From patchwork Sat Jun 1 03:36:10 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Ahern X-Patchwork-Id: 1108657 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=pass (p=none dis=none) header.from=kernel.org Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="VkLei1Bm"; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 45G6SH0dDNz9sNf for ; Sat, 1 Jun 2019 13:36:47 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727221AbfFADgp (ORCPT ); Fri, 31 May 2019 23:36:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:51456 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727038AbfFADgY (ORCPT ); Fri, 31 May 2019 23:36:24 -0400 Received: from kenny.it.cumulusnetworks.com. (fw.cumulusnetworks.com [216.129.126.126]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id E11E6270EB; Sat, 1 Jun 2019 03:36:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1559360184; bh=mUkLEvNC1/4GoUHViX/dV05mv5nw+CW2KWNe8+WFdLQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VkLei1Bm8EZ6MoHuuV88pcI/xttYzkarFyJhsbqYxH2sCJoWIMdP+0Qk2B601tQse K4rcOOchQzgFU9bJh1kEcDCISvQ+sKxuSjMvzAAxk/vsrcnPU+mFsU2x+0htATc0I+ yhSAYPNvgsTCo6ZrNnKQDya/XijBew4Vr6UbIGKM= From: David Ahern To: davem@davemloft.net, netdev@vger.kernel.org Cc: alexei.starovoitov@gmail.com, David Ahern Subject: [PATCH RFC net-next 19/27] ipv4: Optimization for fib_info lookup with nexthops Date: Fri, 31 May 2019 20:36:10 -0700 Message-Id: <20190601033618.27702-20-dsahern@kernel.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190601033618.27702-1-dsahern@kernel.org> References: <20190601033618.27702-1-dsahern@kernel.org> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: David Ahern Be optimistic about re-using a fib_info when nexthop id is given and the route does not use metrics. Avoids a memory allocation which in most cases is expected to be freed anyways. Signed-off-by: David Ahern --- net/ipv4/fib_semantics.c | 71 ++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 65 insertions(+), 6 deletions(-) diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c index 08bbdf3d5173..d9f8c3c0fb0d 100644 --- a/net/ipv4/fib_semantics.c +++ b/net/ipv4/fib_semantics.c @@ -329,14 +329,32 @@ static inline unsigned int fib_devindex_hashfn(unsigned int val) (val >> (DEVINDEX_HASHBITS * 2))) & mask; } -static inline unsigned int fib_info_hashfn(const struct fib_info *fi) +static unsigned int fib_info_hashfn_1(int init_val, u8 protocol, u8 scope, + u32 prefsrc, u32 priority) +{ + unsigned int val = init_val; + + val ^= (protocol << 8) | scope; + val ^= prefsrc; + val ^= priority; + + return val; +} + +static unsigned int fib_info_hashfn_result(unsigned int val) { unsigned int mask = (fib_info_hash_size - 1); - unsigned int val = fi->fib_nhs; - val ^= (fi->fib_protocol << 8) | fi->fib_scope; - val ^= (__force u32)fi->fib_prefsrc; - val ^= fi->fib_priority; + return (val ^ (val >> 7) ^ (val >> 12)) & mask; +} + +static inline unsigned int fib_info_hashfn(struct fib_info *fi) +{ + unsigned int val; + + val = fib_info_hashfn_1(fi->fib_nhs, fi->fib_protocol, + fi->fib_scope, (__force u32)fi->fib_prefsrc, + fi->fib_priority); if (fi->nh) { val ^= fib_devindex_hashfn(fi->nh->id); @@ -346,7 +364,40 @@ static inline unsigned int fib_info_hashfn(const struct fib_info *fi) } endfor_nexthops(fi) } - return (val ^ (val >> 7) ^ (val >> 12)) & mask; + return fib_info_hashfn_result(val); +} + +/* no metrics, only nexthop id */ +static struct fib_info *fib_find_info_nh(struct net *net, + const struct fib_config *cfg) +{ + struct hlist_head *head; + struct fib_info *fi; + unsigned int hash; + + hash = fib_info_hashfn_1(fib_devindex_hashfn(cfg->fc_nh_id), + cfg->fc_protocol, cfg->fc_scope, + (__force u32)cfg->fc_prefsrc, + cfg->fc_priority); + hash = fib_info_hashfn_result(hash); + head = &fib_info_hash[hash]; + + hlist_for_each_entry(fi, head, fib_hash) { + if (!net_eq(fi->fib_net, net)) + continue; + if (!fi->nh || fi->nh->id != cfg->fc_nh_id) + continue; + if (cfg->fc_protocol == fi->fib_protocol && + cfg->fc_scope == fi->fib_scope && + cfg->fc_prefsrc == fi->fib_prefsrc && + cfg->fc_priority == fi->fib_priority && + cfg->fc_type == fi->fib_type && + cfg->fc_table == fi->fib_tb_id && + !((cfg->fc_flags ^ fi->fib_flags) & ~RTNH_COMPARE_MASK)) + return fi; + } + + return NULL; } static struct fib_info *fib_find_info(struct fib_info *nfi) @@ -1313,6 +1364,14 @@ struct fib_info *fib_create_info(struct fib_config *cfg, } if (cfg->fc_nh_id) { + if (!cfg->fc_mx) { + fi = fib_find_info_nh(net, cfg); + if (fi) { + fi->fib_treeref++; + return fi; + } + } + nh = nexthop_find_by_id(net, cfg->fc_nh_id); if (!nh) { NL_SET_ERR_MSG(extack, "Nexthop id does not exist");