1 // SPDX-License-Identifier: GPL-2.0 2 #include <errno.h> 3 #include <limits.h> 4 #include <stdio.h> 5 #include <stdlib.h> 6 #include <unistd.h> 7 #include <sys/epoll.h> 8 #include <util/symbol.h> 9 #include <linux/filter.h> 10 #include "tests.h" 11 #include "debug.h" 12 #include "probe-file.h" 13 #include "build-id.h" 14 #include "util.h" 15 16 /* To test SDT event, we need libelf support to scan elf binary */ 17 #if defined(HAVE_SDT_EVENT) && defined(HAVE_LIBELF_SUPPORT) 18 19 #include <sys/sdt.h> 20 21 static int target_function(void) 22 { 23 DTRACE_PROBE(perf, test_target); 24 return TEST_OK; 25 } 26 27 /* Copied from builtin-buildid-cache.c */ 28 static int build_id_cache__add_file(const char *filename) 29 { 30 char sbuild_id[SBUILD_ID_SIZE]; 31 u8 build_id[BUILD_ID_SIZE]; 32 int err; 33 34 err = filename__read_build_id(filename, &build_id, sizeof(build_id)); 35 if (err < 0) { 36 pr_debug("Failed to read build id of %s\n", filename); 37 return err; 38 } 39 40 build_id__sprintf(build_id, sizeof(build_id), sbuild_id); 41 err = build_id_cache__add_s(sbuild_id, filename, NULL, false, false); 42 if (err < 0) 43 pr_debug("Failed to add build id cache of %s\n", filename); 44 return err; 45 } 46 47 static char *get_self_path(void) 48 { 49 char *buf = calloc(PATH_MAX, sizeof(char)); 50 51 if (buf && readlink("/proc/self/exe", buf, PATH_MAX - 1) < 0) { 52 pr_debug("Failed to get correct path of perf\n"); 53 free(buf); 54 return NULL; 55 } 56 return buf; 57 } 58 59 static int search_cached_probe(const char *target, 60 const char *group, const char *event) 61 { 62 struct probe_cache *cache = probe_cache__new(target, NULL); 63 int ret = 0; 64 65 if (!cache) { 66 pr_debug("Failed to open probe cache of %s\n", target); 67 return -EINVAL; 68 } 69 70 if (!probe_cache__find_by_name(cache, group, event)) { 71 pr_debug("Failed to find %s:%s in the cache\n", group, event); 72 ret = -ENOENT; 73 } 74 probe_cache__delete(cache); 75 76 return ret; 77 } 78 79 int test__sdt_event(struct test *test __maybe_unused, int subtests __maybe_unused) 80 { 81 int ret = TEST_FAIL; 82 char __tempdir[] = "./test-buildid-XXXXXX"; 83 char *tempdir = NULL, *myself = get_self_path(); 84 85 if (myself == NULL || mkdtemp(__tempdir) == NULL) { 86 pr_debug("Failed to make a tempdir for build-id cache\n"); 87 goto error; 88 } 89 /* Note that buildid_dir must be an absolute path */ 90 tempdir = realpath(__tempdir, NULL); 91 if (tempdir == NULL) 92 goto error_rmdir; 93 94 /* At first, scan itself */ 95 set_buildid_dir(tempdir); 96 if (build_id_cache__add_file(myself) < 0) 97 goto error_rmdir; 98 99 /* Open a cache and make sure the SDT is stored */ 100 if (search_cached_probe(myself, "sdt_perf", "test_target") < 0) 101 goto error_rmdir; 102 103 /* TBD: probing on the SDT event and collect logs */ 104 105 /* Call the target and get an event */ 106 ret = target_function(); 107 108 error_rmdir: 109 /* Cleanup temporary buildid dir */ 110 rm_rf(__tempdir); 111 error: 112 free(tempdir); 113 free(myself); 114 return ret; 115 } 116 #else 117 int test__sdt_event(struct test *test __maybe_unused, int subtests __maybe_unused) 118 { 119 pr_debug("Skip SDT event test because SDT support is not compiled\n"); 120 return TEST_SKIP; 121 } 122 #endif 123