1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2019 Facebook */
3 #define _GNU_SOURCE
4 #include <sched.h>
5 #include <test_progs.h>
6
7 #define MAX_CNT 100000
8
time_get_ns(void)9 static __u64 time_get_ns(void)
10 {
11 struct timespec ts;
12
13 clock_gettime(CLOCK_MONOTONIC, &ts);
14 return ts.tv_sec * 1000000000ull + ts.tv_nsec;
15 }
16
test_task_rename(const char * prog)17 static int test_task_rename(const char *prog)
18 {
19 int i, fd, duration = 0, err;
20 char buf[] = "test\n";
21 __u64 start_time;
22
23 fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
24 if (CHECK(fd < 0, "open /proc", "err %d", errno))
25 return -1;
26 start_time = time_get_ns();
27 for (i = 0; i < MAX_CNT; i++) {
28 err = write(fd, buf, sizeof(buf));
29 if (err < 0) {
30 CHECK(err < 0, "task rename", "err %d", errno);
31 close(fd);
32 return -1;
33 }
34 }
35 printf("task_rename %s\t%lluK events per sec\n", prog,
36 MAX_CNT * 1000000ll / (time_get_ns() - start_time));
37 close(fd);
38 return 0;
39 }
40
test_run(const char * prog)41 static void test_run(const char *prog)
42 {
43 test_task_rename(prog);
44 }
45
setaffinity(void)46 static void setaffinity(void)
47 {
48 cpu_set_t cpuset;
49 int cpu = 0;
50
51 CPU_ZERO(&cpuset);
52 CPU_SET(cpu, &cpuset);
53 sched_setaffinity(0, sizeof(cpuset), &cpuset);
54 }
55
test_test_overhead(void)56 void test_test_overhead(void)
57 {
58 const char *kprobe_name = "kprobe/__set_task_comm";
59 const char *kretprobe_name = "kretprobe/__set_task_comm";
60 const char *raw_tp_name = "raw_tp/task_rename";
61 const char *fentry_name = "fentry/__set_task_comm";
62 const char *fexit_name = "fexit/__set_task_comm";
63 const char *kprobe_func = "__set_task_comm";
64 struct bpf_program *kprobe_prog, *kretprobe_prog, *raw_tp_prog;
65 struct bpf_program *fentry_prog, *fexit_prog;
66 struct bpf_object *obj;
67 struct bpf_link *link;
68 int err, duration = 0;
69
70 obj = bpf_object__open_file("./test_overhead.o", NULL);
71 if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj)))
72 return;
73
74 kprobe_prog = bpf_object__find_program_by_title(obj, kprobe_name);
75 if (CHECK(!kprobe_prog, "find_probe",
76 "prog '%s' not found\n", kprobe_name))
77 goto cleanup;
78 kretprobe_prog = bpf_object__find_program_by_title(obj, kretprobe_name);
79 if (CHECK(!kretprobe_prog, "find_probe",
80 "prog '%s' not found\n", kretprobe_name))
81 goto cleanup;
82 raw_tp_prog = bpf_object__find_program_by_title(obj, raw_tp_name);
83 if (CHECK(!raw_tp_prog, "find_probe",
84 "prog '%s' not found\n", raw_tp_name))
85 goto cleanup;
86 fentry_prog = bpf_object__find_program_by_title(obj, fentry_name);
87 if (CHECK(!fentry_prog, "find_probe",
88 "prog '%s' not found\n", fentry_name))
89 goto cleanup;
90 fexit_prog = bpf_object__find_program_by_title(obj, fexit_name);
91 if (CHECK(!fexit_prog, "find_probe",
92 "prog '%s' not found\n", fexit_name))
93 goto cleanup;
94
95 err = bpf_object__load(obj);
96 if (CHECK(err, "obj_load", "err %d\n", err))
97 goto cleanup;
98
99 setaffinity();
100
101 /* base line run */
102 test_run("base");
103
104 /* attach kprobe */
105 link = bpf_program__attach_kprobe(kprobe_prog, false /* retprobe */,
106 kprobe_func);
107 if (CHECK(IS_ERR(link), "attach_kprobe", "err %ld\n", PTR_ERR(link)))
108 goto cleanup;
109 test_run("kprobe");
110 bpf_link__destroy(link);
111
112 /* attach kretprobe */
113 link = bpf_program__attach_kprobe(kretprobe_prog, true /* retprobe */,
114 kprobe_func);
115 if (CHECK(IS_ERR(link), "attach kretprobe", "err %ld\n", PTR_ERR(link)))
116 goto cleanup;
117 test_run("kretprobe");
118 bpf_link__destroy(link);
119
120 /* attach raw_tp */
121 link = bpf_program__attach_raw_tracepoint(raw_tp_prog, "task_rename");
122 if (CHECK(IS_ERR(link), "attach fentry", "err %ld\n", PTR_ERR(link)))
123 goto cleanup;
124 test_run("raw_tp");
125 bpf_link__destroy(link);
126
127 /* attach fentry */
128 link = bpf_program__attach_trace(fentry_prog);
129 if (CHECK(IS_ERR(link), "attach fentry", "err %ld\n", PTR_ERR(link)))
130 goto cleanup;
131 test_run("fentry");
132 bpf_link__destroy(link);
133
134 /* attach fexit */
135 link = bpf_program__attach_trace(fexit_prog);
136 if (CHECK(IS_ERR(link), "attach fexit", "err %ld\n", PTR_ERR(link)))
137 goto cleanup;
138 test_run("fexit");
139 bpf_link__destroy(link);
140 cleanup:
141 bpf_object__close(obj);
142 }
143