Re: [patch 24/52] fs: dcache reduce d_parent locking

Peter Zijlstra
2010-06-24T08:44:30Z

On Thu, 2010-06-24 at 13:02 +1000, npiggin@suse.de wrote:
> Use RCU property of dcache to simplify locking in some places where we
> take d_parent and d_lock.
>
> Comment: don't need rcu_deref because we take the spinlock and recheck it.

But does the LOCK barrier imply a DATA DEPENDENCY barrier? (It does on
x86, and the compiler barrier implied by spin_lock() suffices to replace
ACCESS_ONCE()).