Re: [PATCH v2 tip/core/rcu 0/4] Documentation changes for 3.14

From: Josh Triplett
Date: Wed Dec 11 2013 - 23:10:57 EST


On Wed, Dec 11, 2013 at 03:08:23PM -0800, Paul E. McKenney wrote:
> Hello!
>
> This series once again attempts to improve rcu_assign_pointer()'s
> relationship with sparse.
>
> 1. Add a comment indicating that despite appearances,
> rcu_assign_pointer() really only evaluates its arguments once,
> as a cpp macro should.
>
> 2. Replace rcu_assign_pointer() of NULL with RCU_INIT_POINTER() to
> silence a sparse warning.
>
> 3. Apply ACCESS_ONCE() to rcu_assign_pointer()'s target to prevent
> comiler mischief. Also require that the source pointer be from
> the kernel address space. Sometimes it can be from the RCU address
> space, which necessitates the remaining patches in this series.
> Which, it must be admitted, apply to a very small fraction of
> the rcu_assign_pointer() invocations in the kernel. This commit
> courtesy of Josh Triplett.
>
> 4. Add an RCU_INITIALIZER() for compile-time initialization of
> global RCU-protected pointers.

For all the patches (other than the one I wrote, for obvious reasons):
Reviewed-by: Josh Triplett <josh@xxxxxxxxxxxxxxxx>
--
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/