From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 02522C7618E for ; Fri, 21 Apr 2023 23:02:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233702AbjDUXCX (ORCPT ); Fri, 21 Apr 2023 19:02:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52626 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233520AbjDUXCT (ORCPT ); Fri, 21 Apr 2023 19:02:19 -0400 Received: from mail.netfilter.org (mail.netfilter.org [217.70.188.207]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 92B8DE57; Fri, 21 Apr 2023 16:02:18 -0700 (PDT) From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com Subject: [PATCH net-next 03/20] netfilter: nf_tables: don't store address of last rule on jump Date: Sat, 22 Apr 2023 01:01:54 +0200 Message-Id: <20230421230211.214635-4-pablo@netfilter.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230421230211.214635-1-pablo@netfilter.org> References: <20230421230211.214635-1-pablo@netfilter.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Florian Westphal Walk the rule headers until the trailer one (last_bit flag set) instead of stopping at last_rule address. This avoids the need to store the address when jumping to another chain. This cuts size of jumpstack array by one third, on 64bit from 384 to 256 bytes. Still, stack usage is still quite large: scripts/stackusage: nf_tables_core.c:258 nft_do_chain 496 static Next patch will also remove chain pointer. Signed-off-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- net/netfilter/nf_tables_core.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/net/netfilter/nf_tables_core.c b/net/netfilter/nf_tables_core.c index 6ecd0ba2e546..ec3bab751092 100644 --- a/net/netfilter/nf_tables_core.c +++ b/net/netfilter/nf_tables_core.c @@ -205,7 +205,6 @@ static noinline void nft_update_chain_stats(const struct nft_chain *chain, struct nft_jumpstack { const struct nft_chain *chain; const struct nft_rule_dp *rule; - const struct nft_rule_dp *last_rule; }; static void expr_call_ops_eval(const struct nft_expr *expr, @@ -259,9 +258,9 @@ unsigned int nft_do_chain(struct nft_pktinfo *pkt, void *priv) { const struct nft_chain *chain = priv, *basechain = chain; - const struct nft_rule_dp *rule, *last_rule; const struct net *net = nft_net(pkt); const struct nft_expr *expr, *last; + const struct nft_rule_dp *rule; struct nft_regs regs = {}; unsigned int stackptr = 0; struct nft_jumpstack jumpstack[NFT_JUMP_STACK_SIZE]; @@ -279,10 +278,9 @@ nft_do_chain(struct nft_pktinfo *pkt, void *priv) blob = rcu_dereference(chain->blob_gen_0); rule = (struct nft_rule_dp *)blob->data; - last_rule = (void *)blob->data + blob->size; next_rule: regs.verdict.code = NFT_CONTINUE; - for (; rule < last_rule; rule = nft_rule_next(rule)) { + for (; !rule->is_last ; rule = nft_rule_next(rule)) { nft_rule_dp_for_each_expr(expr, last, rule) { if (expr->ops == &nft_cmp_fast_ops) nft_cmp_fast_eval(expr, ®s); @@ -327,7 +325,6 @@ nft_do_chain(struct nft_pktinfo *pkt, void *priv) return NF_DROP; jumpstack[stackptr].chain = chain; jumpstack[stackptr].rule = nft_rule_next(rule); - jumpstack[stackptr].last_rule = last_rule; stackptr++; fallthrough; case NFT_GOTO: @@ -344,7 +341,6 @@ nft_do_chain(struct nft_pktinfo *pkt, void *priv) stackptr--; chain = jumpstack[stackptr].chain; rule = jumpstack[stackptr].rule; - last_rule = jumpstack[stackptr].last_rule; goto next_rule; } -- 2.30.2