Re: [PATCH] tools/perf, rbtree: Add RCU wrappers to make rbtree.h usable in user-space

[Jon Christopherson]

On 07/03/2015 02:14 AM, Peter Zijlstra wrote:
> On Fri, Jul 03, 2015 at 06:21:12AM +0930, Rusty Russell wrote:
> > Looks like Peter Zijlstra is the one to take this fix...
>
> acme is the steward of tools/perf/

This is the full context of the patch mentioned:

https://lkml.org/lkml/2015/6/17/129

> > > > diff --git a/tools/perf/util/include/linux/rcupdate.h
> > > > b/tools/perf/util/include/linux/rcupdate.h
> > > > new file mode 100644
> > > > index 0000000..51c0f45
> > > > --- /dev/null
> > > > +++ b/tools/perf/util/include/linux/rcupdate.h
> > > > @@ -0,0 +1,9 @@
> > > > +#ifndef PERF_LINUX_RCUPDATE_H_
> > > > +#define PERF_LINUX_RCUPDATE_H_
> > > > +
> > > > +/* Simple trivial wrappers for now, we don't use RCU in perf user-space
> > > > (yet): */
> > > > +#define WRITE_ONCE(var, val) ((var) = (val))
>
> It looks like perf includes linux/compiler.h so it should already have this.
>
> > > > +#define rcu_assign_pointer(ptr, val) WRITE_ONCE(ptr, val)
>
> That's plain wrong, WRITE_ONCE(*(ptr), (val))

The original author of the patch appears to be Ingo. Syntax aside .. it 
solves the issue mentioned. Perhaps a corrected version could be 
included instead.

-Jon
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/