LXR linux/tools/testing/selftests/bpf/prog_tests/test

   1// SPDX-License-Identifier: GPL-2.0-only
   2/* Copyright (c) 2019 Facebook */
   3#define _GNU_SOURCE
   4#include <sched.h>
   5#include <sys/prctl.h>
   6#include <test_progs.h>
   7
   8#define MAX_CNT 100000
   9
  10static __u64 time_get_ns(void)
  11{
  12        struct timespec ts;
  13
  14        clock_gettime(CLOCK_MONOTONIC, &ts);
  15        return ts.tv_sec * 1000000000ull + ts.tv_nsec;
  16}
  17
  18static int test_task_rename(const char *prog)
  19{
  20        int i, fd, duration = 0, err;
  21        char buf[] = "test_overhead";
  22        __u64 start_time;
  23
  24        fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
  25        if (CHECK(fd < 0, "open /proc", "err %d", errno))
  26                return -1;
  27        start_time = time_get_ns();
  28        for (i = 0; i < MAX_CNT; i++) {
  29                err = write(fd, buf, sizeof(buf));
  30                if (err < 0) {
  31                        CHECK(err < 0, "task rename", "err %d", errno);
  32                        close(fd);
  33                        return -1;
  34                }
  35        }
  36        printf("task_rename %s\t%lluK events per sec\n", prog,
  37               MAX_CNT * 1000000ll / (time_get_ns() - start_time));
  38        close(fd);
  39        return 0;
  40}
  41
  42static void test_run(const char *prog)
  43{
  44        test_task_rename(prog);
  45}
  46
  47static void setaffinity(void)
  48{
  49        cpu_set_t cpuset;
  50        int cpu = 0;
  51
  52        CPU_ZERO(&cpuset);
  53        CPU_SET(cpu, &cpuset);
  54        sched_setaffinity(0, sizeof(cpuset), &cpuset);
  55}
  56
  57void test_test_overhead(void)
  58{
  59        const char *kprobe_name = "prog1";
  60        const char *kretprobe_name = "prog2";
  61        const char *raw_tp_name = "prog3";
  62        const char *fentry_name = "prog4";
  63        const char *fexit_name = "prog5";
  64        const char *kprobe_func = "__set_task_comm";
  65        struct bpf_program *kprobe_prog, *kretprobe_prog, *raw_tp_prog;
  66        struct bpf_program *fentry_prog, *fexit_prog;
  67        struct bpf_object *obj;
  68        struct bpf_link *link;
  69        int err, duration = 0;
  70        char comm[16] = {};
  71
  72        if (CHECK_FAIL(prctl(PR_GET_NAME, comm, 0L, 0L, 0L)))
  73                return;
  74
  75        obj = bpf_object__open_file("./test_overhead.o", NULL);
  76        if (!ASSERT_OK_PTR(obj, "obj_open_file"))
  77                return;
  78
  79        kprobe_prog = bpf_object__find_program_by_name(obj, kprobe_name);
  80        if (CHECK(!kprobe_prog, "find_probe",
  81                  "prog '%s' not found\n", kprobe_name))
  82                goto cleanup;
  83        kretprobe_prog = bpf_object__find_program_by_name(obj, kretprobe_name);
  84        if (CHECK(!kretprobe_prog, "find_probe",
  85                  "prog '%s' not found\n", kretprobe_name))
  86                goto cleanup;
  87        raw_tp_prog = bpf_object__find_program_by_name(obj, raw_tp_name);
  88        if (CHECK(!raw_tp_prog, "find_probe",
  89                  "prog '%s' not found\n", raw_tp_name))
  90                goto cleanup;
  91        fentry_prog = bpf_object__find_program_by_name(obj, fentry_name);
  92        if (CHECK(!fentry_prog, "find_probe",
  93                  "prog '%s' not found\n", fentry_name))
  94                goto cleanup;
  95        fexit_prog = bpf_object__find_program_by_name(obj, fexit_name);
  96        if (CHECK(!fexit_prog, "find_probe",
  97                  "prog '%s' not found\n", fexit_name))
  98                goto cleanup;
  99        err = bpf_object__load(obj);
 100        if (CHECK(err, "obj_load", "err %d\n", err))
 101                goto cleanup;
 102
 103        setaffinity();
 104
 105        /* base line run */
 106        test_run("base");
 107
 108        /* attach kprobe */
 109        link = bpf_program__attach_kprobe(kprobe_prog, false /* retprobe */,
 110                                          kprobe_func);
 111        if (!ASSERT_OK_PTR(link, "attach_kprobe"))
 112                goto cleanup;
 113        test_run("kprobe");
 114        bpf_link__destroy(link);
 115
 116        /* attach kretprobe */
 117        link = bpf_program__attach_kprobe(kretprobe_prog, true /* retprobe */,
 118                                          kprobe_func);
 119        if (!ASSERT_OK_PTR(link, "attach_kretprobe"))
 120                goto cleanup;
 121        test_run("kretprobe");
 122        bpf_link__destroy(link);
 123
 124        /* attach raw_tp */
 125        link = bpf_program__attach_raw_tracepoint(raw_tp_prog, "task_rename");
 126        if (!ASSERT_OK_PTR(link, "attach_raw_tp"))
 127                goto cleanup;
 128        test_run("raw_tp");
 129        bpf_link__destroy(link);
 130
 131        /* attach fentry */
 132        link = bpf_program__attach_trace(fentry_prog);
 133        if (!ASSERT_OK_PTR(link, "attach_fentry"))
 134                goto cleanup;
 135        test_run("fentry");
 136        bpf_link__destroy(link);
 137
 138        /* attach fexit */
 139        link = bpf_program__attach_trace(fexit_prog);
 140        if (!ASSERT_OK_PTR(link, "attach_fexit"))
 141                goto cleanup;
 142        test_run("fexit");
 143        bpf_link__destroy(link);
 144
 145cleanup:
 146        prctl(PR_SET_NAME, comm, 0L, 0L, 0L);
 147        bpf_object__close(obj);
 148}
 149