Re: [PATCH v2 tip/core/rcu 02/18] lockdep: Make RCU suspicious-access splats use pr_err

Paul E. McKenney
2017-01-24T00:14:04Z

On Mon, Jan 23, 2017 at 02:33:19PM -0800, Josh Triplett wrote:
> On Mon, Jan 23, 2017 at 11:30:16AM -0800, Paul E. McKenney wrote:
> > On Sat, Jan 21, 2017 at 12:40:23PM -0800, Josh Triplett wrote:
> > > On Tue, Jan 17, 2017 at 06:53:41PM -0800, Paul E. McKenney wrote:
> > > > This commit switches RCU suspicious-access splats use pr_err()
> > > > instead of the current INFO printk()s. This change makes it easier
> > > > to automatically classify splats.
> > > >
> > > > Reported-by: Dmitry Vyukov <dvyukov@google.com>
> > > > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
> > > > ---
> > > > kernel/locking/lockdep.c | 12 ++++++------
> > > > 1 file changed, 6 insertions(+), 6 deletions(-)
> > > >
> > > > diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c
> > > > index 7c38f8f3d97b..a74c0630172a 100644
> > > > --- a/kernel/locking/lockdep.c
> > > > +++ b/kernel/locking/lockdep.c
> > > > @@ -4412,13 +4412,13 @@ void lockdep_rcu_suspicious(const char *file, const int line, const char *s)
> > > > #endif /* #ifdef CONFIG_PROVE_RCU_REPEATEDLY */
> > > > /* Note: the following can be executed concurrently, so be careful. */
> > > > printk("\n");
> > > > - printk("===============================\n");
> > > > - printk("[ INFO: suspicious RCU usage. ]\n");
> > > > + pr_err("===============================\n");
> > > > + pr_err("[ suspicious RCU usage. ]\n");
> > >
> > > While re-adding the square bracket makes it symmetric, this change still
> > > seems odd, and unrelated to the switch to pr_err. You could change it
> > > to "ERR:" if you want, if "INFO:" feels inaccurate to you.
> >
> > So this would be OK?
> >
> > pr_err("[ ERR: suspicious RCU usage. ]\n");
> >
> > (Changed to this as a best guess, but please let me know.)
>
> Yeah, that seems fine. Sorry to nitpick this; it just otherwise seemed
> entirely unrelated to the rest of the change.

Might as well get it right... ;-)

Thanx, Paul