Re: [RFC][PATCH 4/4] futex: Rewrite FUTEX_UNLOCK_PI
From: Peter Zijlstra
Date: Mon Oct 03 2016 - 11:45:32 EST
On Mon, Oct 03, 2016 at 11:36:24AM -0400, Steven Rostedt wrote:
> > + WARN_ON_ONCE(!atomic_inc_not_zero(&pi_state->refcount));
>
> Don't we have a rule where WARN_ON() and BUG_ON() should never have
> "side effects"? That is, they should only check values, but their
> contents should not update values.
not that I'm aware, there's various places in the kernel (including
kref.h) that relies on WARN_ON*() having side effects.