Re: [PATCH] Documentation/ftrace: Correct wording on trace_options sharing

From: Steven Rostedt
Date: Wed Feb 21 2024 - 10:45:44 EST


On Wed, 21 Feb 2024 01:59:53 +0000
Dmitry Safonov <dima@xxxxxxxxxx> wrote:

> On 2/20/24 21:00, Dmitry Safonov wrote:
> [..]
> > diff --git a/Documentation/trace/ftrace.rst b/Documentation/trace/ftrace.rst
> > index 7e7b8ec17934..c79a6bcef3c9 100644
> > --- a/Documentation/trace/ftrace.rst
> > +++ b/Documentation/trace/ftrace.rst
> > @@ -3603,9 +3603,9 @@ The files in the new directory work just like the files with the
> > same name in the tracing directory except the buffer that is used
> > is a separate and new buffer. The files affect that buffer but do not
> > affect the main buffer with the exception of trace_options. Currently,
> > -the trace_options affect all instances and the top level buffer
> > -the same, but this may change in future releases. That is, options
> > -may become specific to the instance they reside in.
> > +most of the options are specific to the instance they reside in, but
> > +trace_printk, printk-msg-only and record-cmd are affecting all instances
> > +and the top level buffer, but this may change in future releases.
>
> Actually, it seems that at least on -next these 3 are not shared as
> well? (if my tests aren't misbehaving)
>
> So, just remove the part about trace_options exception?
>

In reality, if we want to be specific. It should state that all options
listed in the instance options directory are unique to the instance. If an
option only exists in the top directory, then it is global or for a tracer
that can only be used in the top directory.

-- Steve