Messages in this thread | | | Subject | Re: [PATCH] NFS: Fix RCU warnings in nfs_inode_return_delegation_noreclaim() [ver #2] | From | Eric Dumazet <> | Date | Mon, 29 Mar 2010 22:26:40 +0200 |
| |
Le lundi 29 mars 2010 à 21:15 +0100, David Howells a écrit : > My objection to using rcu_dereference_check() here is that it's a dynamic > check: the compiler emits code to do it, since the lock/unlock status of what > the pointer points to cannot be determined easily at compiler time - and then > the barrier is interpolated anyway unnecessarily. >
Then in this case, use either a condition ORing all possibilities, or just use rcu_dereference_raw() because its just too complex ?
ptr = rcu_dereference_check(xxx->ptr, rcu_read_lock_held() || lockdep_is_held(&some_global_lock) || lockdep_is_held(&xxx->lock));
OR
/* This is too complex to check what protects us at this point */ ptr = rcu_dereference_raw(xxx->ptr);
-- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |