From 47a1a1d4be2910b13a8e90f75c17e253c39531ff Mon Sep 17 00:00:00 2001 From: Patrick McHardy Date: Wed, 19 Nov 2008 08:03:09 +0000 Subject: pkt_sched: remove unnecessary xchg() in packet classifiers The use of xchg() hasn't been necessary since 2.2.something when proper locking was added to packet schedulers. In the case of classifiers they mostly weren't even necessary before that since they're mainly used to assign a NULL pointer to the filter root in the ->destroy path; the root is destroyed immediately after that. Signed-off-by: Patrick McHardy Signed-off-by: David S. Miller --- net/sched/cls_u32.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'net/sched/cls_u32.c') diff --git a/net/sched/cls_u32.c b/net/sched/cls_u32.c index 246f9065ce3..05d178008cb 100644 --- a/net/sched/cls_u32.c +++ b/net/sched/cls_u32.c @@ -387,7 +387,7 @@ static int u32_destroy_hnode(struct tcf_proto *tp, struct tc_u_hnode *ht) static void u32_destroy(struct tcf_proto *tp) { struct tc_u_common *tp_c = tp->data; - struct tc_u_hnode *root_ht = xchg(&tp->root, NULL); + struct tc_u_hnode *root_ht = tp->root; WARN_ON(root_ht == NULL); @@ -479,7 +479,7 @@ static int u32_set_parms(struct tcf_proto *tp, unsigned long base, err = -EINVAL; if (tb[TCA_U32_LINK]) { u32 handle = nla_get_u32(tb[TCA_U32_LINK]); - struct tc_u_hnode *ht_down = NULL; + struct tc_u_hnode *ht_down = NULL, *ht_old; if (TC_U32_KEY(handle)) goto errout; @@ -493,11 +493,12 @@ static int u32_set_parms(struct tcf_proto *tp, unsigned long base, } tcf_tree_lock(tp); - ht_down = xchg(&n->ht_down, ht_down); + ht_old = n->ht_down; + n->ht_down = ht_down; tcf_tree_unlock(tp); - if (ht_down) - ht_down->refcnt--; + if (ht_old) + ht_old->refcnt--; } if (tb[TCA_U32_CLASSID]) { n->res.classid = nla_get_u32(tb[TCA_U32_CLASSID]); -- cgit v1.2.3