On 05/28/2015 06:13 PM, Eric Dumazet wrote: > This patch is not needed. > > You really should read Documentation/RCU , because it looks like you are > quite confused. > > When we remove an element from a RCU protected list, all the objects in > the chain are already ready to be caught by rcu readers. > > Therefore, no additional memory barrier is needed before doing *np = > n->next; > > Please do not add spurious memory barriers. Like atomic operations, we > want all of them being required and possibly documented.
Yes, you are right, thanks for your clear explanation :) However, there are still three places where we use rcu_assign_pointer() to remove a neigh entry from a RCU-protected list, and the three places are neigh_forced_gc(), neigh_flush_dev(), and __neigh_for_each_release() respectively. This means it's redundant for us to use rcu_assign_pointer() in the three places, right? Regards, Ying -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
