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 | 248 |
1 files changed, 200 insertions, 48 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 05000810e28e..51628455b6f5 100644 --- a/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c +++ b/tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c @@ -336,15 +336,80 @@ static bool symbol_equal(long key1, long key2, void *ctx __maybe_unused) return strcmp((const char *) key1, (const char *) key2) == 0; } +static bool is_invalid_entry(char *buf, bool kernel) +{ + if (kernel && strchr(buf, '[')) + return true; + if (!kernel && !strchr(buf, '[')) + return true; + return false; +} + +static bool skip_entry(char *name) +{ + /* + * 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 + * default_idle and rcu_* functions. + */ + if (!strcmp(name, "arch_cpu_idle")) + return true; + if (!strcmp(name, "default_idle")) + return true; + if (!strncmp(name, "rcu_", 4)) + return true; + if (!strcmp(name, "bpf_dispatcher_xdp_func")) + return true; + if (!strncmp(name, "__ftrace_invalid_address__", + sizeof("__ftrace_invalid_address__") - 1)) + return true; + return false; +} + +/* Do comparision by ignoring '.llvm.<hash>' suffixes. */ +static int compare_name(const char *name1, const char *name2) +{ + const char *res1, *res2; + int len1, len2; + + res1 = strstr(name1, ".llvm."); + res2 = strstr(name2, ".llvm."); + len1 = res1 ? res1 - name1 : strlen(name1); + len2 = res2 ? res2 - name2 : strlen(name2); + + if (len1 == len2) + return strncmp(name1, name2, len1); + if (len1 < len2) + return strncmp(name1, name2, len1) <= 0 ? -1 : 1; + return strncmp(name1, name2, len2) >= 0 ? 1 : -1; +} + +static int load_kallsyms_compare(const void *p1, const void *p2) +{ + return compare_name(((const struct ksym *)p1)->name, ((const struct ksym *)p2)->name); +} + +static int search_kallsyms_compare(const void *p1, const struct ksym *p2) +{ + return compare_name(p1, p2->name); +} + static int get_syms(char ***symsp, size_t *cntp, bool kernel) { - size_t cap = 0, cnt = 0, i; - char *name = NULL, **syms = NULL; + size_t cap = 0, cnt = 0; + char *name = NULL, *ksym_name, **syms = NULL; struct hashmap *map; + struct ksyms *ksyms; + struct ksym *ks; char buf[256]; FILE *f; int err = 0; + ksyms = load_kallsyms_custom_local(load_kallsyms_compare); + if (!ASSERT_OK_PTR(ksyms, "load_kallsyms_custom_local")) + return -EINVAL; + /* * The available_filter_functions contains many duplicates, * but other than that all symbols are usable in kprobe multi @@ -368,33 +433,23 @@ static int get_syms(char ***symsp, size_t *cntp, bool kernel) } while (fgets(buf, sizeof(buf), f)) { - if (kernel && strchr(buf, '[')) - continue; - if (!kernel && !strchr(buf, '[')) + if (is_invalid_entry(buf, kernel)) continue; free(name); 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 - * default_idle and rcu_* functions. - */ - if (!strcmp(name, "arch_cpu_idle")) - continue; - if (!strcmp(name, "default_idle")) - continue; - if (!strncmp(name, "rcu_", 4)) - continue; - if (!strcmp(name, "bpf_dispatcher_xdp_func")) - continue; - if (!strncmp(name, "__ftrace_invalid_address__", - sizeof("__ftrace_invalid_address__") - 1)) + if (skip_entry(name)) continue; - err = hashmap__add(map, name, 0); + ks = search_kallsyms_custom_local(ksyms, name, search_kallsyms_compare); + if (!ks) { + err = -EINVAL; + goto error; + } + + ksym_name = ks->name; + err = hashmap__add(map, ksym_name, 0); if (err == -EEXIST) { err = 0; continue; @@ -407,8 +462,7 @@ static int get_syms(char ***symsp, size_t *cntp, bool kernel) if (err) goto error; - syms[cnt++] = name; - name = NULL; + syms[cnt++] = ksym_name; } *symsp = syms; @@ -418,42 +472,88 @@ error: free(name); fclose(f); hashmap__free(map); - if (err) { - for (i = 0; i < cnt; i++) - free(syms[i]); + if (err) free(syms); + return err; +} + +static int get_addrs(unsigned long **addrsp, size_t *cntp, bool kernel) +{ + unsigned long *addr, *addrs, *tmp_addrs; + int err = 0, max_cnt, inc_cnt; + char *name = NULL; + size_t cnt = 0; + char buf[256]; + FILE *f; + + if (access("/sys/kernel/tracing/trace", F_OK) == 0) + f = fopen("/sys/kernel/tracing/available_filter_functions_addrs", "r"); + else + f = fopen("/sys/kernel/debug/tracing/available_filter_functions_addrs", "r"); + + if (!f) + return -ENOENT; + + /* In my local setup, the number of entries is 50k+ so Let us initially + * allocate space to hold 64k entries. If 64k is not enough, incrementally + * increase 1k each time. + */ + max_cnt = 65536; + inc_cnt = 1024; + addrs = malloc(max_cnt * sizeof(long)); + if (addrs == NULL) { + err = -ENOMEM; + goto error; } + + while (fgets(buf, sizeof(buf), f)) { + if (is_invalid_entry(buf, kernel)) + continue; + + free(name); + if (sscanf(buf, "%p %ms$*[^\n]\n", &addr, &name) != 2) + continue; + if (skip_entry(name)) + continue; + + if (cnt == max_cnt) { + max_cnt += inc_cnt; + tmp_addrs = realloc(addrs, max_cnt); + if (!tmp_addrs) { + err = -ENOMEM; + goto error; + } + addrs = tmp_addrs; + } + + addrs[cnt++] = (unsigned long)addr; + } + + *addrsp = addrs; + *cntp = cnt; + +error: + free(name); + fclose(f); + if (err) + free(addrs); return err; } -static void test_kprobe_multi_bench_attach(bool kernel) +static void do_bench_test(struct kprobe_multi_empty *skel, struct bpf_kprobe_multi_opts *opts) { - 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 = 0, i; - - if (!ASSERT_OK(get_syms(&syms, &cnt, kernel), "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); + NULL, opts); attach_end_ns = get_time_ns(); if (!ASSERT_OK_PTR(link, "bpf_program__attach_kprobe_multi_opts")) - goto cleanup; + return; detach_start_ns = get_time_ns(); bpf_link__destroy(link); @@ -462,17 +562,65 @@ static void test_kprobe_multi_bench_attach(bool kernel) 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: found %lu functions\n", __func__, opts->cnt); printf("%s: attached in %7.3lfs\n", __func__, attach_delta); printf("%s: detached in %7.3lfs\n", __func__, detach_delta); +} + +static void test_kprobe_multi_bench_attach(bool kernel) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts); + struct kprobe_multi_empty *skel = NULL; + char **syms = NULL; + size_t cnt = 0; + + if (!ASSERT_OK(get_syms(&syms, &cnt, kernel), "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; + + do_bench_test(skel, &opts); cleanup: kprobe_multi_empty__destroy(skel); - if (syms) { - for (i = 0; i < cnt; i++) - free(syms[i]); + if (syms) free(syms); +} + +static void test_kprobe_multi_bench_attach_addr(bool kernel) +{ + LIBBPF_OPTS(bpf_kprobe_multi_opts, opts); + struct kprobe_multi_empty *skel = NULL; + unsigned long *addrs = NULL; + size_t cnt = 0; + int err; + + err = get_addrs(&addrs, &cnt, kernel); + if (err == -ENOENT) { + test__skip(); + return; } + + if (!ASSERT_OK(err, "get_addrs")) + return; + + skel = kprobe_multi_empty__open_and_load(); + if (!ASSERT_OK_PTR(skel, "kprobe_multi_empty__open_and_load")) + goto cleanup; + + opts.addrs = addrs; + opts.cnt = cnt; + + do_bench_test(skel, &opts); + +cleanup: + kprobe_multi_empty__destroy(skel); + free(addrs); } static void test_attach_override(void) @@ -515,6 +663,10 @@ void serial_test_kprobe_multi_bench_attach(void) test_kprobe_multi_bench_attach(true); if (test__start_subtest("modules")) test_kprobe_multi_bench_attach(false); + if (test__start_subtest("kernel")) + test_kprobe_multi_bench_attach_addr(true); + if (test__start_subtest("modules")) + test_kprobe_multi_bench_attach_addr(false); } void test_kprobe_multi_test(void) |