From: Zhaolei If we use trace_event alone(without function trace, .etc), it can't output enough task command information. Before patch: # echo 1 > debugfs/tracing/events/sched/sched_switch/enable # cat debugfs/tracing/trace # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | <...>-2289 [000] 526276.724790: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] <...>-2287 [000] 526276.725231: sched_switch: task sshd:2287 [120] ==> bash:2289 [120] <...>-2289 [000] 526276.725452: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] <...>-2287 [000] 526276.727181: sched_switch: task sshd:2287 [120] ==> swapper:0 [140] -0 [000] 526277.032734: sched_switch: task swapper:0 [140] ==> events/0:5 [115] <...>-5 [000] 526277.032782: sched_switch: task events/0:5 [115] ==> swapper:0 [140] ... After patch: # tracer: nop # # TASK-PID CPU# TIMESTAMP FUNCTION # | | | | | bash-2269 [000] 527347.989229: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] sshd-2267 [000] 527347.990960: sched_switch: task sshd:2267 [120] ==> bash:2269 [120] bash-2269 [000] 527347.991143: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] sshd-2267 [000] 527347.992959: sched_switch: task sshd:2267 [120] ==> swapper:0 [140] -0 [000] 527348.531989: sched_switch: task swapper:0 [140] ==> events/0:5 [115] events/0-5 [000] 527348.532115: sched_switch: task events/0:5 [115] ==> swapper:0 [140] ... Signed-off-by: Zhao Lei LKML-Reference: <4A14FDFE.2080402@cn.fujitsu.com> Signed-off-by: Steven Rostedt --- kernel/trace/trace_events.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 9e91c4a..9b246eb 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -85,6 +85,7 @@ static void ftrace_clear_events(void) if (call->enabled) { call->enabled = 0; + tracing_stop_cmdline_record(); call->unregfunc(); } } @@ -99,12 +100,14 @@ static void ftrace_event_enable_disable(struct ftrace_event_call *call, case 0: if (call->enabled) { call->enabled = 0; + tracing_stop_cmdline_record(); call->unregfunc(); } break; case 1: if (!call->enabled) { call->enabled = 1; + tracing_start_cmdline_record(); call->regfunc(); } break; @@ -1058,6 +1061,7 @@ static void trace_module_remove_events(struct module *mod) found = true; if (call->enabled) { call->enabled = 0; + tracing_stop_cmdline_record(); call->unregfunc(); } if (call->event) @@ -1262,11 +1266,13 @@ static __init void event_trace_self_tests(void) } call->enabled = 1; + tracing_start_cmdline_record(); call->regfunc(); event_test_stuff(); call->unregfunc(); + tracing_stop_cmdline_record(); call->enabled = 0; pr_cont("OK\n"); -- 1.6.2.4 -- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/