routine_arg);
203 }
204 
205 int
206 rte_ctrl_thread_create(pthread_t *thread, const char *name,
207 		const pthread_attr_t *attr,
208 		void *(*start_routine)(void *), void *arg)
209 {
210 	struct internal_config *internal_conf =
211 		eal_get_internal_configuration();
212 	rte_cpuset_t *cpuset = &internal_conf->ctrl_cpuset;
213 	struct rte_thread_ctrl_params *params;
214 	int ret;
215 
216 	params = malloc(sizeof(*params));
217 	if (!params)
218 		return -ENOMEM;
219 
220 	params->start_routine = start_routine;
221 	params->arg = arg;
222 	params->refcnt = 2;
223 
224 	ret = pthread_barrier_init(&params->configured, NULL, 2);
225 	if (ret != 0)
226 		goto fail_no_barrier;
227 
228 	ret = pthread_create(thread, attr, ctrl_thread_init, (void *)params);
229 	if (ret != 0)
230 		goto fail_with_barrier;
231 
232 	if (name != NULL) {
233 		ret = rte_thread_setname(*thread, name);
234 		if (ret < 0)
235 			RTE_LOG(DEBUG, EAL,
236 				"Cannot set name for ctrl thread\n");
237 	}
238 
239 	ret = pthread_setaffinity_np(*thread, sizeof(*cpuset), cpuset);
240 	if (ret != 0)
241 		params->start_routine = NULL;
242 
243 	pthread_barrier_wait(&params->configured);
244 	ctrl_params_free(params);
245 
246 	if (ret != 0)
247 		/* start_routine has been set to NULL above; */
248 		/* ctrl thread will exit immediately */
249 		pthread_join(*thread, NULL);
250 
251 	return -ret;
252 
253 fail_with_barrier:
254 	(void)pthread_barrier_destroy(&params->configured);
255 
256 fail_no_barrier:
257 	free(params);
258 
259 	return -ret;
260 }
261 
262 int
263 rte_thread_register(void)
264 {
265 	unsigned int lcore_id;
266 	rte_cpuset_t cpuset;
267 
268 	/* EAL init flushes all lcores, we can't register before. */
269 	if (eal_get_internal_configuration()->init_complete != 1) {
270 		RTE_LOG(DEBUG, EAL, "Called %s before EAL init.\n", __func__);
271 		rte_errno = EINVAL;
272 		return -1;
273 	}
274 	if (!rte_mp_disable()) {
275 		RTE_LOG(ERR, EAL, "Multiprocess in use, registering non-EAL threads is not supported.\n");
276 		rte_errno = EINVAL;
277 		return -1;
278 	}
279 	if (pthread_getaffinity_np(pthread_self(), sizeof(cpuset),
280 			&cpuset) != 0)
281 		CPU_ZERO(&cpuset);
282 	lcore_id = eal_lcore_non_eal_allocate();
283 	if (lcore_id >= RTE_MAX_LCORE)
284 		lcore_id = LCORE_ID_ANY;
285 	__rte_thread_init(lcore_id, &cpuset);
286 	if (lcore_id == LCORE_ID_ANY) {
287 		rte_errno = ENOMEM;
288 		return -1;
289 	}
290 	RTE_LOG(DEBUG, EAL, "Registered non-EAL thread as lcore %u.\n",
291 		lcore_id);
292 	return 0;
293 }
294 
295 void
296 rte_thread_unregister(void)
297 {
298 	unsigned int lcore_id = rte_lcore_id();
299 
300 	if (lcore_id != LCORE_ID_ANY)
301 		eal_lcore_non_eal_release(lcore_id);
302 	__rte_thread_uninit();
303 	if (lcore_id != LCORE_ID_ANY)
304 		RTE_LOG(DEBUG, EAL, "Unregistered non-EAL thread (was lcore %u).\n",
305 			lcore_id);
306 }
307