From patchwork Wed Mar 4 22:58:19 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Duyck X-Patchwork-Id: 446471 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 5DE02140161 for ; Thu, 5 Mar 2015 09:58:29 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753443AbbCDW6Y (ORCPT ); Wed, 4 Mar 2015 17:58:24 -0500 Received: from mx1.redhat.com ([209.132.183.28]:44230 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750811AbbCDW6V (ORCPT ); Wed, 4 Mar 2015 17:58:21 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id t24MwKnG024392 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Wed, 4 Mar 2015 17:58:20 -0500 Received: from [192.168.122.173] (ovpn-112-75.phx2.redhat.com [10.3.112.75]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t24MwJsV029271; Wed, 4 Mar 2015 17:58:19 -0500 Subject: [net-next PATCH v2 1/8] fib_trie: Only resize tnodes once instead of on each leaf removal in fib_table_flush From: Alexander Duyck To: netdev@vger.kernel.org Cc: davem@davemloft.net Date: Wed, 04 Mar 2015 14:58:19 -0800 Message-ID: <20150304225801.1612.52520.stgit@ahduyck-vm-fedora20> In-Reply-To: <20150304225459.1612.45514.stgit@ahduyck-vm-fedora20> References: <20150304225459.1612.45514.stgit@ahduyck-vm-fedora20> User-Agent: StGit/0.17-dirty MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org This change makes it so that we only call resize on the tnodes, instead of from each of the leaves. By doing this we can significantly reduce the amount of time spent resizing as we can update all of the leaves in the tnode first before we make any determinations about resizing. As a result we can simply free the tnode in the case that all of the leaves from a given tnode are flushed instead of resizing with each leaf removed. Signed-off-by: Alexander Duyck --- net/ipv4/fib_trie.c | 141 ++++++++++++++++++++++++++++----------------------- 1 file changed, 78 insertions(+), 63 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index f485345..d8b68b4 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -1400,25 +1400,6 @@ found: EXPORT_SYMBOL_GPL(fib_table_lookup); /* - * Remove the leaf and return parent. - */ -static void trie_leaf_remove(struct trie *t, struct tnode *l) -{ - struct tnode *tp = node_parent(l); - - pr_debug("entering trie_leaf_remove(%p)\n", l); - - if (tp) { - put_child(tp, get_index(l->key, tp), NULL); - trie_rebalance(t, tp); - } else { - RCU_INIT_POINTER(t->trie, NULL); - } - - node_free(l); -} - -/* * Caller must hold RTNL. */ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) @@ -1483,8 +1464,18 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) if (!plen) tb->tb_num_default--; - if (hlist_empty(&l->leaf)) - trie_leaf_remove(t, l); + if (hlist_empty(&l->leaf)) { + struct tnode *tp = node_parent(l); + + if (tp) { + put_child(tp, get_index(l->key, tp), NULL); + trie_rebalance(t, tp); + } else { + RCU_INIT_POINTER(t->trie, NULL); + } + + node_free(l); + } if (fa->fa_state & FA_S_ACCESSED) rt_cache_flush(cfg->fc_nlinfo.nl_net); @@ -1494,33 +1485,6 @@ int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) return 0; } -static int trie_flush_leaf(struct tnode *l) -{ - struct hlist_node *tmp; - unsigned char slen = 0; - struct fib_alias *fa; - int found = 0; - - hlist_for_each_entry_safe(fa, tmp, &l->leaf, fa_list) { - struct fib_info *fi = fa->fa_info; - - if (fi && (fi->fib_flags & RTNH_F_DEAD)) { - hlist_del_rcu(&fa->fa_list); - fib_release_info(fa->fa_info); - alias_free_mem_rcu(fa); - found++; - - continue; - } - - slen = fa->fa_slen; - } - - l->slen = slen; - - return found; -} - /* Scan for the next right leaf starting at node p->child[idx] * Since we have back pointer, no recursion necessary. */ @@ -1588,30 +1552,81 @@ static struct tnode *trie_leafindex(struct trie *t, int index) */ int fib_table_flush(struct fib_table *tb) { - struct trie *t = (struct trie *) tb->tb_data; - struct tnode *l, *ll = NULL; + struct trie *t = (struct trie *)tb->tb_data; + struct hlist_node *tmp; + struct fib_alias *fa; + struct tnode *n, *pn; + unsigned long cindex; + unsigned char slen; int found = 0; - for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) { - found += trie_flush_leaf(l); + n = rcu_dereference(t->trie); + if (!n) + goto flush_complete; + + pn = NULL; + cindex = 0; + + while (IS_TNODE(n)) { + /* record pn and cindex for leaf walking */ + pn = n; + cindex = 1ul << n->bits; +backtrace: + /* walk trie in reverse order */ + do { + while (!(cindex--)) { + t_key pkey = pn->key; + + n = pn; + pn = node_parent(n); + + /* resize completed node */ + resize(t, n); + + /* if we got the root we are done */ + if (!pn) + goto flush_complete; - if (ll) { - if (hlist_empty(&ll->leaf)) - trie_leaf_remove(t, ll); - else - leaf_pull_suffix(ll); + cindex = get_index(pkey, pn); + } + + /* grab the next available node */ + n = tnode_get_child(pn, cindex); + } while (!n); + } + + /* track slen in case any prefixes survive */ + slen = 0; + + hlist_for_each_entry_safe(fa, tmp, &n->leaf, fa_list) { + struct fib_info *fi = fa->fa_info; + + if (fi && (fi->fib_flags & RTNH_F_DEAD)) { + hlist_del_rcu(&fa->fa_list); + fib_release_info(fa->fa_info); + alias_free_mem_rcu(fa); + found++; + + continue; } - ll = l; + slen = fa->fa_slen; } - if (ll) { - if (hlist_empty(&ll->leaf)) - trie_leaf_remove(t, ll); - else - leaf_pull_suffix(ll); + /* update leaf slen */ + n->slen = slen; + + if (hlist_empty(&n->leaf)) { + put_child_root(pn, t, n->key, NULL); + node_free(n); + } else { + leaf_pull_suffix(n); } + /* if trie is leaf only loop is completed */ + if (pn) + goto backtrace; +flush_complete: pr_debug("trie_flush found=%d\n", found); return found; }