Re: [PATCH 1/3] tools: memory-model: Prepare for data-race detection

From: Alan Stern
Date: Wed Apr 24 2019 - 10:24:45 EST


On Wed, 24 Apr 2019, Paul E. McKenney wrote:

> On Mon, Apr 22, 2019 at 12:17:45PM -0400, Alan Stern wrote:
> > This patch makes some slight alterations to linux-kernel.cat in
> > preparation for adding support for data-race detection to the
> > Linux-Kernel Memory Model.
> >
> > The definitions of relations involved in Acquire, Release, and
> > unlock-lock ordering are moved up earlier in the source file.
> >
> > The rmb relation is factored through the new R4rmb class: the
> > class of reads to which rmb will apply.
> >
> > The definition of the fence relation is moved earlier, and it
> > is split up into read- and write-fences (rmb and wmb) and all
> > the others.
> >
> > This should not make any functional changes.
> >
> > Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
>
> Thank you, Alan, I have queued all three onto -rcu for review and testing.
> FYI, I rebased my smp_mb__{before,after}_atomic() patch on top of yours
> to avoid the conflict.
>
> Which demonstrates non-commutativity of patches. Your patches conflict
> with mine, but mine does not conflict with yours. ;-)

:-)

Besides, who knows where we'll end up with the
smp_mb__{before,after}_atomic stuff once Peter is done with it, anyway?

Alan