Re: [PATCH RFC] mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU
From: Paul E. McKenney
Date: Wed Jan 25 2017 - 15:07:18 EST
On Wed, Jan 25, 2017 at 09:04:47AM -0800, Eric Dumazet wrote:
> On Wed, 2017-01-25 at 10:45 -0600, Christoph Lameter wrote:
> > On Sun, 22 Jan 2017, Paul E. McKenney wrote:
> > > On Wed, Jan 18, 2017 at 06:00:24PM -0600, Christoph Lameter wrote:
> > > > On Wed, 18 Jan 2017, Paul E. McKenney wrote:
> > > >
> > > > > Actually, slab is using RCU to provide type safety to those slab users
> > > > > who request it.
> > > >
> > > > Typesafety is a side effect. The main idea here is that the object can
> > > > still be accessed in RCU sections after another processor frees the
> > > > object. We guarantee that the object is not freed but it may be reused
> > > > for another object within the RCU period.
> > > >
> > > > Can we have a name that expresses all of that properly?
> > >
> > > But of course!!! "Type safety". http://wiki.c2.com/?TypeSafe
> > Well that does not convey the idea that RCU is involved here.
> > SLAB_DESTROY_RCU_TYPESAFE
> Not clear why we need to change this very fine name ?
> SLAB_DESTROY_BY_RCU was only used by few of us, we know damn well what
> it means.
> Consider we wont be able to change it in various web pages / archives /
The reason I proposed this change is that I ran into some people last
week who had burned some months learning that this very fine flag
provides only type safety, not identity safety.