From patchwork Tue Aug 17 10:20:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yajun Deng X-Patchwork-Id: 499653 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 61C73C4338F for ; Tue, 17 Aug 2021 10:20:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 43BA360232 for ; Tue, 17 Aug 2021 10:20:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236220AbhHQKVZ (ORCPT ); Tue, 17 Aug 2021 06:21:25 -0400 Received: from out2.migadu.com ([188.165.223.204]:13895 "EHLO out2.migadu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235651AbhHQKVK (ORCPT ); Tue, 17 Aug 2021 06:21:10 -0400 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1629195634; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=oRyPuKKOBakVGi7BzUz0aCZ6qjxSBDTY/WItFLOtqAU=; b=LkfBcz0snirdno7/M/htlIRw+ZadPgi00aa+0mB7opgr2/3lmOqog4nT8ph7zHD2+5rUtN nNWp+bJHrf1JjTlay7rq9gsJ2VAyXpl4O8o/dDMPPrv4e/YY/qAuOOe7vZ9+hb8OM5cRng aFC3yAdprLK8ipIIbcWgKA/bCnphtAI= From: Yajun Deng To: davem@davemloft.net, kuba@kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Yajun Deng Subject: [PATCH net-next] net: net_namespace: Optimize the code Date: Tue, 17 Aug 2021 18:20:01 +0800 Message-Id: <20210817102001.1125-1-yajun.deng@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: yajun.deng@linux.dev Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Inline ops_free(), becase there is only one caller. Separate net_drop_ns() and net_free(), so the net_free() can be called directly. Add free_exit_list() helper function for free net_exit_list. Signed-off-by: Yajun Deng --- net/core/net_namespace.c | 49 ++++++++++++++++++---------------------- 1 file changed, 22 insertions(+), 27 deletions(-) struct net *copy_net_ns(unsigned long flags, @@ -479,7 +474,7 @@ struct net *copy_net_ns(unsigned long flags, put_userns: key_remove_domain(net->key_domain); put_user_ns(user_ns); - net_drop_ns(net); + net_free(net); dec_ucounts: dec_net_namespaces(ucounts); return ERR_PTR(rv); @@ -611,7 +606,7 @@ static void cleanup_net(struct work_struct *work) dec_net_namespaces(net->ucounts); key_remove_domain(net->key_domain); put_user_ns(net->user_ns); - net_drop_ns(net); + net_free(net); } } @@ -1120,6 +1115,14 @@ static int __init net_ns_init(void) pure_initcall(net_ns_init); +static void free_exit_list(struct pernet_operations *ops, struct list_head *net_exit_list) +{ + ops_pre_exit_list(ops, net_exit_list); + synchronize_rcu(); + ops_exit_list(ops, net_exit_list); + ops_free_list(ops, net_exit_list); +} + #ifdef CONFIG_NET_NS static int __register_pernet_operations(struct list_head *list, struct pernet_operations *ops) @@ -1145,10 +1148,7 @@ static int __register_pernet_operations(struct list_head *list, out_undo: /* If I have an error cleanup all namespaces I initialized */ list_del(&ops->list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + free_exit_list(ops, &net_exit_list); return error; } @@ -1161,10 +1161,8 @@ static void __unregister_pernet_operations(struct pernet_operations *ops) /* See comment in __register_pernet_operations() */ for_each_net(net) list_add_tail(&net->exit_list, &net_exit_list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + + free_exit_list(ops, &net_exit_list); } #else @@ -1187,10 +1185,7 @@ static void __unregister_pernet_operations(struct pernet_operations *ops) } else { LIST_HEAD(net_exit_list); list_add(&init_net.exit_list, &net_exit_list); - ops_pre_exit_list(ops, &net_exit_list); - synchronize_rcu(); - ops_exit_list(ops, &net_exit_list); - ops_free_list(ops, &net_exit_list); + free_exit_list(ops, &net_exit_list); } } diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 9b5a767eddd5..27acbf2df78f 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -148,13 +148,6 @@ static int ops_init(const struct pernet_operations *ops, struct net *net) return err; } -static void ops_free(const struct pernet_operations *ops, struct net *net) -{ - if (ops->id && ops->size) { - kfree(net_generic(net, *ops->id)); - } -} - static void ops_pre_exit_list(const struct pernet_operations *ops, struct list_head *net_exit_list) { @@ -184,7 +177,7 @@ static void ops_free_list(const struct pernet_operations *ops, struct net *net; if (ops->size && ops->id) { list_for_each_entry(net, net_exit_list, exit_list) - ops_free(ops, net); + kfree(net_generic(net, *ops->id)); } } @@ -433,15 +426,17 @@ static struct net *net_alloc(void) static void net_free(struct net *net) { - kfree(rcu_access_pointer(net->gen)); - kmem_cache_free(net_cachep, net); + if (refcount_dec_and_test(&net->passive)) { + kfree(rcu_access_pointer(net->gen)); + kmem_cache_free(net_cachep, net); + } } void net_drop_ns(void *p) { - struct net *ns = p; - if (ns && refcount_dec_and_test(&ns->passive)) - net_free(ns); + struct net *net = (struct net *)p; + if (net) + net_free(net); }