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7#define _GNU_SOURCE
8#include <sched.h>
9#include <stdio.h>
10#include <sys/types.h>
11#include <asm/unistd.h>
12#include <fcntl.h>
13#include <unistd.h>
14#include <assert.h>
15#include <sys/wait.h>
16#include <stdlib.h>
17#include <signal.h>
18#include <linux/bpf.h>
19#include <string.h>
20#include <time.h>
21#include <sys/resource.h>
22#include "libbpf.h"
23#include "bpf_load.h"
24
25#define MAX_CNT 1000000
26
27static __u64 time_get_ns(void)
28{
29 struct timespec ts;
30
31 clock_gettime(CLOCK_MONOTONIC, &ts);
32 return ts.tv_sec * 1000000000ull + ts.tv_nsec;
33}
34
35static void test_task_rename(int cpu)
36{
37 __u64 start_time;
38 char buf[] = "test\n";
39 int i, fd;
40
41 fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
42 if (fd < 0) {
43 printf("couldn't open /proc\n");
44 exit(1);
45 }
46 start_time = time_get_ns();
47 for (i = 0; i < MAX_CNT; i++)
48 write(fd, buf, sizeof(buf));
49 printf("task_rename:%d: %lld events per sec\n",
50 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
51 close(fd);
52}
53
54static void test_urandom_read(int cpu)
55{
56 __u64 start_time;
57 char buf[4];
58 int i, fd;
59
60 fd = open("/dev/urandom", O_RDONLY);
61 if (fd < 0) {
62 printf("couldn't open /dev/urandom\n");
63 exit(1);
64 }
65 start_time = time_get_ns();
66 for (i = 0; i < MAX_CNT; i++)
67 read(fd, buf, sizeof(buf));
68 printf("urandom_read:%d: %lld events per sec\n",
69 cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
70 close(fd);
71}
72
73static void loop(int cpu, int flags)
74{
75 cpu_set_t cpuset;
76
77 CPU_ZERO(&cpuset);
78 CPU_SET(cpu, &cpuset);
79 sched_setaffinity(0, sizeof(cpuset), &cpuset);
80
81 if (flags & 1)
82 test_task_rename(cpu);
83 if (flags & 2)
84 test_urandom_read(cpu);
85}
86
87static void run_perf_test(int tasks, int flags)
88{
89 pid_t pid[tasks];
90 int i;
91
92 for (i = 0; i < tasks; i++) {
93 pid[i] = fork();
94 if (pid[i] == 0) {
95 loop(i, flags);
96 exit(0);
97 } else if (pid[i] == -1) {
98 printf("couldn't spawn #%d process\n", i);
99 exit(1);
100 }
101 }
102 for (i = 0; i < tasks; i++) {
103 int status;
104
105 assert(waitpid(pid[i], &status, 0) == pid[i]);
106 assert(status == 0);
107 }
108}
109
110static void unload_progs(void)
111{
112 close(prog_fd[0]);
113 close(prog_fd[1]);
114 close(event_fd[0]);
115 close(event_fd[1]);
116}
117
118int main(int argc, char **argv)
119{
120 struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
121 char filename[256];
122 int num_cpu = 8;
123 int test_flags = ~0;
124
125 setrlimit(RLIMIT_MEMLOCK, &r);
126
127 if (argc > 1)
128 test_flags = atoi(argv[1]) ? : test_flags;
129 if (argc > 2)
130 num_cpu = atoi(argv[2]) ? : num_cpu;
131
132 if (test_flags & 0x3) {
133 printf("BASE\n");
134 run_perf_test(num_cpu, test_flags);
135 }
136
137 if (test_flags & 0xC) {
138 snprintf(filename, sizeof(filename),
139 "%s_kprobe_kern.o", argv[0]);
140 if (load_bpf_file(filename)) {
141 printf("%s", bpf_log_buf);
142 return 1;
143 }
144 printf("w/KPROBE\n");
145 run_perf_test(num_cpu, test_flags >> 2);
146 unload_progs();
147 }
148
149 if (test_flags & 0x30) {
150 snprintf(filename, sizeof(filename),
151 "%s_tp_kern.o", argv[0]);
152 if (load_bpf_file(filename)) {
153 printf("%s", bpf_log_buf);
154 return 1;
155 }
156 printf("w/TRACEPOINT\n");
157 run_perf_test(num_cpu, test_flags >> 4);
158 unload_progs();
159 }
160
161 return 0;
162}
163
