There is a resrtiction of "trace-cmd start" which does not allow it to
run a command, specified by "-F" option or at the end of the command
line. However, there are use cases where this is useful.
The resrtiction is removed, it allows "trace-cmd start" to run commands
just like "trace-cmd record".
Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@xxxxxxxxx>
---
Documentation/trace-cmd-start.1.txt | 2 +-
tracecmd/trace-record.c | 28 ++++++++++++++++++++--------
tracecmd/trace-usage.c | 2 +-
3 files changed, 22 insertions(+), 10 deletions(-)
diff --git a/Documentation/trace-cmd-start.1.txt b/Documentation/trace-cmd-start.1.txt
index 2b027b01..63d2034c 100644
--- a/Documentation/trace-cmd-start.1.txt
+++ b/Documentation/trace-cmd-start.1.txt
@@ -21,7 +21,7 @@ system or can be extracted with trace-cmd-extract(1).
OPTIONS
-------
The options are the same as 'trace-cmd-record(1)', except that it does not
-take options specific to recording (*-s*, *-o*, *-F*, *-N*, and *-t*).
+take options specific to recording (*-s*, *-o*, *-N*, and *-t*).
SEE ALSO
--------
diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 3242368e..f345c6d6 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -1598,7 +1598,8 @@ static void run_cmd(enum trace_type type, const char *user, int argc, char **arg
/* child */
update_task_filter();
tracecmd_enable_tracing();
- enable_ptrace();
+ if (type != TRACE_TYPE_START)
+ enable_ptrace();
/*
* If we are using stderr for stdout, switch
* it back to the saved stdout for the code we run.
@@ -1619,6 +1620,8 @@ static void run_cmd(enum trace_type type, const char *user, int argc, char **arg
die("Failed to exec %s", argv[0]);
}
}
+ if (type & TRACE_TYPE_START)
+ exit(0);
if (do_ptrace) {
ptrace_attach(NULL, pid);
ptrace_wait(type);
@@ -5782,6 +5785,14 @@ static void add_arg(struct buffer_instance *instance,
/* Not found? */
}
+static inline void cmd_check_die(struct common_record_context *ctx,
+ enum trace_cmd id, char *cmd, char *param)
+{
+ if (ctx->curr_cmd == id)
+ die("%s has no effect with the command %s\n"
+ "Did you mean 'record'?", param, cmd);
+}
+
static void parse_record_options(int argc,
char **argv,
enum trace_cmd curr_cmd,
@@ -6114,6 +6125,7 @@ static void parse_record_options(int argc,
die("Failed to allocate user name");
break;
case OPT_procmap:
+ cmd_check_die(ctx, CMD_start, *(argv+1), "--proc-map");
ctx->instance->get_procmap = 1;
break;
case OPT_date:
@@ -6221,9 +6233,6 @@ static void parse_record_options(int argc,
die(" -c can only be used with -F (or -P with event-fork support)");
if ((argc - optind) >= 2) {
- if (IS_START(ctx))
- die("Command start does not take any commands\n"
- "Did you mean 'record'?");
if (IS_EXTRACT(ctx))
die("Command extract does not take any commands\n"
"Did you mean 'record'?");
@@ -6244,6 +6253,9 @@ static void parse_record_options(int argc,
}
}
+ if (do_ptrace && IS_START(ctx))
+ die("ptrace not supported with command start");
+
for_all_instances(instance) {
if (instance->get_procmap && !instance->nr_filter_pids) {
warning("--proc-map is ignored for instance %s, "
@@ -6410,10 +6422,6 @@ static void record_trace(int argc, char **argv,
signal(SIGINT, finish);
if (!latency)
start_threads(type, ctx);
- } else {
- update_task_filter();
- tracecmd_enable_tracing();
- exit(0);
}
if (ctx->run_command) {
@@ -6428,6 +6436,10 @@ static void record_trace(int argc, char **argv,
update_task_filter();
tracecmd_enable_tracing();
+
+ if (type & TRACE_TYPE_START)
+ exit(0);
+
/* We don't ptrace ourself */
if (do_ptrace) {
for_all_instances(instance) {
diff --git a/tracecmd/trace-usage.c b/tracecmd/trace-usage.c
index d43ca490..58bca9e4 100644
--- a/tracecmd/trace-usage.c
+++ b/tracecmd/trace-usage.c
@@ -69,7 +69,7 @@ static struct usage_help usage_help[] = {
"start",
"start tracing without recording into a file",
" %s start [-e event][-p plugin][-d][-O option ][-P pid]\n"
- " Uses same options as record, but does not run a command.\n"
+ " Uses same options as record.\n"
" It only enables the tracing and exits\n"
},
{
--
2.26.2
|