tetragon: Add bench_reader application

contrib/tester-progs/Makefile

@@ -15,13 +15,17 @@ PROGS = sigkill-tester \
 	uprobe-test-1 \
 	uprobe-test-2 \
 	lseek-pipe \
-	threads-tester
+	threads-tester \
+	bench-reader
 
 all: $(PROGS)
 
 %: %.c
 	$(GCC) -Wall $< -o $@
 
+bench-reader: bench-reader.c
+	$(GCC) -Wall $< -o $@ -lpthread
+
 threads-tester: threads-tester.c
 	$(GCC) -Wall -fno-inline $< -o $@ -lcap -lpthread
 

contrib/tester-progs/bench-reader.c

@@ -0,0 +1,107 @@
+
+#define _GNU_SOURCE
+
+#include <fcntl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <pthread.h>
+#include <sys/sysinfo.h>
+#include <sched.h>
+#include <time.h>
+
+struct thread_arg {
+	int id;
+	int cpu;
+	int fd;
+	size_t io_size;
+	useconds_t nsleep;
+};
+
+void *
+reader(void *arg_)
+{
+	struct thread_arg *arg = (struct thread_arg *)arg_;
+
+	cpu_set_t set;
+	CPU_ZERO(&set);
+	CPU_SET(arg->cpu, &set);
+	if (sched_setaffinity(0, sizeof(set), &set) == -1) {
+		perror("sched_setaffinity");
+		exit(1);
+	}
+
+	printf("start thread %d (cpu:%d)\n", arg->id, arg->cpu);
+	char buff[arg->io_size];
+	for (;;) {
+		read(arg->fd, buff, sizeof(buff));
+		if (arg->nsleep) {
+			const struct timespec req = {
+				.tv_nsec = arg->nsleep,
+			};
+
+			nanosleep(&req, NULL);
+		}
+	}
+	return NULL;
+}
+
+void
+usage(char *prog)
+{
+	fprintf(stderr, "Usage: %s [-t <nthreads>] [-w wait] [-s nsleep]\n", prog);
+}
+
+int
+main(int argc, char **argv)
+{
+
+	int zero_fd;
+	int wait_time = 60*10, nthreads, opt, ncpus, io_size = 10;
+	useconds_t thread_nsleep = 100;
+
+	ncpus = get_nprocs();
+	nthreads = ncpus;
+
+	while ((opt = getopt(argc, argv, "t:s:w:i:")) != -1) {
+		switch (opt) {
+			case 't':
+				nthreads = atoi(optarg);
+				break;
+			case 'w':
+				wait_time = atoi(optarg);
+				break;
+			case 's':
+				thread_nsleep = atoi(optarg);
+				break;
+			case 'i':
+				io_size = atoi(optarg);
+				break;
+			default: /* '?' */
+				usage(argv[0]);
+				exit(1);
+		}
+	}
+
+	printf("nthreads=%d wait_time=%d thread_nsleep=%d io_size=%d\n", nthreads, wait_time, thread_nsleep, io_size);
+	zero_fd = open("/dev/zero", O_RDONLY);
+	if (zero_fd < 0) {
+		perror("open");
+		exit(1);
+	}
+
+	pthread_t tids[nthreads];
+	struct thread_arg args[nthreads];
+
+	for (int i = 0; i < nthreads; i++) {
+		struct thread_arg *arg = &args[i];
+		arg->fd = zero_fd;
+		arg->nsleep = thread_nsleep;
+		arg->io_size = io_size;
+		arg->id = i;
+		arg->cpu = i % ncpus;
+		pthread_create(&tids[i], NULL, reader, arg);
+	}
+
+	sleep(wait_time);
+}