diff options
Diffstat (limited to 'tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c')
| -rw-r--r-- | tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c | 159 |
1 files changed, 152 insertions, 7 deletions
diff --git a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c index b9876b55fc0c..586dc52d6fb9 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -2,6 +2,9 @@ #include <test_progs.h> #include "kprobe_multi.skel.h" #include "trace_helpers.h" +#include "kprobe_multi_empty.skel.h" +#include "bpf/libbpf_internal.h" +#include "bpf/hashmap.h" static void kprobe_multi_test_run(struct kprobe_multi *skel, bool test_return) { @@ -140,14 +143,14 @@ test_attach_api(const char *pattern, struct bpf_kprobe_multi_opts *opts) goto cleanup; skel->bss->pid = getpid(); - link1 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link1 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, pattern, opts); if (!ASSERT_OK_PTR(link1, "bpf_program__attach_kprobe_multi_opts")) goto cleanup; if (opts) { opts->retprobe = true; - link2 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kretprobe, + link2 = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kretprobe_manual, pattern, opts); if (!ASSERT_OK_PTR(link2, "bpf_program__attach_kprobe_multi_opts")) goto cleanup; @@ -232,7 +235,7 @@ static void test_attach_api_fails(void) skel->bss->pid = getpid(); /* fail_1 - pattern and opts NULL */ - link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, NULL, NULL); if (!ASSERT_ERR_PTR(link, "fail_1")) goto cleanup; @@ -246,7 +249,7 @@ static void test_attach_api_fails(void) opts.cnt = ARRAY_SIZE(syms); opts.cookies = NULL; - link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, NULL, &opts); if (!ASSERT_ERR_PTR(link, "fail_2")) goto cleanup; @@ -260,7 +263,7 @@ static void test_attach_api_fails(void) opts.cnt = ARRAY_SIZE(syms); opts.cookies = NULL; - link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, "ksys_*", &opts); if (!ASSERT_ERR_PTR(link, "fail_3")) goto cleanup; @@ -274,7 +277,7 @@ static void test_attach_api_fails(void) opts.cnt = ARRAY_SIZE(syms); opts.cookies = NULL; - link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, "ksys_*", &opts); if (!ASSERT_ERR_PTR(link, "fail_4")) goto cleanup; @@ -288,7 +291,7 @@ static void test_attach_api_fails(void) opts.cnt = 0; opts.cookies = cookies; - link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe, + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_manual, "ksys_*", &opts); if (!ASSERT_ERR_PTR(link, "fail_5")) goto cleanup; @@ -301,6 +304,146 @@ cleanup: kprobe_multi__destroy(skel); } +static inline __u64 get_time_ns(void) +{ + struct timespec t; + + clock_gettime(CLOCK_MONOTONIC, &t); + return (__u64) t.tv_sec * 1000000000 + t.tv_nsec; +} + +static size_t symbol_hash(const void *key, void *ctx __maybe_unused) +{ + return str_hash((const char *) key); +} + +static bool symbol_equal(const void *key1, const void *key2, void *ctx __maybe_unused) +{ + return strcmp((const char *) key1, (const char *) key2) == 0; +} + +static int get_syms(char ***symsp, size_t *cntp) +{ + size_t cap = 0, cnt = 0, i; + char *name, **syms = NULL; + struct hashmap *map; + char buf[256]; + FILE *f; + int err; + + /* + * The available_filter_functions contains many duplicates, + * but other than that all symbols are usable in kprobe multi + * interface. + * Filtering out duplicates by using hashmap__add, which won't + * add existing entry. + */ + f = fopen("/sys/kernel/debug/tracing/available_filter_functions", "r"); + if (!f) + return -EINVAL; + + map = hashmap__new(symbol_hash, symbol_equal, NULL); + if (IS_ERR(map)) { + err = libbpf_get_error(map); + goto error; + } + + while (fgets(buf, sizeof(buf), f)) { + /* skip modules */ + if (strchr(buf, '[')) + continue; + if (sscanf(buf, "%ms$*[^\n]\n", &name) != 1) + continue; + /* + * We attach to almost all kernel functions and some of them + * will cause 'suspicious RCU usage' when fprobe is attached + * to them. Filter out the current culprits - arch_cpu_idle + * and rcu_* functions. + */ + if (!strcmp(name, "arch_cpu_idle")) + continue; + if (!strncmp(name, "rcu_", 4)) + continue; + err = hashmap__add(map, name, NULL); + if (err) { + free(name); + if (err == -EEXIST) + continue; + goto error; + } + err = libbpf_ensure_mem((void **) &syms, &cap, + sizeof(*syms), cnt + 1); + if (err) { + free(name); + goto error; + } + syms[cnt] = name; + cnt++; + } + + *symsp = syms; + *cntp = cnt; + +error: + fclose(f); + hashmap__free(map); + if (err) { + for (i = 0; i < cnt; i++) + free(syms[cnt]); + free(syms); + } + return err; +} + +static void test_bench_attach(void) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts); + struct kprobe_multi_empty *skel = NULL; + long attach_start_ns, attach_end_ns; + long detach_start_ns, detach_end_ns; + double attach_delta, detach_delta; + struct bpf_link *link = NULL; + char **syms = NULL; + size_t cnt, i; + + if (!ASSERT_OK(get_syms(&syms, &cnt), "get_syms")) + return; + + skel = kprobe_multi_empty__open_and_load(); + if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load")) + goto cleanup; + + opts.syms = (const char **) syms; + opts.cnt = cnt; + + attach_start_ns = get_time_ns(); + link = bpf_program__attach_kprobe_multi_opts(skel->progs.test_kprobe_empty, + NULL, &opts); + attach_end_ns = get_time_ns(); + + if (!ASSERT_OK_PTR(link, "bpf_program__attach_kprobe_multi_opts")) + goto cleanup; + + detach_start_ns = get_time_ns(); + bpf_link__destroy(link); + detach_end_ns = get_time_ns(); + + attach_delta = (attach_end_ns - attach_start_ns) / 1000000000.0; + detach_delta = (detach_end_ns - detach_start_ns) / 1000000000.0; + + printf("%s: found %lu functions\n", __func__, cnt); + printf("%s: attached in %7.3lfs\n", __func__, attach_delta); + printf("%s: detached in %7.3lfs\n", __func__, detach_delta); + +cleanup: + kprobe_multi_empty__destroy(skel); + if (syms) { + for (i = 0; i < cnt; i++) + free(syms[i]); + free(syms); + } +} + void test_kprobe_multi_test(void) { if (!ASSERT_OK(load_kallsyms(), "load_kallsyms")) @@ -320,4 +463,6 @@ void test_kprobe_multi_test(void) test_attach_api_syms(); if (test__start_subtest("attach_api_fails")) test_attach_api_fails(); + if (test__start_subtest("bench_attach")) + test_bench_attach(); } |