1 files changed, 50 insertions, 2 deletions

diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
index 5af32ae9031e..cb690a65bf02 100644
--- a/tools/perf/builtin-buildid-list.c
+++ b/tools/perf/builtin-buildid-list.c
@@ -1,7 +1,8 @@
 /*
  * builtin-buildid-list.c
  *
- * Builtin buildid-list command: list buildids in perf.data
+ * 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 <acme@redhat.com>
@@ -15,8 +16,11 @@
 #include "util/session.h"
 #include "util/symbol.h"
 
+#include <libelf.h>
+
 static char const *input_name = "perf.data";
 static bool force;
+static bool show_kernel;
 static bool with_hits;
 
 static const char * const buildid_list_usage[] = {
@@ -29,12 +33,13 @@ static const struct option options[] = {
         OPT_STRING('i', "input", &input_name, "file",
                     "input file name"),
         OPT_BOOLEAN('f', "force", &force, "don't complain, do it"),
+        OPT_BOOLEAN('k', "kernel", &show_kernel, "Show current kernel build id"),
         OPT_INCR('v', "verbose", &verbose,
                     "be more verbose"),
         OPT_END()
 };
 
-static int __cmd_buildid_list(void)
+static int perf_session__list_build_ids(void)
 {
         struct perf_session *session;
 
@@ -52,6 +57,49 @@ static int __cmd_buildid_list(void)
         return 0;
 }
 
+static int sysfs__fprintf_build_id(FILE *fp)
+{
+        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)
+                return -1;
+
+        build_id__sprintf(kallsyms_build_id, sizeof(kallsyms_build_id),
+                          sbuild_id);
+        fprintf(fp, "%s\n", sbuild_id);
+        return 0;
+}
+
+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();
+}
+
 int cmd_buildid_list(int argc, const char **argv, const char *prefix __used)
 {
         argc = parse_options(argc, argv, options, buildid_list_usage, 0);