tracing/sysprof: add missing tracing_{start,stop}_record_cmdline()

Add the missing pair tracing_{start,stop}_record_cmdline() to record well
the cmdline associated with pid.

Changes in v2:

- fix a build error, the sched_switch tracer is needed to record the
  cmdline.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 4 insertions, 0 deletions

diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 3a331289457a..6ff928acd453 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -134,6 +134,7 @@ config SYSPROF_TRACER
         bool "Sysprof Tracer"
         depends on X86
         select TRACING
+        select CONTEXT_SWITCH_TRACER
         help
           This tracer provides the trace needed by the 'Sysprof' userspace
           tool.
diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c
index 84ca9d81e74d..9902c15997ad 100644
--- a/kernel/trace/trace_sysprof.c
+++ b/kernel/trace/trace_sysprof.c
@@ -238,6 +238,8 @@ static int stack_trace_init(struct trace_array *tr)
 {
         sysprof_trace = tr;
 
+        tracing_start_cmdline_record();
+
         mutex_lock(&sample_timer_lock);
         start_stack_timers();
         tracer_enabled = 1;
@@ -247,6 +249,7 @@ static int stack_trace_init(struct trace_array *tr)
 
 static void stack_trace_reset(struct trace_array *tr)
 {
+        tracing_stop_cmdline_record();
         stop_stack_trace(tr);
 }