From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: [PATCH net 13/13] net: sched: cls_u32: simplify the hell out u32_delete() emptiness check Date: Sun, 9 Sep 2018 02:31:32 +0100 Message-ID: <20180909013132.3222-14-viro@ZenIV.linux.org.uk> References: <20180909013132.3222-1-viro@ZenIV.linux.org.uk> Cc: Jamal Hadi Salim , Cong Wang , Jiri Pirko To: netdev@vger.kernel.org Return-path: Received: from zeniv.linux.org.uk ([195.92.253.2]:41092 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726084AbeIIG0m (ORCPT ); Sun, 9 Sep 2018 02:26:42 -0400 In-Reply-To: <20180909013132.3222-1-viro@ZenIV.linux.org.uk> Sender: netdev-owner@vger.kernel.org List-ID: From: Al Viro Now that we have the knode count, we can instantly check if any hnodes are non-empty. And that kills the check for extra references to root hnode - those could happen only if there was a knode to carry such a link. Signed-off-by: Al Viro --- net/sched/cls_u32.c | 48 +----------------------------------------------- 1 file changed, 1 insertion(+), 47 deletions(-) diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index 86cbe4f5800e..ef786ec24843 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -628,17 +628,6 @@ static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht, return -ENOENT; } -static bool ht_empty(struct tc_u_hnode *ht) -{ - unsigned int h; - - for (h = 0; h <= ht->divisor; h++) - if (rcu_access_pointer(ht->ht[h])) - return false; - - return true; -} - static void u32_destroy(struct tcf_proto *tp, struct netlink_ext_ack *extack) { struct tc_u_common *tp_c = tp->data; @@ -676,13 +665,9 @@ static int u32_delete(struct tcf_proto *tp, void *arg, bool *last, struct netlink_ext_ack *extack) { struct tc_u_hnode *ht = arg; - struct tc_u_hnode *root_ht = rtnl_dereference(tp->root); struct tc_u_common *tp_c = tp->data; int ret = 0; - if (ht == NULL) - goto out; - if (TC_U32_KEY(ht->handle)) { u32_remove_hw_knode(tp, (struct tc_u_knode *)ht, extack); ret = u32_delete_key(tp, (struct tc_u_knode *)ht); @@ -702,38 +687,7 @@ static int u32_delete(struct tcf_proto *tp, void *arg, bool *last, } out: - *last = true; - if (root_ht) { - if (root_ht->refcnt > 2) { - *last = false; - goto ret; - } - if (root_ht->refcnt == 2) { - if (!ht_empty(root_ht)) { - *last = false; - goto ret; - } - } - } - - if (tp_c->refcnt > 1) { - *last = false; - goto ret; - } - - if (tp_c->refcnt == 1) { - struct tc_u_hnode *ht; - - for (ht = rtnl_dereference(tp_c->hlist); - ht; - ht = rtnl_dereference(ht->next)) - if (!ht_empty(ht)) { - *last = false; - break; - } - } - -ret: + *last = tp_c->refcnt == 1 && tp_c->knodes == 0; return ret; } -- 2.11.0