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13#include <string.h>
14#include <pthread.h>
15
16#include <errno.h>
17#include <signal.h>
18#include <stdlib.h>
19#include <linux/compiler.h>
20#include <linux/kernel.h>
21#include <linux/zalloc.h>
22#include <sys/time.h>
23#include <perf/cpumap.h>
24
25#include "../util/stat.h"
26#include <subcmd/parse-options.h>
27#include "bench.h"
28#include "futex.h"
29
30#include <err.h>
31
32static unsigned int nthreads = 0;
33static unsigned int nsecs = 10;
34
35static unsigned int nfutexes = 1024;
36static bool fshared = false, done = false, silent = false;
37static int futex_flag = 0;
38
39struct timeval bench__start, bench__end, bench__runtime;
40static pthread_mutex_t thread_lock;
41static unsigned int threads_starting;
42static struct stats throughput_stats;
43static pthread_cond_t thread_parent, thread_worker;
44
45struct worker {
46 int tid;
47 u_int32_t *futex;
48 pthread_t thread;
49 unsigned long ops;
50};
51
52static const struct option options[] = {
53 OPT_UINTEGER('t', "threads", &nthreads, "Specify amount of threads"),
54 OPT_UINTEGER('r', "runtime", &nsecs, "Specify runtime (in seconds)"),
55 OPT_UINTEGER('f', "futexes", &nfutexes, "Specify amount of futexes per threads"),
56 OPT_BOOLEAN( 's', "silent", &silent, "Silent mode: do not display data/details"),
57 OPT_BOOLEAN( 'S', "shared", &fshared, "Use shared futexes instead of private ones"),
58 OPT_END()
59};
60
61static const char * const bench_futex_hash_usage[] = {
62 "perf bench futex hash <options>",
63 NULL
64};
65
66static void *workerfn(void *arg)
67{
68 int ret;
69 struct worker *w = (struct worker *) arg;
70 unsigned int i;
71 unsigned long ops = w->ops;
72
73 pthread_mutex_lock(&thread_lock);
74 threads_starting--;
75 if (!threads_starting)
76 pthread_cond_signal(&thread_parent);
77 pthread_cond_wait(&thread_worker, &thread_lock);
78 pthread_mutex_unlock(&thread_lock);
79
80 do {
81 for (i = 0; i < nfutexes; i++, ops++) {
82
83
84
85
86
87
88 ret = futex_wait(&w->futex[i], 1234, NULL, futex_flag);
89 if (!silent &&
90 (!ret || errno != EAGAIN || errno != EWOULDBLOCK))
91 warn("Non-expected futex return call");
92 }
93 } while (!done);
94
95 w->ops = ops;
96 return NULL;
97}
98
99static void toggle_done(int sig __maybe_unused,
100 siginfo_t *info __maybe_unused,
101 void *uc __maybe_unused)
102{
103
104 done = true;
105 gettimeofday(&bench__end, NULL);
106 timersub(&bench__end, &bench__start, &bench__runtime);
107}
108
109static void print_summary(void)
110{
111 unsigned long avg = avg_stats(&throughput_stats);
112 double stddev = stddev_stats(&throughput_stats);
113
114 printf("%sAveraged %ld operations/sec (+- %.2f%%), total secs = %d\n",
115 !silent ? "\n" : "", avg, rel_stddev_stats(stddev, avg),
116 (int)bench__runtime.tv_sec);
117}
118
119int bench_futex_hash(int argc, const char **argv)
120{
121 int ret = 0;
122 cpu_set_t cpuset;
123 struct sigaction act;
124 unsigned int i;
125 pthread_attr_t thread_attr;
126 struct worker *worker = NULL;
127 struct perf_cpu_map *cpu;
128
129 argc = parse_options(argc, argv, options, bench_futex_hash_usage, 0);
130 if (argc) {
131 usage_with_options(bench_futex_hash_usage, options);
132 exit(EXIT_FAILURE);
133 }
134
135 cpu = perf_cpu_map__new(NULL);
136 if (!cpu)
137 goto errmem;
138
139 memset(&act, 0, sizeof(act));
140 sigfillset(&act.sa_mask);
141 act.sa_sigaction = toggle_done;
142 sigaction(SIGINT, &act, NULL);
143
144 if (!nthreads)
145 nthreads = cpu->nr;
146
147 worker = calloc(nthreads, sizeof(*worker));
148 if (!worker)
149 goto errmem;
150
151 if (!fshared)
152 futex_flag = FUTEX_PRIVATE_FLAG;
153
154 printf("Run summary [PID %d]: %d threads, each operating on %d [%s] futexes for %d secs.\n\n",
155 getpid(), nthreads, nfutexes, fshared ? "shared":"private", nsecs);
156
157 init_stats(&throughput_stats);
158 pthread_mutex_init(&thread_lock, NULL);
159 pthread_cond_init(&thread_parent, NULL);
160 pthread_cond_init(&thread_worker, NULL);
161
162 threads_starting = nthreads;
163 pthread_attr_init(&thread_attr);
164 gettimeofday(&bench__start, NULL);
165 for (i = 0; i < nthreads; i++) {
166 worker[i].tid = i;
167 worker[i].futex = calloc(nfutexes, sizeof(*worker[i].futex));
168 if (!worker[i].futex)
169 goto errmem;
170
171 CPU_ZERO(&cpuset);
172 CPU_SET(cpu->map[i % cpu->nr], &cpuset);
173
174 ret = pthread_attr_setaffinity_np(&thread_attr, sizeof(cpu_set_t), &cpuset);
175 if (ret)
176 err(EXIT_FAILURE, "pthread_attr_setaffinity_np");
177
178 ret = pthread_create(&worker[i].thread, &thread_attr, workerfn,
179 (void *)(struct worker *) &worker[i]);
180 if (ret)
181 err(EXIT_FAILURE, "pthread_create");
182
183 }
184 pthread_attr_destroy(&thread_attr);
185
186 pthread_mutex_lock(&thread_lock);
187 while (threads_starting)
188 pthread_cond_wait(&thread_parent, &thread_lock);
189 pthread_cond_broadcast(&thread_worker);
190 pthread_mutex_unlock(&thread_lock);
191
192 sleep(nsecs);
193 toggle_done(0, NULL, NULL);
194
195 for (i = 0; i < nthreads; i++) {
196 ret = pthread_join(worker[i].thread, NULL);
197 if (ret)
198 err(EXIT_FAILURE, "pthread_join");
199 }
200
201
202 pthread_cond_destroy(&thread_parent);
203 pthread_cond_destroy(&thread_worker);
204 pthread_mutex_destroy(&thread_lock);
205
206 for (i = 0; i < nthreads; i++) {
207 unsigned long t = bench__runtime.tv_sec > 0 ?
208 worker[i].ops / bench__runtime.tv_sec : 0;
209 update_stats(&throughput_stats, t);
210 if (!silent) {
211 if (nfutexes == 1)
212 printf("[thread %2d] futex: %p [ %ld ops/sec ]\n",
213 worker[i].tid, &worker[i].futex[0], t);
214 else
215 printf("[thread %2d] futexes: %p ... %p [ %ld ops/sec ]\n",
216 worker[i].tid, &worker[i].futex[0],
217 &worker[i].futex[nfutexes-1], t);
218 }
219
220 zfree(&worker[i].futex);
221 }
222
223 print_summary();
224
225 free(worker);
226 free(cpu);
227 return ret;
228errmem:
229 err(EXIT_FAILURE, "calloc");
230}
231
