trace-cmd: Add --check-events to report

Add a new option --check-events to the report target which makes sure
that the event formats in the trace data file can be parsed correctly on
the machine that trace-cmd is running on. It returns EINVAL(22) for
parsing failures and 0 for success.

Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Link: http://lkml.kernel.org/r/1313091459-12049-4-git-send-email-vnagarnaik@google.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

3 files changed, 29 insertions, 8 deletions

diff --git a/trace-input.c b/trace-input.c
index 723d47f..8c2b858 100644
--- a/trace-input.c
+++ b/trace-input.c
@@ -342,10 +342,12 @@ static int read_ftrace_file(struct tracecmd_input *handle,
                 return -1;
         }
 
-        if (print)
+        if (print) {
                 printf("%.*s\n", (int)size, buf);
-        else
-                pevent_parse_event(pevent, buf, size, "ftrace");
+        } else {
+                if (pevent_parse_event(pevent, buf, size, "ftrace"))
+                        pevent->parsing_failures = 1;
+        }
         free(buf);
 
         return 0;
@@ -367,10 +369,12 @@ static int read_event_file(struct tracecmd_input *handle,
                 return -1;
         }
 
-        if (print)
+        if (print) {
                 printf("%.*s\n", (int)size, buf);
-        else
-                pevent_parse_event(pevent, buf, size, system);
+        } else {
+                if (pevent_parse_event(pevent, buf, size, system))
+                        pevent->parsing_failures = 1;
+        }
         free(buf);
 
         return 0;
diff --git a/trace-read.c b/trace-read.c
index 38e3534..2e45bff 100644
--- a/trace-read.c
+++ b/trace-read.c
@@ -826,6 +826,7 @@ static void process_plugin_option(char *option)
 }
 
 enum {
+        OPT_check_event_parsing = 252,
         OPT_kallsyms    = 253,
         OPT_events      = 254,
         OPT_cpu         = 255,
@@ -848,6 +849,8 @@ void trace_report (int argc, char **argv)
         int test_filters = 0;
         int raw = 0;
         int neg = 0;
+        int ret = 0;
+        int check_event_parsing = 0;
         int c;
 
         list_head_init(&handle_list);
@@ -868,6 +871,8 @@ void trace_report (int argc, char **argv)
                         {"events", no_argument, NULL, OPT_events},
                         {"filter-test", no_argument, NULL, 'T'},
                         {"kallsyms", required_argument, NULL, OPT_kallsyms},
+                        {"check-events", no_argument, NULL,
+                                OPT_check_event_parsing},
                         {"help", no_argument, NULL, '?'},
                         {NULL, 0, NULL, 0}
                 };
@@ -948,6 +953,9 @@ void trace_report (int argc, char **argv)
                 case OPT_kallsyms:
                         functions = optarg;
                         break;
+                case OPT_check_event_parsing:
+                        check_event_parsing = 1;
+                        break;
                 default:
                         usage(argv);
                 }
@@ -1005,8 +1013,16 @@ void trace_report (int argc, char **argv)
                         return;
                 }
 
-                if (tracecmd_read_headers(handle) < 0)
-                        return;
+                ret = tracecmd_read_headers(handle);
+                if (check_event_parsing) {
+                        if (ret || pevent->parsing_failures)
+                                exit(EINVAL);
+                        else
+                                exit(0);
+                } else {
+                        if (ret)
+                                return;
+                }
 
                 if (show_funcs) {
                         pevent_print_funcs(pevent);
diff --git a/trace-usage.c b/trace-usage.c
index 7314657..0e2194e 100644
--- a/trace-usage.c
+++ b/trace-usage.c
@@ -91,6 +91,7 @@ static struct usage_help usage_help[] = {
                 "          -w show wakeup latencies\n"
                 "          -l show latency format (default with latency tracers)\n"
                 "          -O plugin option -O [plugin:]var[=val]\n"
+                "          --check-events return whether all event formats can be parsed\n"
         },
         {
                 "split",