xref: /dpdk/lib/eal/common/eal_common_thread.c (revision 9ad3a41ab2a10db0059e1decdbf3ec038f348e08)
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 <pthread.h>
8 #include <sched.h>
9 #include <assert.h>
10 #include <string.h>
11 
12 #include <rte_errno.h>
13 #include <rte_lcore.h>
14 #include <rte_log.h>
15 #include <rte_memory.h>
16 #include <rte_trace_point.h>
17 
18 #include "eal_internal_cfg.h"
19 #include "eal_private.h"
20 #include "eal_thread.h"
21 #include "eal_trace.h"
22 
23 RTE_DEFINE_PER_LCORE(unsigned int, _lcore_id) = LCORE_ID_ANY;
24 RTE_DEFINE_PER_LCORE(int, _thread_id) = -1;
25 static RTE_DEFINE_PER_LCORE(unsigned int, _socket_id) =
26 	(unsigned int)SOCKET_ID_ANY;
27 static RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset);
28 
29 unsigned rte_socket_id(void)
30 {
31 	return RTE_PER_LCORE(_socket_id);
32 }
33 
34 static int
35 eal_cpuset_socket_id(rte_cpuset_t *cpusetp)
36 {
37 	unsigned cpu = 0;
38 	int socket_id = SOCKET_ID_ANY;
39 	int sid;
40 
41 	if (cpusetp == NULL)
42 		return SOCKET_ID_ANY;
43 
44 	do {
45 		if (!CPU_ISSET(cpu, cpusetp))
46 			continue;
47 
48 		if (socket_id == SOCKET_ID_ANY)
49 			socket_id = eal_cpu_socket_id(cpu);
50 
51 		sid = eal_cpu_socket_id(cpu);
52 		if (socket_id != sid) {
53 			socket_id = SOCKET_ID_ANY;
54 			break;
55 		}
56 
57 	} while (++cpu < CPU_SETSIZE);
58 
59 	return socket_id;
60 }
61 
62 static void
63 thread_update_affinity(rte_cpuset_t *cpusetp)
64 {
65 	unsigned int lcore_id = rte_lcore_id();
66 
67 	/* store socket_id in TLS for quick access */
68 	RTE_PER_LCORE(_socket_id) =
69 		eal_cpuset_socket_id(cpusetp);
70 
71 	/* store cpuset in TLS for quick access */
72 	memmove(&RTE_PER_LCORE(_cpuset), cpusetp,
73 		sizeof(rte_cpuset_t));
74 
75 	if (lcore_id != (unsigned)LCORE_ID_ANY) {
76 		/* EAL thread will update lcore_config */
77 		lcore_config[lcore_id].socket_id = RTE_PER_LCORE(_socket_id);
78 		memmove(&lcore_config[lcore_id].cpuset, cpusetp,
79 			sizeof(rte_cpuset_t));
80 	}
81 }
82 
83 int
84 rte_thread_set_affinity(rte_cpuset_t *cpusetp)
85 {
86 	if (pthread_setaffinity_np(pthread_self(), sizeof(rte_cpuset_t),
87 			cpusetp) != 0) {
88 		RTE_LOG(ERR, EAL, "pthread_setaffinity_np failed\n");
89 		return -1;
90 	}
91 
92 	thread_update_affinity(cpusetp);
93 	return 0;
94 }
95 
96 void
97 rte_thread_get_affinity(rte_cpuset_t *cpusetp)
98 {
99 	assert(cpusetp);
100 	memmove(cpusetp, &RTE_PER_LCORE(_cpuset),
101 		sizeof(rte_cpuset_t));
102 }
103 
104 int
105 eal_thread_dump_affinity(rte_cpuset_t *cpuset, char *str, unsigned int size)
106 {
107 	unsigned cpu;
108 	int ret;
109 	unsigned int out = 0;
110 
111 	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
112 		if (!CPU_ISSET(cpu, cpuset))
113 			continue;
114 
115 		ret = snprintf(str + out,
116 			       size - out, "%u,", cpu);
117 		if (ret < 0 || (unsigned)ret >= size - out) {
118 			/* string will be truncated */
119 			ret = -1;
120 			goto exit;
121 		}
122 
123 		out += ret;
124 	}
125 
126 	ret = 0;
127 exit:
128 	/* remove the last separator */
129 	if (out > 0)
130 		str[out - 1] = '\0';
131 
132 	return ret;
133 }
134 
135 int
136 eal_thread_dump_current_affinity(char *str, unsigned int size)
137 {
138 	rte_cpuset_t cpuset;
139 
140 	rte_thread_get_affinity(&cpuset);
141 	return eal_thread_dump_affinity(&cpuset, str, size);
142 }
143 
144 void
145 __rte_thread_init(unsigned int lcore_id, rte_cpuset_t *cpuset)
146 {
147 	/* set the lcore ID in per-lcore memory area */
148 	RTE_PER_LCORE(_lcore_id) = lcore_id;
149 
150 	/* acquire system unique id */
151 	rte_gettid();
152 
153 	thread_update_affinity(cpuset);
154 
155 	__rte_trace_mem_per_thread_alloc();
156 }
157 
158 void
159 __rte_thread_uninit(void)
160 {
161 	trace_mem_per_thread_free();
162 
163 	RTE_PER_LCORE(_lcore_id) = LCORE_ID_ANY;
164 }
165 
166 enum __rte_ctrl_thread_status {
167 	CTRL_THREAD_LAUNCHING, /* Yet to call pthread_create function */
168 	CTRL_THREAD_RUNNING, /* Control thread is running successfully */
169 	CTRL_THREAD_ERROR /* Control thread encountered an error */
170 };
171 
172 struct rte_thread_ctrl_params {
173 	void *(*start_routine)(void *);
174 	void *arg;
175 	int ret;
176 	/* Control thread status.
177 	 * If the status is CTRL_THREAD_ERROR, 'ret' has the error code.
178 	 */
179 	enum __rte_ctrl_thread_status ctrl_thread_status;
180 };
181 
182 static void *ctrl_thread_init(void *arg)
183 {
184 	struct internal_config *internal_conf =
185 		eal_get_internal_configuration();
186 	rte_cpuset_t *cpuset = &internal_conf->ctrl_cpuset;
187 	struct rte_thread_ctrl_params *params = arg;
188 	void *(*start_routine)(void *) = params->start_routine;
189 	void *routine_arg = params->arg;
190 
191 	__rte_thread_init(rte_lcore_id(), cpuset);
192 	params->ret = pthread_setaffinity_np(pthread_self(), sizeof(*cpuset),
193 		cpuset);
194 	if (params->ret != 0) {
195 		__atomic_store_n(&params->ctrl_thread_status,
196 			CTRL_THREAD_ERROR, __ATOMIC_RELEASE);
197 		return NULL;
198 	}
199 
200 	__atomic_store_n(&params->ctrl_thread_status,
201 		CTRL_THREAD_RUNNING, __ATOMIC_RELEASE);
202 
203 	return start_routine(routine_arg);
204 }
205 
206 int
207 rte_ctrl_thread_create(pthread_t *thread, const char *name,
208 		const pthread_attr_t *attr,
209 		void *(*start_routine)(void *), void *arg)
210 {
211 	struct rte_thread_ctrl_params *params;
212 	enum __rte_ctrl_thread_status ctrl_thread_status;
213 	int ret;
214 
215 	params = malloc(sizeof(*params));
216 	if (!params)
217 		return -ENOMEM;
218 
219 	params->start_routine = start_routine;
220 	params->arg = arg;
221 	params->ret = 0;
222 	params->ctrl_thread_status = CTRL_THREAD_LAUNCHING;
223 
224 	ret = pthread_create(thread, attr, ctrl_thread_init, (void *)params);
225 	if (ret != 0) {
226 		free(params);
227 		return -ret;
228 	}
229 
230 	if (name != NULL) {
231 		ret = rte_thread_setname(*thread, name);
232 		if (ret < 0)
233 			RTE_LOG(DEBUG, EAL,
234 				"Cannot set name for ctrl thread\n");
235 	}
236 
237 	/* Wait for the control thread to initialize successfully */
238 	while ((ctrl_thread_status =
239 			__atomic_load_n(&params->ctrl_thread_status,
240 			__ATOMIC_ACQUIRE)) == CTRL_THREAD_LAUNCHING) {
241 		/* Yield the CPU. Using sched_yield call requires maintaining
242 		 * another implementation for Windows as sched_yield is not
243 		 * supported on Windows.
244 		 */
245 		rte_delay_us_sleep(1);
246 	}
247 
248 	/* Check if the control thread encountered an error */
249 	if (ctrl_thread_status == CTRL_THREAD_ERROR) {
250 		/* ctrl thread is exiting */
251 		pthread_join(*thread, NULL);
252 	}
253 
254 	ret = params->ret;
255 	free(params);
256 
257 	return -ret;
258 }
259 
260 int
261 rte_thread_register(void)
262 {
263 	unsigned int lcore_id;
264 	rte_cpuset_t cpuset;
265 
266 	/* EAL init flushes all lcores, we can't register before. */
267 	if (eal_get_internal_configuration()->init_complete != 1) {
268 		RTE_LOG(DEBUG, EAL, "Called %s before EAL init.\n", __func__);
269 		rte_errno = EINVAL;
270 		return -1;
271 	}
272 	if (!rte_mp_disable()) {
273 		RTE_LOG(ERR, EAL, "Multiprocess in use, registering non-EAL threads is not supported.\n");
274 		rte_errno = EINVAL;
275 		return -1;
276 	}
277 	if (pthread_getaffinity_np(pthread_self(), sizeof(cpuset),
278 			&cpuset) != 0)
279 		CPU_ZERO(&cpuset);
280 	lcore_id = eal_lcore_non_eal_allocate();
281 	if (lcore_id >= RTE_MAX_LCORE)
282 		lcore_id = LCORE_ID_ANY;
283 	__rte_thread_init(lcore_id, &cpuset);
284 	if (lcore_id == LCORE_ID_ANY) {
285 		rte_errno = ENOMEM;
286 		return -1;
287 	}
288 	RTE_LOG(DEBUG, EAL, "Registered non-EAL thread as lcore %u.\n",
289 		lcore_id);
290 	return 0;
291 }
292 
293 void
294 rte_thread_unregister(void)
295 {
296 	unsigned int lcore_id = rte_lcore_id();
297 
298 	if (lcore_id != LCORE_ID_ANY)
299 		eal_lcore_non_eal_release(lcore_id);
300 	__rte_thread_uninit();
301 	if (lcore_id != LCORE_ID_ANY)
302 		RTE_LOG(DEBUG, EAL, "Unregistered non-EAL thread (was lcore %u).\n",
303 			lcore_id);
304 }
305