From patchwork Tue Aug 17 15:23:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yajun Deng X-Patchwork-Id: 498602 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, URIBL_BLOCKED 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 A42B1C4338F for ; Tue, 17 Aug 2021 15:23:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D5C960E09 for ; Tue, 17 Aug 2021 15:23:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237909AbhHQPX4 (ORCPT ); Tue, 17 Aug 2021 11:23:56 -0400 Received: from out1.migadu.com ([91.121.223.63]:42403 "EHLO out1.migadu.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232675AbhHQPXs (ORCPT ); Tue, 17 Aug 2021 11:23:48 -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=1629213791; 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=YRDIrpoiP2TYN2AF9kIZ6gsIKbpG8tdAdC94qhQeGU4=; b=SJSJxx0/SDXGehEa6vbS1gq2dZe/5Q0+y8vuNpChZK/alzDG/S55UM7AC32QixiwuoFMa6 IHr5BBqzBKZrBFQfXhdu5Zc+aWh59/Rd6I6K7StaimCFO9i4Eb062w51GVjiY05PbDCemm kUTWrTGuDD3hEtvF0xtZTvXE3Ht1pMI= 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 v2] net: net_namespace: Optimize the code Date: Tue, 17 Aug 2021 23:23:00 +0800 Message-Id: <20210817152300.10698-1-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 There is only one caller for ops_free(), so inline it. 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. ==================== v2: - v1 does not apply, rebase it. ==================== Signed-off-by: Yajun Deng --- net/core/net_namespace.c | 52 +++++++++++++++++++--------------------- 1 file changed, 24 insertions(+), 28 deletions(-) diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c index 9b5a767eddd5..a448a9b5bb2d 100644 --- a/net/core/net_namespace.c +++ b/net/core/net_namespace.c @@ -98,7 +98,7 @@ static int net_assign_generic(struct net *net, unsigned int id, void *data) } ng = net_alloc_generic(); - if (ng == NULL) + if (!ng) return -ENOMEM; /* @@ -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 +426,18 @@ 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); } struct net *copy_net_ns(unsigned long flags, @@ -479,7 +475,7 @@ 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 +607,7 @@ 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 +1116,14 @@ 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 +1149,7 @@ 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 +1162,8 @@ 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 +1186,7 @@ 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); } }