xref: /dpdk/app/test/test_mcslock.c (revision 089e5ed727a15da2729cfee9b63533dd120bd04c)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2019 Arm Limited
3  */
4 
5 #include <stdio.h>
6 #include <stdint.h>
7 #include <inttypes.h>
8 #include <string.h>
9 #include <unistd.h>
10 #include <sys/queue.h>
11 
12 #include <rte_common.h>
13 #include <rte_memory.h>
14 #include <rte_per_lcore.h>
15 #include <rte_launch.h>
16 #include <rte_eal.h>
17 #include <rte_lcore.h>
18 #include <rte_cycles.h>
19 #include <rte_mcslock.h>
20 #include <rte_atomic.h>
21 
22 #include "test.h"
23 
24 /*
25  * RTE MCS lock test
26  * =================
27  *
28  * These tests are derived from spin lock test cases.
29  *
30  * - The functional test takes all of these locks and launches the
31  *   ''test_mcslock_per_core()'' function on each core (except the master).
32  *
33  *   - The function takes the global lock, display something, then releases
34  *     the global lock on each core.
35  *
36  * - A load test is carried out, with all cores attempting to lock a single
37  *   lock multiple times.
38  */
39 
40 RTE_DEFINE_PER_LCORE(rte_mcslock_t, _ml_me);
41 RTE_DEFINE_PER_LCORE(rte_mcslock_t, _ml_try_me);
42 RTE_DEFINE_PER_LCORE(rte_mcslock_t, _ml_perf_me);
43 
44 rte_mcslock_t *p_ml;
45 rte_mcslock_t *p_ml_try;
46 rte_mcslock_t *p_ml_perf;
47 
48 static unsigned int count;
49 
50 static rte_atomic32_t synchro;
51 
52 static int
53 test_mcslock_per_core(__attribute__((unused)) void *arg)
54 {
55 	/* Per core me node. */
56 	rte_mcslock_t ml_me = RTE_PER_LCORE(_ml_me);
57 
58 	rte_mcslock_lock(&p_ml, &ml_me);
59 	printf("MCS lock taken on core %u\n", rte_lcore_id());
60 	rte_mcslock_unlock(&p_ml, &ml_me);
61 	printf("MCS lock released on core %u\n", rte_lcore_id());
62 
63 	return 0;
64 }
65 
66 static uint64_t time_count[RTE_MAX_LCORE] = {0};
67 
68 #define MAX_LOOP 1000000
69 
70 static int
71 load_loop_fn(void *func_param)
72 {
73 	uint64_t time_diff = 0, begin;
74 	uint64_t hz = rte_get_timer_hz();
75 	volatile uint64_t lcount = 0;
76 	const int use_lock = *(int *)func_param;
77 	const unsigned int lcore = rte_lcore_id();
78 
79 	/**< Per core me node. */
80 	rte_mcslock_t ml_perf_me = RTE_PER_LCORE(_ml_perf_me);
81 
82 	/* wait synchro */
83 	while (rte_atomic32_read(&synchro) == 0)
84 		;
85 
86 	begin = rte_get_timer_cycles();
87 	while (lcount < MAX_LOOP) {
88 		if (use_lock)
89 			rte_mcslock_lock(&p_ml_perf, &ml_perf_me);
90 
91 		lcount++;
92 		if (use_lock)
93 			rte_mcslock_unlock(&p_ml_perf, &ml_perf_me);
94 	}
95 	time_diff = rte_get_timer_cycles() - begin;
96 	time_count[lcore] = time_diff * 1000000 / hz;
97 	return 0;
98 }
99 
100 static int
101 test_mcslock_perf(void)
102 {
103 	unsigned int i;
104 	uint64_t total = 0;
105 	int lock = 0;
106 	const unsigned int lcore = rte_lcore_id();
107 
108 	printf("\nTest with no lock on single core...\n");
109 	rte_atomic32_set(&synchro, 1);
110 	load_loop_fn(&lock);
111 	printf("Core [%u] Cost Time = %"PRIu64" us\n",
112 			lcore, time_count[lcore]);
113 	memset(time_count, 0, sizeof(time_count));
114 
115 	printf("\nTest with lock on single core...\n");
116 	lock = 1;
117 	rte_atomic32_set(&synchro, 1);
118 	load_loop_fn(&lock);
119 	printf("Core [%u] Cost Time = %"PRIu64" us\n",
120 			lcore, time_count[lcore]);
121 	memset(time_count, 0, sizeof(time_count));
122 
123 	printf("\nTest with lock on %u cores...\n", (rte_lcore_count()));
124 
125 	rte_atomic32_set(&synchro, 0);
126 	rte_eal_mp_remote_launch(load_loop_fn, &lock, SKIP_MASTER);
127 
128 	/* start synchro and launch test on master */
129 	rte_atomic32_set(&synchro, 1);
130 	load_loop_fn(&lock);
131 
132 	rte_eal_mp_wait_lcore();
133 
134 	RTE_LCORE_FOREACH(i) {
135 		printf("Core [%u] Cost Time = %"PRIu64" us\n",
136 				i, time_count[i]);
137 		total += time_count[i];
138 	}
139 
140 	printf("Total Cost Time = %"PRIu64" us\n", total);
141 
142 	return 0;
143 }
144 
145 /*
146  * Use rte_mcslock_trylock() to trylock a mcs lock object,
147  * If it could not lock the object successfully, it would
148  * return immediately.
149  */
150 static int
151 test_mcslock_try(__attribute__((unused)) void *arg)
152 {
153 	/**< Per core me node. */
154 	rte_mcslock_t ml_me     = RTE_PER_LCORE(_ml_me);
155 	rte_mcslock_t ml_try_me = RTE_PER_LCORE(_ml_try_me);
156 
157 	/* Locked ml_try in the master lcore, so it should fail
158 	 * when trying to lock it in the slave lcore.
159 	 */
160 	if (rte_mcslock_trylock(&p_ml_try, &ml_try_me) == 0) {
161 		rte_mcslock_lock(&p_ml, &ml_me);
162 		count++;
163 		rte_mcslock_unlock(&p_ml, &ml_me);
164 	}
165 
166 	return 0;
167 }
168 
169 
170 /*
171  * Test rte_eal_get_lcore_state() in addition to mcs locks
172  * as we have "waiting" then "running" lcores.
173  */
174 static int
175 test_mcslock(void)
176 {
177 	int ret = 0;
178 	int i;
179 
180 	/* Define per core me node. */
181 	rte_mcslock_t ml_me     = RTE_PER_LCORE(_ml_me);
182 	rte_mcslock_t ml_try_me = RTE_PER_LCORE(_ml_try_me);
183 
184 	/*
185 	 * Test mcs lock & unlock on each core
186 	 */
187 
188 	/* slave cores should be waiting: print it */
189 	RTE_LCORE_FOREACH_SLAVE(i) {
190 		printf("lcore %d state: %d\n", i,
191 				(int) rte_eal_get_lcore_state(i));
192 	}
193 
194 	rte_mcslock_lock(&p_ml, &ml_me);
195 
196 	RTE_LCORE_FOREACH_SLAVE(i) {
197 		rte_eal_remote_launch(test_mcslock_per_core, NULL, i);
198 	}
199 
200 	/* slave cores should be busy: print it */
201 	RTE_LCORE_FOREACH_SLAVE(i) {
202 		printf("lcore %d state: %d\n", i,
203 				(int) rte_eal_get_lcore_state(i));
204 	}
205 
206 	rte_mcslock_unlock(&p_ml, &ml_me);
207 
208 	rte_eal_mp_wait_lcore();
209 
210 	/*
211 	 * Test if it could return immediately from try-locking a locked object.
212 	 * Here it will lock the mcs lock object first, then launch all the
213 	 * slave lcores to trylock the same mcs lock object.
214 	 * All the slave lcores should give up try-locking a locked object and
215 	 * return immediately, and then increase the "count" initialized with
216 	 * zero by one per times.
217 	 * We can check if the "count" is finally equal to the number of all
218 	 * slave lcores to see if the behavior of try-locking a locked
219 	 * mcslock object is correct.
220 	 */
221 	if (rte_mcslock_trylock(&p_ml_try, &ml_try_me) == 0)
222 		return -1;
223 
224 	count = 0;
225 	RTE_LCORE_FOREACH_SLAVE(i) {
226 		rte_eal_remote_launch(test_mcslock_try, NULL, i);
227 	}
228 	rte_eal_mp_wait_lcore();
229 	rte_mcslock_unlock(&p_ml_try, &ml_try_me);
230 
231 	/* Test is_locked API */
232 	if (rte_mcslock_is_locked(p_ml)) {
233 		printf("mcslock is locked but it should not be\n");
234 		return -1;
235 	}
236 
237 	/* Counting the locked times in each core */
238 	rte_mcslock_lock(&p_ml, &ml_me);
239 	if (count != (rte_lcore_count() - 1))
240 		ret = -1;
241 	rte_mcslock_unlock(&p_ml, &ml_me);
242 
243 	/* mcs lock perf test */
244 	if (test_mcslock_perf() < 0)
245 		return -1;
246 
247 	return ret;
248 }
249 
250 REGISTER_TEST_COMMAND(mcslock_autotest, test_mcslock);
251