perf buildid-list: Add option to show the running kernel build id
[root@emilia ~]# perf buildid-list -k
07b0c016a2b30004e86132d0239945b1e88f5d75
Useful when diagnosing build id problems in debuginfo packages, etc.
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-po1bl7acn6e1hhne90opmvtl@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/Documentation/perf-buildid-list.txt b/tools/perf/Documentation/perf-buildid-list.txt
index 5eaac6f..770a7f3 100644
--- a/tools/perf/Documentation/perf-buildid-list.txt
+++ b/tools/perf/Documentation/perf-buildid-list.txt
@@ -16,6 +16,8 @@
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.
+
OPTIONS
-------
-H::
@@ -27,6 +29,9 @@
-f::
--force::
Don't do ownership validation.
+-k::
+--kernel::
+ Show running kernel build id.
-v::
--verbose::
Be more verbose.
diff --git a/tools/perf/builtin-buildid-list.c b/tools/perf/builtin-buildid-list.c
index 5af32ae..4102ead 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 or in the running
+ * kernel.
*
* Copyright (C) 2009, Red Hat Inc.
* Copyright (C) 2009, Arnaldo Carvalho de Melo <acme@redhat.com>
@@ -17,6 +18,7 @@
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 +31,13 @@
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 +55,30 @@
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 __cmd_buildid_list(void)
+{
+
+ if (show_kernel)
+ return sysfs__fprintf_build_id(stdout);
+
+ 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);