perf probe: Show accessible global variables

Add --externs for allowing --vars to show accessible global (externally
defined) variables from a given probe point too.

This will give you a hint which globals can be accessible from the probe point.

Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20101021101335.3542.31003.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/tools/perf/builtin-probe.c b/tools/perf/builtin-probe.c
index c777bec28466..bdf60cfdf70f 100644
--- a/tools/perf/builtin-probe.c
+++ b/tools/perf/builtin-probe.c
@@ -51,6 +51,7 @@ static struct {
         bool force_add;
         bool show_lines;
         bool show_vars;
+        bool show_ext_vars;
         bool mod_events;
         int nevents;
         struct perf_probe_event events[MAX_PROBES];
@@ -162,7 +163,7 @@ static const char * const probe_usage[] = {
         "perf probe --list",
 #ifdef DWARF_SUPPORT
         "perf probe --line 'LINEDESC'",
-        "perf probe --vars 'PROBEPOINT'",
+        "perf probe [--externs] --vars 'PROBEPOINT'",
 #endif
         NULL
 };
@@ -207,6 +208,8 @@ static const struct option options[] = {
         OPT_CALLBACK('V', "vars", NULL,
                      "FUNC[@SRC][+OFF|%return|:RL|;PT]|SRC:AL|SRC;PT",
                      "Show accessible variables on PROBEDEF", opt_show_vars),
+        OPT_BOOLEAN('\0', "externs", &params.show_ext_vars,
+                    "Show external variables too (with --vars only)"),
         OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
                    "file", "vmlinux pathname"),
         OPT_STRING('s', "source", &symbol_conf.source_prefix,
@@ -287,7 +290,8 @@ int cmd_probe(int argc, const char **argv, const char *prefix __used)
                         usage_with_options(probe_usage, options);
                 }
                 ret = show_available_vars(params.events, params.nevents,
-                                          params.max_probe_points);
+                                          params.max_probe_points,
+                                          params.show_ext_vars);
                 if (ret < 0)
                         pr_err("  Error: Failed to show vars. (%d)\n", ret);
                 return ret;