Commit 4fdd595e authored by Steven Rostedt (VMware)'s avatar Steven Rostedt (VMware)
Browse files

tracing: Do not stop recording comms if the trace file is being read 



A while ago, when the "trace" file was opened, tracing was stopped, and
code was added to stop recording the comms to saved_cmdlines, for mapping
of the pids to the task name.

Code has been added that only records the comm if a trace event occurred,
and there's no reason to not trace it if the trace file is opened.

Cc: stable@vger.kernel.org
Fixes: 7ffbd48d ("tracing: Cache comms only after an event occurred")
Signed-off-by: default avatarSteven Rostedt (VMware) <rostedt@goodmis.org>
parent 85550c83

kernel/trace/trace.c

+0 −9
Original line number Diff line number Diff line
@@ -2198,9 +2198,6 @@ struct saved_cmdlines_buffer { 
};

static struct saved_cmdlines_buffer *savedcmd;



/* temporary disable recording */

static atomic_t trace_record_taskinfo_disabled __read_mostly;



static inline char *get_saved_cmdlines(int idx)

{

	return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN];
@@ -3996,9 +3993,6 @@ static void *s_start(struct seq_file *m, loff_t *pos) 
		return ERR_PTR(-EBUSY);

#endif



	if (!iter->snapshot)

		atomic_inc(&trace_record_taskinfo_disabled);



	if (*pos != iter->pos) {

		iter->ent = NULL;

		iter->cpu = 0;
@@ -4041,9 +4035,6 @@ static void s_stop(struct seq_file *m, void *p) 
		return;

#endif



	if (!iter->snapshot)

		atomic_dec(&trace_record_taskinfo_disabled);



	trace_access_unlock(iter->cpu_file);

	trace_event_read_unlock();

}