Commit-ID: 0544d4225c52ca31ab2a55b22ddce1392d8f45a4 Gitweb: http://git.kernel.org/tip/0544d4225c52ca31ab2a55b22ddce1392d8f45a4 Author: Adrian Hunter <adrian.hun...@intel.com> AuthorDate: Mon, 14 Oct 2013 13:43:43 +0300 Committer: Arnaldo Carvalho de Melo <a...@redhat.com> CommitDate: Mon, 14 Oct 2013 10:29:25 -0300
perf symbols: Add ability to find kcore in build-id cache When no vmlinux is found, tools will use kallsyms and, if possible, kcore. Add the ability to find kcore in the build-id cache. Signed-off-by: Adrian Hunter <adrian.hun...@intel.com> Cc: David Ahern <dsah...@gmail.com> Cc: Frederic Weisbecker <fweis...@gmail.com> Cc: Jiri Olsa <jo...@redhat.com> Cc: Mike Galbraith <efa...@gmx.de> Cc: Namhyung Kim <namhy...@gmail.com> Cc: Paul Mackerras <pau...@samba.org> Cc: Peter Zijlstra <a.p.zijls...@chello.nl> Cc: Stephane Eranian <eran...@google.com> Link: http://lkml.kernel.org/r/1381747424-3557-7-git-send-email-adrian.hun...@intel.com Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> --- tools/perf/util/symbol.c | 147 +++++++++++++++++++++++++++++++++-------------- 1 file changed, 103 insertions(+), 44 deletions(-) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index b2f60dd..76a9e93 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1401,6 +1401,105 @@ out: return err; } +static int find_matching_kcore(struct map *map, char *dir, size_t dir_sz) +{ + char kallsyms_filename[PATH_MAX]; + struct dirent *dent; + int ret = -1; + DIR *d; + + d = opendir(dir); + if (!d) + return -1; + + while (1) { + dent = readdir(d); + if (!dent) + break; + if (dent->d_type != DT_DIR) + continue; + scnprintf(kallsyms_filename, sizeof(kallsyms_filename), + "%s/%s/kallsyms", dir, dent->d_name); + if (!validate_kcore_modules(kallsyms_filename, map)) { + strlcpy(dir, kallsyms_filename, dir_sz); + ret = 0; + break; + } + } + + closedir(d); + + return ret; +} + +static char *dso__find_kallsyms(struct dso *dso, struct map *map) +{ + u8 host_build_id[BUILD_ID_SIZE]; + char sbuild_id[BUILD_ID_SIZE * 2 + 1]; + bool is_host = false; + char path[PATH_MAX]; + + if (!dso->has_build_id) { + /* + * Last resort, if we don't have a build-id and couldn't find + * any vmlinux file, try the running kernel kallsyms table. + */ + goto proc_kallsyms; + } + + if (sysfs__read_build_id("/sys/kernel/notes", host_build_id, + sizeof(host_build_id)) == 0) + is_host = dso__build_id_equal(dso, host_build_id); + + build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id); + + /* Use /proc/kallsyms if possible */ + if (is_host) { + DIR *d; + int fd; + + /* If no cached kcore go with /proc/kallsyms */ + scnprintf(path, sizeof(path), "%s/[kernel.kcore]/%s", + buildid_dir, sbuild_id); + d = opendir(path); + if (!d) + goto proc_kallsyms; + closedir(d); + + /* + * Do not check the build-id cache, until we know we cannot use + * /proc/kcore. + */ + fd = open("/proc/kcore", O_RDONLY); + if (fd != -1) { + close(fd); + /* If module maps match go with /proc/kallsyms */ + if (!validate_kcore_modules("/proc/kallsyms", map)) + goto proc_kallsyms; + } + + /* Find kallsyms in build-id cache with kcore */ + if (!find_matching_kcore(map, path, sizeof(path))) + return strdup(path); + + goto proc_kallsyms; + } + + scnprintf(path, sizeof(path), "%s/[kernel.kallsyms]/%s", + buildid_dir, sbuild_id); + + if (access(path, F_OK)) { + pr_err("No kallsyms or vmlinux with build-id %s was found\n", + sbuild_id); + return NULL; + } + + return strdup(path); + +proc_kallsyms: + return strdup("/proc/kallsyms"); +} + static int dso__load_kernel_sym(struct dso *dso, struct map *map, symbol_filter_t filter) { @@ -1449,51 +1548,11 @@ static int dso__load_kernel_sym(struct dso *dso, struct map *map, if (symbol_conf.symfs[0] != 0) return -1; - /* - * Say the kernel DSO was created when processing the build-id header table, - * we have a build-id, so check if it is the same as the running kernel, - * using it if it is. - */ - if (dso->has_build_id) { - u8 kallsyms_build_id[BUILD_ID_SIZE]; - char sbuild_id[BUILD_ID_SIZE * 2 + 1]; - - if (sysfs__read_build_id("/sys/kernel/notes", kallsyms_build_id, - sizeof(kallsyms_build_id)) == 0) { - if (dso__build_id_equal(dso, kallsyms_build_id)) { - kallsyms_filename = "/proc/kallsyms"; - goto do_kallsyms; - } - } - /* - * Now look if we have it on the build-id cache in - * $HOME/.debug/[kernel.kallsyms]. - */ - build_id__sprintf(dso->build_id, sizeof(dso->build_id), - sbuild_id); - - if (asprintf(&kallsyms_allocated_filename, - "%s/.debug/[kernel.kallsyms]/%s", - getenv("HOME"), sbuild_id) == -1) { - pr_err("Not enough memory for kallsyms file lookup\n"); - return -1; - } - - kallsyms_filename = kallsyms_allocated_filename; + kallsyms_allocated_filename = dso__find_kallsyms(dso, map); + if (!kallsyms_allocated_filename) + return -1; - if (access(kallsyms_filename, F_OK)) { - pr_err("No kallsyms or vmlinux with build-id %s " - "was found\n", sbuild_id); - free(kallsyms_allocated_filename); - return -1; - } - } else { - /* - * Last resort, if we don't have a build-id and couldn't find - * any vmlinux file, try the running kernel kallsyms table. - */ - kallsyms_filename = "/proc/kallsyms"; - } + kallsyms_filename = kallsyms_allocated_filename; do_kallsyms: err = dso__load_kallsyms(dso, kallsyms_filename, map, filter); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
