Re: [PATCH v3 0/6] tracing: export event trace and trace_marker

From: Tingwei Zhang
Date: Mon Aug 10 2020 - 23:04:45 EST


Hi Steven,
On Tue, Jul 28, 2020 at 09:33:53AM +0800, Tingwei Zhang wrote:
> Ftrace has ability to export trace packets to other destination.
> Currently, only function trace can be exported. This series extends the
> support to event trace and trace_maker. STM is one possible destination to
> export ftrace. Use separate channel for each CPU to avoid mixing up
> packets
> from different CPUs together.
>
> Change from v2:
> Change flag definition to BIT(). (Steven)
> Add comment in stm_ftrace_write() to clarify it's safe to use
> smp_processor_id() here since preempt is disabled. (Steven)

Thanks for your comments, Steven. I've addressed all your comments in v3.
Do you have more comments on v3? Is there anything I need to do to merge
this series to Linux Kernel?

>
> Change from v1:
> All changes are suggested by Steven Rostedt.
> User separate flag to control function trace, event trace and trace mark.
> Allocate channels according to num_possible_cpu() dynamically.
> Move ftrace_exports routines up so all ftrace can use them.
>
> Tingwei Zhang (6):
> stm class: ftrace: change dependency to TRACING
> tracing: add flag to control different traces
> tracing: add trace_export support for event trace
> tracing: add trace_export support for trace_marker
> stm class: ftrace: enable supported trace export flag
> stm class: ftrace: use different channel accroding to CPU
>
> drivers/hwtracing/stm/Kconfig | 2 +-
> drivers/hwtracing/stm/ftrace.c | 7 +-
> include/linux/trace.h | 7 +
> kernel/trace/trace.c | 270 ++++++++++++++++++---------------
> 4 files changed, 159 insertions(+), 127 deletions(-)
>
> --
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