From 7a6f205d623afaf05aee387aa6bc57fa43421061 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 29 Aug 2011 08:33:17 -0300 Subject: [PATCH] perf buildid-list: Support showing the build id in an ELF file Try first reading the build id, validating that it is an ELF file, etc. Cheap as libelf will bail out as soon as the magic number check fails. Useful when investigating debuginfo packaging problems like this one: [root@emilia ~]# perf buildid-list -i /usr/lib/debug/lib/modules/`uname -r`/vmlinux 77bb4ea591a602d455ace759a377c9adfff1aba3 [root@emilia ~]# perf buildid-list -k 07b0c016a2b30004e86132d0239945b1e88f5d75 [root@emilia ~]# Cc: David Ahern Cc: Frederic Weisbecker Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-4elot9oxwa0rr0d90dshca3a@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/Documentation/perf-buildid-list.txt | 3 ++- tools/perf/builtin-buildid-list.c | 27 +++++++++++++++++++++++--- 2 files changed, 26 insertions(+), 4 deletions(-) diff --git a/tools/perf/Documentation/perf-buildid-list.txt b/tools/perf/Documentation/perf-buildid-list.txt index 770a7f3..cc22325 100644 --- a/tools/perf/Documentation/perf-buildid-list.txt +++ b/tools/perf/Documentation/perf-buildid-list.txt @@ -16,7 +16,8 @@ This command displays the buildids found in a perf.data file, so that other tools can be used to fetch packages with matching symbol tables for use by perf report. -It can also be used to show the build id of the running kernel. +It can also be used to show the build id of the running kernel or in an ELF +file using -i/--input. OPTIONS ------- diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c index 4102ead..cb690a6 100644 --- a/tools/perf/builtin-buildid-list.c +++ b/tools/perf/builtin-buildid-list.c @@ -1,8 +1,8 @@ /* * builtin-buildid-list.c * - * Builtin buildid-list command: list buildids in perf.data or in the running - * kernel. + * Builtin buildid-list command: list buildids in perf.data, in the running + * kernel and in ELF files. * * Copyright (C) 2009, Red Hat Inc. * Copyright (C) 2009, Arnaldo Carvalho de Melo @@ -16,6 +16,8 @@ #include "util/session.h" #include "util/symbol.h" +#include + static char const *input_name = "perf.data"; static bool force; static bool show_kernel; @@ -70,12 +72,31 @@ static int sysfs__fprintf_build_id(FILE *fp) return 0; } -static int __cmd_buildid_list(void) +static int filename__fprintf_build_id(const char *name, FILE *fp) { + u8 build_id[BUILD_ID_SIZE]; + char sbuild_id[BUILD_ID_SIZE * 2 + 1]; + if (filename__read_build_id(name, build_id, + sizeof(build_id)) != sizeof(build_id)) + return 0; + + build_id__sprintf(build_id, sizeof(build_id), sbuild_id); + return fprintf(fp, "%s\n", sbuild_id); +} + +static int __cmd_buildid_list(void) +{ if (show_kernel) return sysfs__fprintf_build_id(stdout); + elf_version(EV_CURRENT); + /* + * See if this is an ELF file first: + */ + if (filename__fprintf_build_id(input_name, stdout)) + return 0; + return perf_session__list_build_ids(); } -- 2.7.4