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| author | Steven Rostedt (Red Hat) <rostedt@goodmis.org> | 2014-01-14 13:06:29 +0100 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2014-04-21 19:59:28 +0200 |
| commit | 65daaca7c6dac4db0ef64f2baac0e448cf5d847f (patch) | |
| tree | 062503f1c7129c76cd79590f925ec763ba076171 /kernel/trace/trace_sched_wakeup.c | |
| parent | tracing: Move ftrace_max_lock into trace_array (diff) | |
| download | linux-65daaca7c6dac4db0ef64f2baac0e448cf5d847f.tar.xz linux-65daaca7c6dac4db0ef64f2baac0e448cf5d847f.zip | |
tracing: Allow wakeup tracers to be used by instances
The wakeup and wakeup_rt tracers can now be used by instances.
But they may only be used by one instance at a time (including the
top level directory). This allows multiple tracers to run while
the wakeup tracer is running simultaneously.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/trace_sched_wakeup.c')
| -rw-r--r-- | kernel/trace/trace_sched_wakeup.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 41e0b8aa78ed..1573c03640d2 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -601,6 +601,8 @@ static void stop_wakeup_tracer(struct trace_array *tr) unregister_trace_sched_migrate_task(probe_wakeup_migrate_task, NULL); } +static bool wakeup_busy; + static int __wakeup_tracer_init(struct trace_array *tr) { save_flags = trace_flags; @@ -613,11 +615,16 @@ static int __wakeup_tracer_init(struct trace_array *tr) wakeup_trace = tr; ftrace_init_array_ops(tr, wakeup_tracer_call); start_wakeup_tracer(tr); + + wakeup_busy = true; return 0; } static int wakeup_tracer_init(struct trace_array *tr) { + if (wakeup_busy) + return -EBUSY; + wakeup_dl = 0; wakeup_rt = 0; return __wakeup_tracer_init(tr); @@ -625,6 +632,9 @@ static int wakeup_tracer_init(struct trace_array *tr) static int wakeup_rt_tracer_init(struct trace_array *tr) { + if (wakeup_busy) + return -EBUSY; + wakeup_dl = 0; wakeup_rt = 1; return __wakeup_tracer_init(tr); @@ -632,6 +642,9 @@ static int wakeup_rt_tracer_init(struct trace_array *tr) static int wakeup_dl_tracer_init(struct trace_array *tr) { + if (wakeup_busy) + return -EBUSY; + wakeup_dl = 1; wakeup_rt = 0; return __wakeup_tracer_init(tr); @@ -649,6 +662,7 @@ static void wakeup_tracer_reset(struct trace_array *tr) set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); ftrace_reset_array_ops(tr); + wakeup_busy = false; } static void wakeup_tracer_start(struct trace_array *tr) @@ -680,6 +694,7 @@ static struct tracer wakeup_tracer __read_mostly = #endif .open = wakeup_trace_open, .close = wakeup_trace_close, + .allow_instances = true, .use_max_tr = true, }; @@ -702,6 +717,7 @@ static struct tracer wakeup_rt_tracer __read_mostly = #endif .open = wakeup_trace_open, .close = wakeup_trace_close, + .allow_instances = true, .use_max_tr = true, }; |