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

Tingwei Zhang
2020-08-13T01:48:11Z

On Thu, Aug 13, 2020 at 12:49:25AM +0800, Mathieu Poirier wrote:
> On Tue, Aug 11, 2020 at 11:57:20AM +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.
>
> As the get_maintainer script points out, you are missing the maintainer of
> the
> system trace subsystem.
>
Sorry for missing that. I resent the patch and add Alexander.

> >
> > 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)
> >
> > 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(-)
> >
> > --
> > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora
> Forum,
> > a Linux Foundation Collaborative Project
> >