diff options
Diffstat (limited to '')
| -rw-r--r-- | tools/perf/tests/bpf.c | 363 |
1 files changed, 363 insertions, 0 deletions
diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c new file mode 100644 index 000000000..df478f67b --- /dev/null +++ b/tools/perf/tests/bpf.c @@ -0,0 +1,363 @@ +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> +#include <sys/epoll.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> +#include <util/util.h> +#include <util/bpf-loader.h> +#include <util/evlist.h> +#include <linux/bpf.h> +#include <linux/filter.h> +#include <linux/kernel.h> +#include <api/fs/fs.h> +#include <bpf/bpf.h> +#include "tests.h" +#include "llvm.h" +#include "debug.h" +#define NR_ITERS 111 +#define PERF_TEST_BPF_PATH "/sys/fs/bpf/perf_test" + +#ifdef HAVE_LIBBPF_SUPPORT + +static int epoll_pwait_loop(void) +{ + int i; + + /* Should fail NR_ITERS times */ + for (i = 0; i < NR_ITERS; i++) + epoll_pwait(-(i + 1), NULL, 0, 0, NULL); + return 0; +} + +#ifdef HAVE_BPF_PROLOGUE + +static int llseek_loop(void) +{ + int fds[2], i; + + fds[0] = open("/dev/null", O_RDONLY); + fds[1] = open("/dev/null", O_RDWR); + + if (fds[0] < 0 || fds[1] < 0) + return -1; + + for (i = 0; i < NR_ITERS; i++) { + lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); + lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); + } + close(fds[0]); + close(fds[1]); + return 0; +} + +#endif + +static struct { + enum test_llvm__testcase prog_id; + const char *desc; + const char *name; + const char *msg_compile_fail; + const char *msg_load_fail; + int (*target_func)(void); + int expect_result; + bool pin; +} bpf_testcase_table[] = { + { + .prog_id = LLVM_TESTCASE_BASE, + .desc = "Basic BPF filtering", + .name = "[basic_bpf_test]", + .msg_compile_fail = "fix 'perf test LLVM' first", + .msg_load_fail = "load bpf object failed", + .target_func = &epoll_pwait_loop, + .expect_result = (NR_ITERS + 1) / 2, + }, + { + .prog_id = LLVM_TESTCASE_BASE, + .desc = "BPF pinning", + .name = "[bpf_pinning]", + .msg_compile_fail = "fix kbuild first", + .msg_load_fail = "check your vmlinux setting?", + .target_func = &epoll_pwait_loop, + .expect_result = (NR_ITERS + 1) / 2, + .pin = true, + }, +#ifdef HAVE_BPF_PROLOGUE + { + .prog_id = LLVM_TESTCASE_BPF_PROLOGUE, + .desc = "BPF prologue generation", + .name = "[bpf_prologue_test]", + .msg_compile_fail = "fix kbuild first", + .msg_load_fail = "check your vmlinux setting?", + .target_func = &llseek_loop, + .expect_result = (NR_ITERS + 1) / 4, + }, +#endif + { + .prog_id = LLVM_TESTCASE_BPF_RELOCATION, + .desc = "BPF relocation checker", + .name = "[bpf_relocation_test]", + .msg_compile_fail = "fix 'perf test LLVM' first", + .msg_load_fail = "libbpf error when dealing with relocation", + }, +}; + +static int do_test(struct bpf_object *obj, int (*func)(void), + int expect) +{ + struct record_opts opts = { + .target = { + .uid = UINT_MAX, + .uses_mmap = true, + }, + .freq = 0, + .mmap_pages = 256, + .default_interval = 1, + }; + + char pid[16]; + char sbuf[STRERR_BUFSIZE]; + struct perf_evlist *evlist; + int i, ret = TEST_FAIL, err = 0, count = 0; + + struct parse_events_state parse_state; + struct parse_events_error parse_error; + + bzero(&parse_error, sizeof(parse_error)); + bzero(&parse_state, sizeof(parse_state)); + parse_state.error = &parse_error; + INIT_LIST_HEAD(&parse_state.list); + + err = parse_events_load_bpf_obj(&parse_state, &parse_state.list, obj, NULL); + if (err || list_empty(&parse_state.list)) { + pr_debug("Failed to add events selected by BPF\n"); + return TEST_FAIL; + } + + snprintf(pid, sizeof(pid), "%d", getpid()); + pid[sizeof(pid) - 1] = '\0'; + opts.target.tid = opts.target.pid = pid; + + /* Instead of perf_evlist__new_default, don't add default events */ + evlist = perf_evlist__new(); + if (!evlist) { + pr_debug("Not enough memory to create evlist\n"); + return TEST_FAIL; + } + + err = perf_evlist__create_maps(evlist, &opts.target); + if (err < 0) { + pr_debug("Not enough memory to create thread/cpu maps\n"); + goto out_delete_evlist; + } + + perf_evlist__splice_list_tail(evlist, &parse_state.list); + evlist->nr_groups = parse_state.nr_groups; + + perf_evlist__config(evlist, &opts, NULL); + + err = perf_evlist__open(evlist); + if (err < 0) { + pr_debug("perf_evlist__open: %s\n", + str_error_r(errno, sbuf, sizeof(sbuf))); + goto out_delete_evlist; + } + + err = perf_evlist__mmap(evlist, opts.mmap_pages); + if (err < 0) { + pr_debug("perf_evlist__mmap: %s\n", + str_error_r(errno, sbuf, sizeof(sbuf))); + goto out_delete_evlist; + } + + perf_evlist__enable(evlist); + (*func)(); + perf_evlist__disable(evlist); + + for (i = 0; i < evlist->nr_mmaps; i++) { + union perf_event *event; + struct perf_mmap *md; + + md = &evlist->mmap[i]; + if (perf_mmap__read_init(md) < 0) + continue; + + while ((event = perf_mmap__read_event(md)) != NULL) { + const u32 type = event->header.type; + + if (type == PERF_RECORD_SAMPLE) + count ++; + } + perf_mmap__read_done(md); + } + + if (count != expect) { + pr_debug("BPF filter result incorrect, expected %d, got %d samples\n", expect, count); + goto out_delete_evlist; + } + + ret = TEST_OK; + +out_delete_evlist: + perf_evlist__delete(evlist); + return ret; +} + +static struct bpf_object * +prepare_bpf(void *obj_buf, size_t obj_buf_sz, const char *name) +{ + struct bpf_object *obj; + + obj = bpf__prepare_load_buffer(obj_buf, obj_buf_sz, name); + if (IS_ERR(obj)) { + pr_debug("Compile BPF program failed.\n"); + return NULL; + } + return obj; +} + +static int __test__bpf(int idx) +{ + int ret; + void *obj_buf; + size_t obj_buf_sz; + struct bpf_object *obj; + + ret = test_llvm__fetch_bpf_obj(&obj_buf, &obj_buf_sz, + bpf_testcase_table[idx].prog_id, + true, NULL); + if (ret != TEST_OK || !obj_buf || !obj_buf_sz) { + pr_debug("Unable to get BPF object, %s\n", + bpf_testcase_table[idx].msg_compile_fail); + if (idx == 0) + return TEST_SKIP; + else + return TEST_FAIL; + } + + obj = prepare_bpf(obj_buf, obj_buf_sz, + bpf_testcase_table[idx].name); + if ((!!bpf_testcase_table[idx].target_func) != (!!obj)) { + if (!obj) + pr_debug("Fail to load BPF object: %s\n", + bpf_testcase_table[idx].msg_load_fail); + else + pr_debug("Success unexpectedly: %s\n", + bpf_testcase_table[idx].msg_load_fail); + ret = TEST_FAIL; + goto out; + } + + if (obj) { + ret = do_test(obj, + bpf_testcase_table[idx].target_func, + bpf_testcase_table[idx].expect_result); + if (ret != TEST_OK) + goto out; + if (bpf_testcase_table[idx].pin) { + int err; + + if (!bpf_fs__mount()) { + pr_debug("BPF filesystem not mounted\n"); + ret = TEST_FAIL; + goto out; + } + err = mkdir(PERF_TEST_BPF_PATH, 0777); + if (err && errno != EEXIST) { + pr_debug("Failed to make perf_test dir: %s\n", + strerror(errno)); + ret = TEST_FAIL; + goto out; + } + if (bpf_object__pin(obj, PERF_TEST_BPF_PATH)) + ret = TEST_FAIL; + if (rm_rf(PERF_TEST_BPF_PATH)) + ret = TEST_FAIL; + } + } + +out: + free(obj_buf); + bpf__clear(); + return ret; +} + +int test__bpf_subtest_get_nr(void) +{ + return (int)ARRAY_SIZE(bpf_testcase_table); +} + +const char *test__bpf_subtest_get_desc(int i) +{ + if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table)) + return NULL; + return bpf_testcase_table[i].desc; +} + +static int check_env(void) +{ + int err; + unsigned int kver_int; + char license[] = "GPL"; + + struct bpf_insn insns[] = { + BPF_MOV64_IMM(BPF_REG_0, 1), + BPF_EXIT_INSN(), + }; + + err = fetch_kernel_version(&kver_int, NULL, 0); + if (err) { + pr_debug("Unable to get kernel version\n"); + return err; + } + + err = bpf_load_program(BPF_PROG_TYPE_KPROBE, insns, + sizeof(insns) / sizeof(insns[0]), + license, kver_int, NULL, 0); + if (err < 0) { + pr_err("Missing basic BPF support, skip this test: %s\n", + strerror(errno)); + return err; + } + close(err); + + return 0; +} + +int test__bpf(struct test *test __maybe_unused, int i) +{ + int err; + + if (i < 0 || i >= (int)ARRAY_SIZE(bpf_testcase_table)) + return TEST_FAIL; + + if (geteuid() != 0) { + pr_debug("Only root can run BPF test\n"); + return TEST_SKIP; + } + + if (check_env()) + return TEST_SKIP; + + err = __test__bpf(i); + return err; +} + +#else +int test__bpf_subtest_get_nr(void) +{ + return 0; +} + +const char *test__bpf_subtest_get_desc(int i __maybe_unused) +{ + return NULL; +} + +int test__bpf(struct test *test __maybe_unused, int i __maybe_unused) +{ + pr_debug("Skip BPF test because BPF support is not compiled\n"); + return TEST_SKIP; +} +#endif |