Re: [PATCH 2/2] tracing/fastboot: Use the ring-buffer timestampfor initcall entries

From: Ingo Molnar
Date: Wed Nov 12 2008 - 04:26:11 EST



* Frederic Weisbecker <fweisbec@xxxxxxxxx> wrote:

> Impact: Split the boot tracer entries in two parts: call and return
>
> Now that we are using the sched tracer from the boot tracer, we want
> to use the same timestamp than the ring-buffer to have consistent
> time captures between sched events and initcall events. So we get
> rid of the old time capture by the boot tracer and split the
> initcall events in two parts: call and return. This way we have the
> ring buffer timestamp of both.
>
> There is an example of a trace in attachment.
>
> Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx>
> ---
> include/trace/boot.h | 31 ++++++++---
> init/main.c | 32 ++++++------
> kernel/trace/trace.h | 17 ++++--
> kernel/trace/trace_boot.c | 123 ++++++++++++++++++++++++++++++++++-----------
> 4 files changed, 144 insertions(+), 59 deletions(-)

applied to tip/tracing/fastboot, thanks Frederic!

one small detail, do we need these messages in the boot tracer:

##### CPU 1 buffer started ####

they are helpful for latency traces but might be confusing for boot
traces. (they lose their attraction after having seen a dozen of them)

Ingo
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