On 04/09/2015 04:14 PM, Peter Zijlstra wrote: > On Thu, Apr 09, 2015 at 04:09:07PM +0800, Lai Jiangshan wrote: >> On 04/09/2015 12:48 AM, Peter Zijlstra wrote: >> >>> + >>> +struct latch_tree_node { >>> + /* >>> + * Because we have an array of two entries in struct latch_tree_nodes >>> + * it's not possible to use container_of() to get back to the >>> + * encapsulating structure; therefore we have to put in a back pointer. >>> + */ >>> + void *priv; >>> + struct rb_node node; >>> +}; >> >> I don't think @priv is strictly needed. It is possible to use container_of() >> to go back. @priv is even not used in this file (except the initialization). >> >> First, we can use container_of() to find encapsulating structure from the >> struct latch_tree_nodeS. >> >> Second, we can add a @idx to __lt_insert() and __lt_find(), > > insert yes, find no. Remember that both nodes are in the _same_ tree. > > There is no way of knowing if a tree node is an init or core node while > iterating. > . >
This sentence is talking about module.c not latch_tree.h. So I guess it is user(module.c)'s problem, not latch_tree.h's problem. The user(module.c) can wrap the struct latch_tree_nodes and add @priv. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/