From patchwork Fri Mar 29 04:11:29 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Horman X-Patchwork-Id: 232272 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id BEA4C2C00BA for ; Fri, 29 Mar 2013 15:14:50 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755370Ab3C2EOh (ORCPT ); Fri, 29 Mar 2013 00:14:37 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:33657 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752646Ab3C2EL4 (ORCPT ); Fri, 29 Mar 2013 00:11:56 -0400 Received: from ayumi.akashicho.tokyo.vergenet.net (p8120-ipbfp1001kobeminato.hyogo.ocn.ne.jp [118.10.137.120]) by kirsty.vergenet.net (Postfix) with ESMTP id 4700026715D; Fri, 29 Mar 2013 15:11:55 +1100 (EST) Received: by ayumi.akashicho.tokyo.vergenet.net (Postfix, from userid 7100) id 2CEC8EDEA2C; Fri, 29 Mar 2013 13:11:53 +0900 (JST) From: Simon Horman To: Pablo Neira Ayuso Cc: lvs-devel@vger.kernel.org, netdev@vger.kernel.org, netfilter-devel@vger.kernel.org, Wensong Zhang , Julian Anastasov , Simon Horman Subject: [PATCH 12/34] ipvs: convert locks used in persistence engines Date: Fri, 29 Mar 2013 13:11:29 +0900 Message-Id: <1364530311-11512-13-git-send-email-horms@verge.net.au> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1364530311-11512-1-git-send-email-horms@verge.net.au> References: <1364530311-11512-1-git-send-email-horms@verge.net.au> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Julian Anastasov Allow the readers to use RCU lock and for PE module registrations use global mutex instead of spinlock. All PE modules need to use synchronize_rcu in their module exit handler. Signed-off-by: Julian Anastasov Signed-off by: Hans Schillstrom Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_pe.c | 43 +++++++++++-------------------------- net/netfilter/ipvs/ip_vs_pe_sip.c | 1 + 2 files changed, 14 insertions(+), 30 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_pe.c b/net/netfilter/ipvs/ip_vs_pe.c index 5cf859c..5d9774c 100644 --- a/net/netfilter/ipvs/ip_vs_pe.c +++ b/net/netfilter/ipvs/ip_vs_pe.c @@ -13,8 +13,8 @@ /* IPVS pe list */ static LIST_HEAD(ip_vs_pe); -/* lock for service table */ -static DEFINE_SPINLOCK(ip_vs_pe_lock); +/* semaphore for IPVS PEs. */ +static DEFINE_MUTEX(ip_vs_pe_mutex); /* Bind a service with a pe */ void ip_vs_bind_pe(struct ip_vs_service *svc, struct ip_vs_pe *pe) @@ -36,9 +36,8 @@ struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name) IP_VS_DBG(10, "%s(): pe_name \"%s\"\n", __func__, pe_name); - spin_lock_bh(&ip_vs_pe_lock); - - list_for_each_entry(pe, &ip_vs_pe, n_list) { + rcu_read_lock(); + list_for_each_entry_rcu(pe, &ip_vs_pe, n_list) { /* Test and get the modules atomically */ if (pe->module && !try_module_get(pe->module)) { @@ -47,14 +46,14 @@ struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name) } if (strcmp(pe_name, pe->name)==0) { /* HIT */ - spin_unlock_bh(&ip_vs_pe_lock); + rcu_read_unlock(); return pe; } if (pe->module) module_put(pe->module); } + rcu_read_unlock(); - spin_unlock_bh(&ip_vs_pe_lock); return NULL; } @@ -83,22 +82,13 @@ int register_ip_vs_pe(struct ip_vs_pe *pe) /* increase the module use count */ ip_vs_use_count_inc(); - spin_lock_bh(&ip_vs_pe_lock); - - if (!list_empty(&pe->n_list)) { - spin_unlock_bh(&ip_vs_pe_lock); - ip_vs_use_count_dec(); - pr_err("%s(): [%s] pe already linked\n", - __func__, pe->name); - return -EINVAL; - } - + mutex_lock(&ip_vs_pe_mutex); /* Make sure that the pe with this name doesn't exist * in the pe list. */ list_for_each_entry(tmp, &ip_vs_pe, n_list) { if (strcmp(tmp->name, pe->name) == 0) { - spin_unlock_bh(&ip_vs_pe_lock); + mutex_unlock(&ip_vs_pe_mutex); ip_vs_use_count_dec(); pr_err("%s(): [%s] pe already existed " "in the system\n", __func__, pe->name); @@ -106,8 +96,8 @@ int register_ip_vs_pe(struct ip_vs_pe *pe) } } /* Add it into the d-linked pe list */ - list_add(&pe->n_list, &ip_vs_pe); - spin_unlock_bh(&ip_vs_pe_lock); + list_add_rcu(&pe->n_list, &ip_vs_pe); + mutex_unlock(&ip_vs_pe_mutex); pr_info("[%s] pe registered.\n", pe->name); @@ -118,17 +108,10 @@ EXPORT_SYMBOL_GPL(register_ip_vs_pe); /* Unregister a pe from the pe list */ int unregister_ip_vs_pe(struct ip_vs_pe *pe) { - spin_lock_bh(&ip_vs_pe_lock); - if (list_empty(&pe->n_list)) { - spin_unlock_bh(&ip_vs_pe_lock); - pr_err("%s(): [%s] pe is not in the list. failed\n", - __func__, pe->name); - return -EINVAL; - } - + mutex_lock(&ip_vs_pe_mutex); /* Remove it from the d-linked pe list */ - list_del(&pe->n_list); - spin_unlock_bh(&ip_vs_pe_lock); + list_del_rcu(&pe->n_list); + mutex_unlock(&ip_vs_pe_mutex); /* decrease the module use count */ ip_vs_use_count_dec(); diff --git a/net/netfilter/ipvs/ip_vs_pe_sip.c b/net/netfilter/ipvs/ip_vs_pe_sip.c index 12475ef..00cc024 100644 --- a/net/netfilter/ipvs/ip_vs_pe_sip.c +++ b/net/netfilter/ipvs/ip_vs_pe_sip.c @@ -172,6 +172,7 @@ static int __init ip_vs_sip_init(void) static void __exit ip_vs_sip_cleanup(void) { unregister_ip_vs_pe(&ip_vs_sip_pe); + synchronize_rcu(); } module_init(ip_vs_sip_init);