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// SPDX-License-Identifier: GPL-2.0-only
/* Copyright (c) 2019 Facebook */
#define _GNU_SOURCE
#include <sched.h>
#include <test_progs.h>
#define MAX_CNT 100000
static __u64 time_get_ns(void)
{
struct timespec ts;
clock_gettime(CLOCK_MONOTONIC, &ts);
return ts.tv_sec * 1000000000ull + ts.tv_nsec;
}
static int test_task_rename(const char *prog)
{
int i, fd, duration = 0, err;
char buf[] = "test\n";
__u64 start_time;
fd = open("/proc/self/comm", O_WRONLY|O_TRUNC);
if (CHECK(fd < 0, "open /proc", "err %d", errno))
return -1;
start_time = time_get_ns();
for (i = 0; i < MAX_CNT; i++) {
err = write(fd, buf, sizeof(buf));
if (err < 0) {
CHECK(err < 0, "task rename", "err %d", errno);
close(fd);
return -1;
}
}
printf("task_rename %s\t%lluK events per sec\n", prog,
MAX_CNT * 1000000ll / (time_get_ns() - start_time));
close(fd);
return 0;
}
static void test_run(const char *prog)
{
test_task_rename(prog);
}
static void setaffinity(void)
{
cpu_set_t cpuset;
int cpu = 0;
CPU_ZERO(&cpuset);
CPU_SET(cpu, &cpuset);
sched_setaffinity(0, sizeof(cpuset), &cpuset);
}
void test_test_overhead(void)
{
const char *kprobe_name = "kprobe/__set_task_comm";
const char *kretprobe_name = "kretprobe/__set_task_comm";
const char *raw_tp_name = "raw_tp/task_rename";
const char *fentry_name = "fentry/__set_task_comm";
const char *fexit_name = "fexit/__set_task_comm";
const char *kprobe_func = "__set_task_comm";
struct bpf_program *kprobe_prog, *kretprobe_prog, *raw_tp_prog;
struct bpf_program *fentry_prog, *fexit_prog;
struct bpf_object *obj;
struct bpf_link *link;
int err, duration = 0;
obj = bpf_object__open_file("./test_overhead.o", NULL);
if (CHECK(IS_ERR(obj), "obj_open_file", "err %ld\n", PTR_ERR(obj)))
return;
kprobe_prog = bpf_object__find_program_by_title(obj, kprobe_name);
if (CHECK(!kprobe_prog, "find_probe",
"prog '%s' not found\n", kprobe_name))
goto cleanup;
kretprobe_prog = bpf_object__find_program_by_title(obj, kretprobe_name);
if (CHECK(!kretprobe_prog, "find_probe",
"prog '%s' not found\n", kretprobe_name))
goto cleanup;
raw_tp_prog = bpf_object__find_program_by_title(obj, raw_tp_name);
if (CHECK(!raw_tp_prog, "find_probe",
"prog '%s' not found\n", raw_tp_name))
goto cleanup;
fentry_prog = bpf_object__find_program_by_title(obj, fentry_name);
if (CHECK(!fentry_prog, "find_probe",
"prog '%s' not found\n", fentry_name))
goto cleanup;
fexit_prog = bpf_object__find_program_by_title(obj, fexit_name);
if (CHECK(!fexit_prog, "find_probe",
"prog '%s' not found\n", fexit_name))
goto cleanup;
err = bpf_object__load(obj);
if (CHECK(err, "obj_load", "err %d\n", err))
goto cleanup;
setaffinity();
/* base line run */
test_run("base");
/* attach kprobe */
link = bpf_program__attach_kprobe(kprobe_prog, false /* retprobe */,
kprobe_func);
if (CHECK(IS_ERR(link), "attach_kprobe", "err %ld\n", PTR_ERR(link)))
goto cleanup;
test_run("kprobe");
bpf_link__destroy(link);
/* attach kretprobe */
link = bpf_program__attach_kprobe(kretprobe_prog, true /* retprobe */,
kprobe_func);
if (CHECK(IS_ERR(link), "attach kretprobe", "err %ld\n", PTR_ERR(link)))
goto cleanup;
test_run("kretprobe");
bpf_link__destroy(link);
/* attach raw_tp */
link = bpf_program__attach_raw_tracepoint(raw_tp_prog, "task_rename");
if (CHECK(IS_ERR(link), "attach fentry", "err %ld\n", PTR_ERR(link)))
goto cleanup;
test_run("raw_tp");
bpf_link__destroy(link);
/* attach fentry */
link = bpf_program__attach_trace(fentry_prog);
if (CHECK(IS_ERR(link), "attach fentry", "err %ld\n", PTR_ERR(link)))
goto cleanup;
test_run("fentry");
bpf_link__destroy(link);
/* attach fexit */
link = bpf_program__attach_trace(fexit_prog);
if (CHECK(IS_ERR(link), "attach fexit", "err %ld\n", PTR_ERR(link)))
goto cleanup;
test_run("fexit");
bpf_link__destroy(link);
cleanup:
bpf_object__close(obj);
}
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