Re: [PATCH v2 6/6] stm class: ftrace: use different channel accroding to CPU

[Tingwei Zhang]

Hi Steve,
On Tue, Jul 28, 2020 at 03:08:12AM +0800, Steven Rostedt wrote:
> On Sun, 26 Jul 2020 10:59:31 +0800
> Tingwei Zhang <tingwei@xxxxxxxxxxxxxx> wrote:
> 
> > --- a/drivers/hwtracing/stm/ftrace.c
> > +++ b/drivers/hwtracing/stm/ftrace.c
> > @@ -37,8 +37,9 @@ static void notrace
> >  stm_ftrace_write(struct trace_export *export, const void *buf, unsigned
> int len)
> >  {
> >  	struct stm_ftrace *stm = container_of(export, struct stm_ftrace,
> ftrace);
> > +	unsigned int cpu = smp_processor_id();
> 
> Probably should add a comment to the above stating that this is called
> from the tracing system with preemption disabled.
> 

Good point. I'll add that comment in next revision.

Thanks,
Tingwei

> Other than my two comments:
> 
> Reviewed-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
> 
> -- Steve
> 
> 
> >  
> > -	stm_source_write(&stm->data, STM_FTRACE_CHAN, buf, len);
> > +	stm_source_write(&stm->data, STM_FTRACE_CHAN + cpu, buf, len);
> >  }
> >  
> >  static int stm_ftrace_link(struct stm_source_data *data)