From e9d25fe6eaa2c720bb3ea661b660e58d54fa38bf Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 4 Mar 2009 22:15:30 -0500 Subject: tracing: have latency tracers set the latency format The latency tracers (irqsoff, preemptoff, preemptirqsoff, and wakeup) are pretty useless with the default output format. This patch makes them automatically enable the latency format when they are selected. They also record the state of the latency option, and if it was not enabled when selected, they disable it on reset. Signed-off-by: Steven Rostedt --- kernel/trace/trace_irqsoff.c | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'kernel/trace/trace_irqsoff.c') diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 9e5ebd844158..b923d13e2fad 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -32,6 +32,8 @@ enum { static int trace_type __read_mostly; +static int save_lat_flag; + #ifdef CONFIG_PREEMPT_TRACER static inline int preempt_trace(void) @@ -370,6 +372,9 @@ static void stop_irqsoff_tracer(struct trace_array *tr) static void __irqsoff_tracer_init(struct trace_array *tr) { + save_lat_flag = trace_flags & TRACE_ITER_LATENCY_FMT; + trace_flags |= TRACE_ITER_LATENCY_FMT; + tracing_max_latency = 0; irqsoff_trace = tr; /* make sure that the tracer is visible */ @@ -380,6 +385,9 @@ static void __irqsoff_tracer_init(struct trace_array *tr) static void irqsoff_tracer_reset(struct trace_array *tr) { stop_irqsoff_tracer(tr); + + if (!save_lat_flag) + trace_flags &= ~TRACE_ITER_LATENCY_FMT; } static void irqsoff_tracer_start(struct trace_array *tr) -- cgit v1.2.2