Re: [PATCH tip/core/rcu 20/45] torture: Include "Stopping" string to torture_kthread_stopping()

["Paul E. McKenney" <paulmck@linux.vnet.ibm.com>]

On Fri, May 09, 2014 at 05:16:57PM -0700, Josh Triplett wrote:
> On Fri, May 09, 2014 at 05:13:46PM -0700, Paul E. McKenney wrote:
> > On Wed, May 07, 2014 at 02:37:36PM -0700, josh@joshtriplett.org wrote:
> > > On Mon, Apr 28, 2014 at 05:25:08PM -0700, Paul E. McKenney wrote:
> > > > From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
> > > > 
> > > > Currently, torture_kthread_stopping() prints only the name of the
> > > > kthread that is stopping, which can be unedifying.  This commit therefore
> > > > adds "Stopping" to make things more evident.
> > > > 
> > > > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> > > 
> > > Feedback below.
> > > 
> > > >  kernel/torture.c | 5 ++++-
> > > >  1 file changed, 4 insertions(+), 1 deletion(-)
> > > > 
> > > > diff --git a/kernel/torture.c b/kernel/torture.c
> > > > index acc9afc2f26e..f329848c3eee 100644
> > > > --- a/kernel/torture.c
> > > > +++ b/kernel/torture.c
> > > > @@ -674,8 +674,11 @@ EXPORT_SYMBOL_GPL(torture_must_stop_irq);
> > > >   */
> > > >  void torture_kthread_stopping(char *title)
> > > >  {
> > > > +	char buf[128];
> > > > +
> > > > +	snprintf(buf, sizeof(buf), "Stopping %s", title);
> > > >  	if (verbose)
> > > > -		VERBOSE_TOROUT_STRING(title);
> > > > +		VERBOSE_TOROUT_STRING(buf);
> > > 
> > > This seems like a case where the macro has led to poorer code; rather
> > > than using sprintf into a temporary buffer, this should just print.
> > > Please consider fixing the output macros to allow formats, as the pr_*
> > > macros do.
> > > 
> > > Also, why do you need "if (verbose)" if the name of the macro has
> > > VERBOSE_ in it; shouldn't that mean it checks verbosity itself?
> > > (Another good reason not to create a unique verbosity level mechanism,
> > > and to use the kernel mechanisms instead.)
> > 
> > Good catch, removed the redundant "if (verbose)".
> > 
> > My attempts in the past to leverage existing in-kernel verbosity controls
> > has caused problems such as the output appearing or not depending on
> > the distro in question.
> 
> That aside, though, what do you think about making the macros accept
> format strings and arguments, in the style of pr_* and pr_fmt?

If I end up needing this in a few more cases, then it would indeed be
worth it.

							Thanx, Paul