xref: /dpdk/lib/eal/common/eal_common_thread.c (revision ae67895b507bb6af22263c79ba0d5c374b396485)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2010-2014 Intel Corporation
3  */
4 
5 #include <errno.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <pthread.h>
9 #include <sched.h>
10 #include <assert.h>
11 #include <string.h>
12 
13 #include <eal_trace_internal.h>
14 #include <rte_errno.h>
15 #include <rte_lcore.h>
16 #include <rte_log.h>
17 #include <rte_memory.h>
18 #include <rte_trace_point.h>
19 
20 #include "eal_internal_cfg.h"
21 #include "eal_private.h"
22 #include "eal_thread.h"
23 #include "eal_trace.h"
24 
25 RTE_DEFINE_PER_LCORE(unsigned int, _lcore_id) = LCORE_ID_ANY;
26 RTE_DEFINE_PER_LCORE(int, _thread_id) = -1;
27 static RTE_DEFINE_PER_LCORE(unsigned int, _socket_id) =
28 	(unsigned int)SOCKET_ID_ANY;
29 static RTE_DEFINE_PER_LCORE(rte_cpuset_t, _cpuset);
30 
rte_socket_id(void)31 unsigned rte_socket_id(void)
32 {
33 	return RTE_PER_LCORE(_socket_id);
34 }
35 
36 static int
eal_cpuset_socket_id(rte_cpuset_t * cpusetp)37 eal_cpuset_socket_id(rte_cpuset_t *cpusetp)
38 {
39 	unsigned cpu = 0;
40 	int socket_id = SOCKET_ID_ANY;
41 	int sid;
42 
43 	if (cpusetp == NULL)
44 		return SOCKET_ID_ANY;
45 
46 	do {
47 		if (!CPU_ISSET(cpu, cpusetp))
48 			continue;
49 
50 		if (socket_id == SOCKET_ID_ANY)
51 			socket_id = eal_cpu_socket_id(cpu);
52 
53 		sid = eal_cpu_socket_id(cpu);
54 		if (socket_id != sid) {
55 			socket_id = SOCKET_ID_ANY;
56 			break;
57 		}
58 
59 	} while (++cpu < CPU_SETSIZE);
60 
61 	return socket_id;
62 }
63 
64 static void
thread_update_affinity(rte_cpuset_t * cpusetp)65 thread_update_affinity(rte_cpuset_t *cpusetp)
66 {
67 	unsigned int lcore_id = rte_lcore_id();
68 
69 	/* store socket_id in TLS for quick access */
70 	RTE_PER_LCORE(_socket_id) =
71 		eal_cpuset_socket_id(cpusetp);
72 
73 	/* store cpuset in TLS for quick access */
74 	memmove(&RTE_PER_LCORE(_cpuset), cpusetp,
75 		sizeof(rte_cpuset_t));
76 
77 	if (lcore_id != (unsigned)LCORE_ID_ANY) {
78 		/* EAL thread will update lcore_config */
79 		lcore_config[lcore_id].socket_id = RTE_PER_LCORE(_socket_id);
80 		memmove(&lcore_config[lcore_id].cpuset, cpusetp,
81 			sizeof(rte_cpuset_t));
82 	}
83 }
84 
85 int
rte_thread_set_affinity(rte_cpuset_t * cpusetp)86 rte_thread_set_affinity(rte_cpuset_t *cpusetp)
87 {
88 	if (rte_thread_set_affinity_by_id(rte_thread_self(), cpusetp) != 0) {
89 		EAL_LOG(ERR, "rte_thread_set_affinity_by_id failed");
90 		return -1;
91 	}
92 
93 	thread_update_affinity(cpusetp);
94 	return 0;
95 }
96 
97 void
rte_thread_get_affinity(rte_cpuset_t * cpusetp)98 rte_thread_get_affinity(rte_cpuset_t *cpusetp)
99 {
100 	assert(cpusetp);
101 	memmove(cpusetp, &RTE_PER_LCORE(_cpuset),
102 		sizeof(rte_cpuset_t));
103 }
104 
105 int
eal_thread_dump_affinity(rte_cpuset_t * cpuset,char * str,unsigned int size)106 eal_thread_dump_affinity(rte_cpuset_t *cpuset, char *str, unsigned int size)
107 {
108 	unsigned cpu;
109 	int ret;
110 	unsigned int out = 0;
111 
112 	for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
113 		if (!CPU_ISSET(cpu, cpuset))
114 			continue;
115 
116 		ret = snprintf(str + out,
117 			       size - out, "%u,", cpu);
118 		if (ret < 0 || (unsigned)ret >= size - out) {
119 			/* string will be truncated */
120 			ret = -1;
121 			goto exit;
122 		}
123 
124 		out += ret;
125 	}
126 
127 	ret = 0;
128 exit:
129 	/* remove the last separator */
130 	if (out > 0)
131 		str[out - 1] = '\0';
132 
133 	return ret;
134 }
135 
136 int
eal_thread_dump_current_affinity(char * str,unsigned int size)137 eal_thread_dump_current_affinity(char *str, unsigned int size)
138 {
139 	rte_cpuset_t cpuset;
140 
141 	rte_thread_get_affinity(&cpuset);
142 	return eal_thread_dump_affinity(&cpuset, str, size);
143 }
144 
145 void
__rte_thread_init(unsigned int lcore_id,rte_cpuset_t * cpuset)146 __rte_thread_init(unsigned int lcore_id, rte_cpuset_t *cpuset)
147 {
148 	/* set the lcore ID in per-lcore memory area */
149 	RTE_PER_LCORE(_lcore_id) = lcore_id;
150 
151 	/* acquire system unique id */
152 	rte_gettid();
153 
154 	thread_update_affinity(cpuset);
155 
156 	__rte_trace_mem_per_thread_alloc();
157 }
158 
159 void
__rte_thread_uninit(void)160 __rte_thread_uninit(void)
161 {
162 	trace_mem_per_thread_free();
163 
164 	RTE_PER_LCORE(_lcore_id) = LCORE_ID_ANY;
165 }
166 
167 /* main loop of threads */
168 __rte_noreturn uint32_t
eal_thread_loop(void * arg)169 eal_thread_loop(void *arg)
170 {
171 	unsigned int lcore_id = (uintptr_t)arg;
172 	char cpuset[RTE_CPU_AFFINITY_STR_LEN];
173 	int ret;
174 
175 	__rte_thread_init(lcore_id, &lcore_config[lcore_id].cpuset);
176 
177 	ret = eal_thread_dump_current_affinity(cpuset, sizeof(cpuset));
178 	EAL_LOG(DEBUG, "lcore %u is ready (tid=%zx;cpuset=[%s%s])",
179 		lcore_id, rte_thread_self().opaque_id, cpuset,
180 		ret == 0 ? "" : "...");
181 
182 	rte_eal_trace_thread_lcore_ready(lcore_id, cpuset);
183 
184 	/* read on our pipe to get commands */
185 	while (1) {
186 		lcore_function_t *f;
187 		void *fct_arg;
188 
189 		eal_thread_wait_command();
190 
191 		/* Set the state to 'RUNNING'. Use release order
192 		 * since 'state' variable is used as the guard variable.
193 		 */
194 		rte_atomic_store_explicit(&lcore_config[lcore_id].state, RUNNING,
195 			rte_memory_order_release);
196 
197 		eal_thread_ack_command();
198 
199 		/* Load 'f' with acquire order to ensure that
200 		 * the memory operations from the main thread
201 		 * are accessed only after update to 'f' is visible.
202 		 * Wait till the update to 'f' is visible to the worker.
203 		 */
204 		while ((f = rte_atomic_load_explicit(&lcore_config[lcore_id].f,
205 				rte_memory_order_acquire)) == NULL)
206 			rte_pause();
207 
208 		rte_eal_trace_thread_lcore_running(lcore_id, f);
209 
210 		/* call the function and store the return value */
211 		fct_arg = lcore_config[lcore_id].arg;
212 		ret = f(fct_arg);
213 		lcore_config[lcore_id].ret = ret;
214 		lcore_config[lcore_id].f = NULL;
215 		lcore_config[lcore_id].arg = NULL;
216 
217 		/* Store the state with release order to ensure that
218 		 * the memory operations from the worker thread
219 		 * are completed before the state is updated.
220 		 * Use 'state' as the guard variable.
221 		 */
222 		rte_atomic_store_explicit(&lcore_config[lcore_id].state, WAIT,
223 			rte_memory_order_release);
224 
225 		rte_eal_trace_thread_lcore_stopped(lcore_id);
226 	}
227 
228 	/* never reached */
229 	/* return 0; */
230 }
231 
232 enum __rte_ctrl_thread_status {
233 	CTRL_THREAD_LAUNCHING, /* Yet to call pthread_create function */
234 	CTRL_THREAD_RUNNING, /* Control thread is running successfully */
235 	CTRL_THREAD_ERROR /* Control thread encountered an error */
236 };
237 
238 struct control_thread_params {
239 	rte_thread_func start_routine;
240 	void *arg;
241 	int ret;
242 	/* Control thread status.
243 	 * If the status is CTRL_THREAD_ERROR, 'ret' has the error code.
244 	 */
245 	RTE_ATOMIC(enum __rte_ctrl_thread_status) status;
246 };
247 
control_thread_init(void * arg)248 static int control_thread_init(void *arg)
249 {
250 	struct internal_config *internal_conf =
251 		eal_get_internal_configuration();
252 	rte_cpuset_t *cpuset = &internal_conf->ctrl_cpuset;
253 	struct control_thread_params *params = arg;
254 
255 	__rte_thread_init(rte_lcore_id(), cpuset);
256 	/* Set control thread socket ID to SOCKET_ID_ANY
257 	 * as control threads may be scheduled on any NUMA node.
258 	 */
259 	RTE_PER_LCORE(_socket_id) = SOCKET_ID_ANY;
260 	params->ret = rte_thread_set_affinity_by_id(rte_thread_self(), cpuset);
261 	if (params->ret != 0) {
262 		rte_atomic_store_explicit(&params->status,
263 			CTRL_THREAD_ERROR, rte_memory_order_release);
264 		return 1;
265 	}
266 
267 	rte_atomic_store_explicit(&params->status,
268 		CTRL_THREAD_RUNNING, rte_memory_order_release);
269 
270 	return 0;
271 }
272 
control_thread_start(void * arg)273 static uint32_t control_thread_start(void *arg)
274 {
275 	struct control_thread_params *params = arg;
276 	void *start_arg = params->arg;
277 	rte_thread_func start_routine = params->start_routine;
278 
279 	if (control_thread_init(arg) != 0)
280 		return 0;
281 
282 	return start_routine(start_arg);
283 }
284 
285 int
rte_thread_create_control(rte_thread_t * thread,const char * name,rte_thread_func start_routine,void * arg)286 rte_thread_create_control(rte_thread_t *thread, const char *name,
287 		rte_thread_func start_routine, void *arg)
288 {
289 	struct control_thread_params *params;
290 	enum __rte_ctrl_thread_status ctrl_thread_status;
291 	int ret;
292 
293 	params = malloc(sizeof(*params));
294 	if (params == NULL)
295 		return -ENOMEM;
296 
297 	params->start_routine = start_routine;
298 	params->arg = arg;
299 	params->ret = 0;
300 	params->status = CTRL_THREAD_LAUNCHING;
301 
302 	ret = rte_thread_create(thread, NULL, control_thread_start, params);
303 	if (ret != 0) {
304 		free(params);
305 		return -ret;
306 	}
307 
308 	if (name != NULL)
309 		rte_thread_set_name(*thread, name);
310 
311 	/* Wait for the control thread to initialize successfully */
312 	while ((ctrl_thread_status =
313 			rte_atomic_load_explicit(&params->status,
314 			rte_memory_order_acquire)) == CTRL_THREAD_LAUNCHING) {
315 		rte_delay_us_sleep(1);
316 	}
317 
318 	/* Check if the control thread encountered an error */
319 	if (ctrl_thread_status == CTRL_THREAD_ERROR) {
320 		/* ctrl thread is exiting */
321 		rte_thread_join(*thread, NULL);
322 	}
323 
324 	ret = params->ret;
325 	free(params);
326 
327 	return ret;
328 }
329 
330 static void
add_internal_prefix(char * prefixed_name,const char * name,size_t size)331 add_internal_prefix(char *prefixed_name, const char *name, size_t size)
332 {
333 	size_t prefixlen;
334 
335 	/* Check RTE_THREAD_INTERNAL_NAME_SIZE definition. */
336 	RTE_BUILD_BUG_ON(RTE_THREAD_INTERNAL_NAME_SIZE !=
337 		RTE_THREAD_NAME_SIZE - sizeof(RTE_THREAD_INTERNAL_PREFIX) + 1);
338 
339 	prefixlen = strlen(RTE_THREAD_INTERNAL_PREFIX);
340 	strlcpy(prefixed_name, RTE_THREAD_INTERNAL_PREFIX, size);
341 	strlcpy(prefixed_name + prefixlen, name, size - prefixlen);
342 }
343 
344 int
rte_thread_create_internal_control(rte_thread_t * id,const char * name,rte_thread_func func,void * arg)345 rte_thread_create_internal_control(rte_thread_t *id, const char *name,
346 		rte_thread_func func, void *arg)
347 {
348 	char prefixed_name[RTE_THREAD_NAME_SIZE];
349 
350 	add_internal_prefix(prefixed_name, name, sizeof(prefixed_name));
351 	return rte_thread_create_control(id, prefixed_name, func, arg);
352 }
353 
354 void
rte_thread_set_prefixed_name(rte_thread_t id,const char * name)355 rte_thread_set_prefixed_name(rte_thread_t id, const char *name)
356 {
357 	char prefixed_name[RTE_THREAD_NAME_SIZE];
358 
359 	add_internal_prefix(prefixed_name, name, sizeof(prefixed_name));
360 	rte_thread_set_name(id, prefixed_name);
361 }
362 
363 int
rte_thread_register(void)364 rte_thread_register(void)
365 {
366 	unsigned int lcore_id;
367 	rte_cpuset_t cpuset;
368 
369 	/* EAL init flushes all lcores, we can't register before. */
370 	if (eal_get_internal_configuration()->init_complete != 1) {
371 		EAL_LOG(DEBUG, "Called %s before EAL init.", __func__);
372 		rte_errno = EINVAL;
373 		return -1;
374 	}
375 	if (!rte_mp_disable()) {
376 		EAL_LOG(ERR, "Multiprocess in use, registering non-EAL threads is not supported.");
377 		rte_errno = EINVAL;
378 		return -1;
379 	}
380 	if (rte_thread_get_affinity_by_id(rte_thread_self(), &cpuset) != 0)
381 		CPU_ZERO(&cpuset);
382 	lcore_id = eal_lcore_non_eal_allocate();
383 	if (lcore_id >= RTE_MAX_LCORE)
384 		lcore_id = LCORE_ID_ANY;
385 	__rte_thread_init(lcore_id, &cpuset);
386 	if (lcore_id == LCORE_ID_ANY) {
387 		rte_errno = ENOMEM;
388 		return -1;
389 	}
390 	EAL_LOG(DEBUG, "Registered non-EAL thread as lcore %u.",
391 		lcore_id);
392 	return 0;
393 }
394 
395 void
rte_thread_unregister(void)396 rte_thread_unregister(void)
397 {
398 	unsigned int lcore_id = rte_lcore_id();
399 
400 	if (lcore_id != LCORE_ID_ANY)
401 		eal_lcore_non_eal_release(lcore_id);
402 	__rte_thread_uninit();
403 	if (lcore_id != LCORE_ID_ANY)
404 		EAL_LOG(DEBUG, "Unregistered non-EAL thread (was lcore %u).",
405 			lcore_id);
406 }
407 
408 int
rte_thread_attr_init(rte_thread_attr_t * attr)409 rte_thread_attr_init(rte_thread_attr_t *attr)
410 {
411 	if (attr == NULL)
412 		return EINVAL;
413 
414 	CPU_ZERO(&attr->cpuset);
415 	attr->priority = RTE_THREAD_PRIORITY_NORMAL;
416 
417 	return 0;
418 }
419 
420 int
rte_thread_attr_set_priority(rte_thread_attr_t * thread_attr,enum rte_thread_priority priority)421 rte_thread_attr_set_priority(rte_thread_attr_t *thread_attr,
422 		enum rte_thread_priority priority)
423 {
424 	if (thread_attr == NULL)
425 		return EINVAL;
426 
427 	thread_attr->priority = priority;
428 
429 	return 0;
430 }
431 
432 int
rte_thread_attr_set_affinity(rte_thread_attr_t * thread_attr,rte_cpuset_t * cpuset)433 rte_thread_attr_set_affinity(rte_thread_attr_t *thread_attr,
434 		rte_cpuset_t *cpuset)
435 {
436 	if (thread_attr == NULL)
437 		return EINVAL;
438 
439 	if (cpuset == NULL)
440 		return EINVAL;
441 
442 	thread_attr->cpuset = *cpuset;
443 
444 	return 0;
445 }
446 
447 int
rte_thread_attr_get_affinity(rte_thread_attr_t * thread_attr,rte_cpuset_t * cpuset)448 rte_thread_attr_get_affinity(rte_thread_attr_t *thread_attr,
449 		rte_cpuset_t *cpuset)
450 {
451 	if (thread_attr == NULL)
452 		return EINVAL;
453 
454 	if (cpuset == NULL)
455 		return EINVAL;
456 
457 	*cpuset = thread_attr->cpuset;
458 
459 	return 0;
460 }
461