Re: [PATCH 3/7] rcu/trace: Add name of the source for gp_seq

[Joel Fernandes]

On Thu, Jun 18, 2020 at 08:01:38PM -0400, Steven Rostedt wrote:
> On Thu, 18 Jun 2020 15:19:01 -0700
> "Paul E. McKenney" <paulmck@xxxxxxxxxx> wrote:
> 
> > For future reference, the TPS() around strings is not optional.  Without
> > it, trace messages from crash dumps are garbled, if I remember correctly.
> 
> When you pass in a string like this, only the pointer to the string is
> saved in the ring buffer. User space tools have no idea what those
> pointers are. The TPS() around strings maps those pointers to the
> string and shows them in the /sys/kernel/tracing/printk_formats file,
> such that perf and trace-cmd know how to make sense of those strings.

Makes sense. Quite a valuable feature!

thanks,

 - Joel