Messages in this thread | | | Date | Wed, 29 Oct 2014 11:57:04 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH tip/core/rcu 9/9] rcu: Provide counterpart to rcu_dereference() for non-RCU situations |
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On Tue, Oct 28, 2014 at 03:10:02PM -0700, Paul E. McKenney wrote: > From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> > > Although rcu_dereference() and friends can be used in situations where > object lifetimes are being managed by something other than RCU, the > resulting sparse and lockdep-RCU noise can be annoying. This commit > therefore supplies a lockless_dereference(), which provides the > protection for dereferences without the RCU-related debugging noise. > > Reported-by: Al Viro <viro@ZenIV.linux.org.uk> > Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> > ---
> +#define lockless_dereference(p) \ > +({ \ > + typeof(p) _________p1 = ACCESS_ONCE(p); \ > + smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ > + (_________p1); \ > +})
Should we not have at least a single user along with this?
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