This source file includes following definitions.
- print_summary
- toggle_done
- workerfn
- create_threads
- bench_futex_lock_pi
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7 #include <string.h>
8 #include <pthread.h>
9
10 #include <signal.h>
11 #include "../util/stat.h"
12 #include <subcmd/parse-options.h>
13 #include <linux/compiler.h>
14 #include <linux/kernel.h>
15 #include <linux/zalloc.h>
16 #include <errno.h>
17 #include <internal/cpumap.h>
18 #include <perf/cpumap.h>
19 #include "bench.h"
20 #include "futex.h"
21
22 #include <err.h>
23 #include <stdlib.h>
24 #include <sys/time.h>
25
26 struct worker {
27 int tid;
28 u_int32_t *futex;
29 pthread_t thread;
30 unsigned long ops;
31 };
32
33 static u_int32_t global_futex = 0;
34 static struct worker *worker;
35 static unsigned int nsecs = 10;
36 static bool silent = false, multi = false;
37 static bool done = false, fshared = false;
38 static unsigned int nthreads = 0;
39 static int futex_flag = 0;
40 struct timeval start, end, runtime;
41 static pthread_mutex_t thread_lock;
42 static unsigned int threads_starting;
43 static struct stats throughput_stats;
44 static pthread_cond_t thread_parent, thread_worker;
45
46 static const struct option options[] = {
47 OPT_UINTEGER('t', "threads", &nthreads, "Specify amount of threads"),
48 OPT_UINTEGER('r', "runtime", &nsecs, "Specify runtime (in seconds)"),
49 OPT_BOOLEAN( 'M', "multi", &multi, "Use multiple futexes"),
50 OPT_BOOLEAN( 's', "silent", &silent, "Silent mode: do not display data/details"),
51 OPT_BOOLEAN( 'S', "shared", &fshared, "Use shared futexes instead of private ones"),
52 OPT_END()
53 };
54
55 static const char * const bench_futex_lock_pi_usage[] = {
56 "perf bench futex lock-pi <options>",
57 NULL
58 };
59
60 static void print_summary(void)
61 {
62 unsigned long avg = avg_stats(&throughput_stats);
63 double stddev = stddev_stats(&throughput_stats);
64
65 printf("%sAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n",
66 !silent ? "\n" : "", avg, rel_stddev_stats(stddev, avg),
67 (int) runtime.tv_sec);
68 }
69
70 static void toggle_done(int sig __maybe_unused,
71 siginfo_t *info __maybe_unused,
72 void *uc __maybe_unused)
73 {
74
75 done = true;
76 gettimeofday(&end, NULL);
77 timersub(&end, &start, &runtime);
78 }
79
80 static void *workerfn(void *arg)
81 {
82 struct worker *w = (struct worker *) arg;
83 unsigned long ops = w->ops;
84
85 pthread_mutex_lock(&thread_lock);
86 threads_starting--;
87 if (!threads_starting)
88 pthread_cond_signal(&thread_parent);
89 pthread_cond_wait(&thread_worker, &thread_lock);
90 pthread_mutex_unlock(&thread_lock);
91
92 do {
93 int ret;
94 again:
95 ret = futex_lock_pi(w->futex, NULL, futex_flag);
96
97 if (ret) {
98 if (!silent)
99 warn("thread %d: Could not lock pi-lock for %p (%d)",
100 w->tid, w->futex, ret);
101 if (done)
102 break;
103
104 goto again;
105 }
106
107 usleep(1);
108 ret = futex_unlock_pi(w->futex, futex_flag);
109 if (ret && !silent)
110 warn("thread %d: Could not unlock pi-lock for %p (%d)",
111 w->tid, w->futex, ret);
112 ops++;
113 } while (!done);
114
115 w->ops = ops;
116 return NULL;
117 }
118
119 static void create_threads(struct worker *w, pthread_attr_t thread_attr,
120 struct perf_cpu_map *cpu)
121 {
122 cpu_set_t cpuset;
123 unsigned int i;
124
125 threads_starting = nthreads;
126
127 for (i = 0; i < nthreads; i++) {
128 worker[i].tid = i;
129
130 if (multi) {
131 worker[i].futex = calloc(1, sizeof(u_int32_t));
132 if (!worker[i].futex)
133 err(EXIT_FAILURE, "calloc");
134 } else
135 worker[i].futex = &global_futex;
136
137 CPU_ZERO(&cpuset);
138 CPU_SET(cpu->map[i % cpu->nr], &cpuset);
139
140 if (pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpuset))
141 err(EXIT_FAILURE, "pthread_attr_setaffinity_np");
142
143 if (pthread_create(&w[i].thread, &thread_attr, workerfn, &worker[i]))
144 err(EXIT_FAILURE, "pthread_create");
145 }
146 }
147
148 int bench_futex_lock_pi(int argc, const char **argv)
149 {
150 int ret = 0;
151 unsigned int i;
152 struct sigaction act;
153 pthread_attr_t thread_attr;
154 struct perf_cpu_map *cpu;
155
156 argc = parse_options(argc, argv, options, bench_futex_lock_pi_usage, 0);
157 if (argc)
158 goto err;
159
160 cpu = perf_cpu_map__new(NULL);
161 if (!cpu)
162 err(EXIT_FAILURE, "calloc");
163
164 sigfillset(&act.sa_mask);
165 act.sa_sigaction = toggle_done;
166 sigaction(SIGINT, &act, NULL);
167
168 if (!nthreads)
169 nthreads = cpu->nr;
170
171 worker = calloc(nthreads, sizeof(*worker));
172 if (!worker)
173 err(EXIT_FAILURE, "calloc");
174
175 if (!fshared)
176 futex_flag = FUTEX_PRIVATE_FLAG;
177
178 printf("Run summary [PID %d]: %d threads doing pi lock/unlock pairing for %d secs.\n\n",
179 getpid(), nthreads, nsecs);
180
181 init_stats(&throughput_stats);
182 pthread_mutex_init(&thread_lock, NULL);
183 pthread_cond_init(&thread_parent, NULL);
184 pthread_cond_init(&thread_worker, NULL);
185
186 threads_starting = nthreads;
187 pthread_attr_init(&thread_attr);
188 gettimeofday(&start, NULL);
189
190 create_threads(worker, thread_attr, cpu);
191 pthread_attr_destroy(&thread_attr);
192
193 pthread_mutex_lock(&thread_lock);
194 while (threads_starting)
195 pthread_cond_wait(&thread_parent, &thread_lock);
196 pthread_cond_broadcast(&thread_worker);
197 pthread_mutex_unlock(&thread_lock);
198
199 sleep(nsecs);
200 toggle_done(0, NULL, NULL);
201
202 for (i = 0; i < nthreads; i++) {
203 ret = pthread_join(worker[i].thread, NULL);
204 if (ret)
205 err(EXIT_FAILURE, "pthread_join");
206 }
207
208
209 pthread_cond_destroy(&thread_parent);
210 pthread_cond_destroy(&thread_worker);
211 pthread_mutex_destroy(&thread_lock);
212
213 for (i = 0; i < nthreads; i++) {
214 unsigned long t = worker[i].ops/runtime.tv_sec;
215
216 update_stats(&throughput_stats, t);
217 if (!silent)
218 printf("[thread %3d] futex: %p [ %ld ops/sec ]\n",
219 worker[i].tid, worker[i].futex, t);
220
221 if (multi)
222 zfree(&worker[i].futex);
223 }
224
225 print_summary();
226
227 free(worker);
228 return ret;
229 err:
230 usage_with_options(bench_futex_lock_pi_usage, options);
231 exit(EXIT_FAILURE);
232 }