diff options
| -rw-r--r-- | kernel/trace/trace.c | 7 | ||||
| -rw-r--r-- | kernel/trace/trace.h | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_functions.c | 2 | ||||
| -rw-r--r-- | kernel/trace/trace_sched_switch.c | 7 |
4 files changed, 15 insertions, 3 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index a102b11eacf..1281969103b 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -620,7 +620,12 @@ static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; static int cmdline_idx; static DEFINE_SPINLOCK(trace_cmdline_lock); -atomic_t trace_record_cmdline_disabled; + +/* trace in all context switches */ +atomic_t trace_record_cmdline_enabled __read_mostly; + +/* temporary disable recording */ +atomic_t trace_record_cmdline_disabled __read_mostly; static void trace_init_cmdlines(void) { diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 21c29ee13e5..8991c5efcc7 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -216,6 +216,8 @@ extern unsigned long nsecs_to_usecs(unsigned long nsecs); extern unsigned long tracing_max_latency; extern unsigned long tracing_thresh; +extern atomic_t trace_record_cmdline_enabled; + void update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu); void update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu); diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 4165d34bd28..0a084656d7c 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -29,12 +29,14 @@ static void function_reset(struct trace_array *tr) static void start_function_trace(struct trace_array *tr) { function_reset(tr); + atomic_inc(&trace_record_cmdline_enabled); tracing_start_function_trace(); } static void stop_function_trace(struct trace_array *tr) { tracing_stop_function_trace(); + atomic_dec(&trace_record_cmdline_enabled); } static void function_trace_init(struct trace_array *tr) diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index 5671db0e182..a3376478fc2 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -29,8 +29,6 @@ ctx_switch_func(void *__rq, struct task_struct *prev, struct task_struct *next) if (!tracer_enabled) return; - tracing_record_cmdline(prev); - local_irq_save(flags); cpu = raw_smp_processor_id(); data = tr->data[cpu]; @@ -73,6 +71,9 @@ void ftrace_ctx_switch(void *__rq, struct task_struct *prev, struct task_struct *next) { + if (unlikely(atomic_read(&trace_record_cmdline_enabled))) + tracing_record_cmdline(prev); + /* * If tracer_switch_func only points to the local * switch func, it still needs the ptr passed to it. @@ -134,11 +135,13 @@ static void sched_switch_reset(struct trace_array *tr) static void start_sched_trace(struct trace_array *tr) { sched_switch_reset(tr); + atomic_inc(&trace_record_cmdline_enabled); tracer_enabled = 1; } static void stop_sched_trace(struct trace_array *tr) { + atomic_dec(&trace_record_cmdline_enabled); tracer_enabled = 0; } |