From patchwork Sat Apr 6 12:17:30 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pablo Neira Ayuso X-Patchwork-Id: 234390 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 C84732C0116 for ; Sat, 6 Apr 2013 23:21:02 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1163500Ab3DFMUv (ORCPT ); Sat, 6 Apr 2013 08:20:51 -0400 Received: from mail.us.es ([193.147.175.20]:39000 "EHLO mail.us.es" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163439Ab3DFMSj (ORCPT ); Sat, 6 Apr 2013 08:18:39 -0400 Received: (qmail 29177 invoked from network); 6 Apr 2013 14:18:38 +0200 Received: from unknown (HELO us.es) (192.168.2.12) by us.es with SMTP; 6 Apr 2013 14:18:38 +0200 Received: (qmail 5893 invoked by uid 507); 6 Apr 2013 12:18:38 -0000 X-Qmail-Scanner-Diagnostics: from 127.0.0.1 by antivirus2 (envelope-from , uid 501) with qmail-scanner-2.10 (clamdscan: 0.97.7/16967. spamassassin: 3.3.2. 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Processed in 2.524348 secs); 06 Apr 2013 12:18:38 -0000 X-Spam-Checker-Version: SpamAssassin 3.3.2 (2011-06-06) on antivirus2 X-Spam-Level: X-Spam-Status: No, score=-98.6 required=7.5 tests=BAYES_50, RCVD_IN_SORBS_DUL, USER_IN_WHITELIST autolearn=disabled version=3.3.2 X-Envelope-From: pablo@netfilter.org Received: from unknown (HELO antivirus2) (127.0.0.1) by us.es with SMTP; 6 Apr 2013 12:18:35 -0000 Received: from 192.168.1.13 (192.168.1.13) by antivirus2 (F-Secure/fsigk_smtp/407/antivirus2); Sat, 06 Apr 2013 14:18:35 +0200 (CEST) X-Virus-Status: clean(F-Secure/fsigk_smtp/407/antivirus2) Received: (qmail 7645 invoked from network); 6 Apr 2013 14:18:35 +0200 Received: from dhcp103.vr.in-berlin.de (HELO soleta.in-berlin.de) (pneira@us.es@217.197.81.103) by us.es with SMTP; 6 Apr 2013 14:18:35 +0200 From: Pablo Neira Ayuso To: netfilter-devel@vger.kernel.org Cc: davem@davemloft.net, netdev@vger.kernel.org Subject: [PATCH 31/51] ipvs: convert dests to rcu Date: Sat, 6 Apr 2013 14:17:30 +0200 Message-Id: <1365250670-14993-32-git-send-email-pablo@netfilter.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1365250670-14993-1-git-send-email-pablo@netfilter.org> References: <1365250670-14993-1-git-send-email-pablo@netfilter.org> Sender: netfilter-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org From: Julian Anastasov In previous commits the schedulers started to access svc->destinations with _rcu list traversal primitives because the IP_VS_WAIT_WHILE macro still plays the role of grace period. Now it is time to finish the updating part, i.e. adding and deleting of dests with _rcu suffix before removing the IP_VS_WAIT_WHILE in next commit. We use the same rule for conns as for the schedulers: dests can be searched in RCU read-side critical section where ip_vs_dest_hold can be called by ip_vs_bind_dest. Some things are not perfect, for example, calling functions like ip_vs_lookup_dest from updating code under RCU, just because we use some function both from reader and from updater. Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- include/net/ip_vs.h | 2 +- net/netfilter/ipvs/ip_vs_conn.c | 8 +++++--- net/netfilter/ipvs/ip_vs_ctl.c | 32 +++++++++++++++++--------------- net/netfilter/ipvs/ip_vs_sync.c | 11 ++++------- 4 files changed, 27 insertions(+), 26 deletions(-) diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 4a7bc63..78a6634 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -1434,7 +1434,7 @@ extern struct ip_vs_dest * ip_vs_find_dest(struct net *net, int af, const union nf_inet_addr *daddr, __be16 dport, const union nf_inet_addr *vaddr, __be16 vport, __u16 protocol, __u32 fwmark, __u32 flags); -extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp); +extern void ip_vs_try_bind_dest(struct ip_vs_conn *cp); static inline void ip_vs_dest_hold(struct ip_vs_dest *dest) { diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index 1b29e4a..54de340 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -611,10 +611,11 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest) * Check if there is a destination for the connection, if so * bind the connection to the destination. */ -struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp) +void ip_vs_try_bind_dest(struct ip_vs_conn *cp) { struct ip_vs_dest *dest; + rcu_read_lock(); dest = ip_vs_find_dest(ip_vs_conn_net(cp), cp->af, &cp->daddr, cp->dport, &cp->vaddr, cp->vport, cp->protocol, cp->fwmark, cp->flags); @@ -624,7 +625,8 @@ struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp) spin_lock(&cp->lock); if (cp->dest) { spin_unlock(&cp->lock); - return dest; + rcu_read_unlock(); + return; } /* Applications work depending on the forwarding method @@ -648,7 +650,7 @@ struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp) if (pd && atomic_read(&pd->appcnt)) ip_vs_bind_app(cp, pd->pp); } - return dest; + rcu_read_unlock(); } diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 2bfd807..0763cc6 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -565,8 +565,8 @@ bool ip_vs_has_real_service(struct net *net, int af, __u16 protocol, return false; } -/* - * Lookup destination by {addr,port} in the given service +/* Lookup destination by {addr,port} in the given service + * Called under RCU lock. */ static struct ip_vs_dest * ip_vs_lookup_dest(struct ip_vs_service *svc, const union nf_inet_addr *daddr, @@ -577,7 +577,7 @@ ip_vs_lookup_dest(struct ip_vs_service *svc, const union nf_inet_addr *daddr, /* * Find the destination for the given service */ - list_for_each_entry(dest, &svc->destinations, n_list) { + list_for_each_entry_rcu(dest, &svc->destinations, n_list) { if ((dest->af == svc->af) && ip_vs_addr_equal(svc->af, &dest->addr, daddr) && (dest->port == dport)) { @@ -591,10 +591,11 @@ ip_vs_lookup_dest(struct ip_vs_service *svc, const union nf_inet_addr *daddr, /* * Find destination by {daddr,dport,vaddr,protocol} - * Cretaed to be used in ip_vs_process_message() in + * Created to be used in ip_vs_process_message() in * the backup synchronization daemon. It finds the * destination to be bound to the received connection * on the backup. + * Called under RCU lock, no refcnt is returned. */ struct ip_vs_dest *ip_vs_find_dest(struct net *net, int af, const union nf_inet_addr *daddr, @@ -615,8 +616,6 @@ struct ip_vs_dest *ip_vs_find_dest(struct net *net, int af, dest = ip_vs_lookup_dest(svc, daddr, port); if (!dest) dest = ip_vs_lookup_dest(svc, daddr, port ^ dport); - if (dest) - ip_vs_dest_hold(dest); ip_vs_service_put(svc); return dest; } @@ -826,7 +825,7 @@ __ip_vs_update_dest(struct ip_vs_service *svc, struct ip_vs_dest *dest, IP_VS_WAIT_WHILE(atomic_read(&svc->usecnt) > 0); if (add) { - list_add(&dest->n_list, &svc->destinations); + list_add_rcu(&dest->n_list, &svc->destinations); svc->num_dests++; if (svc->scheduler->add_dest) svc->scheduler->add_dest(svc, dest); @@ -933,10 +932,10 @@ ip_vs_add_dest(struct ip_vs_service *svc, struct ip_vs_dest_user_kern *udest) ip_vs_addr_copy(svc->af, &daddr, &udest->addr); - /* - * Check if the dest already exists in the list - */ + /* We use function that requires RCU lock */ + rcu_read_lock(); dest = ip_vs_lookup_dest(svc, &daddr, dport); + rcu_read_unlock(); if (dest != NULL) { IP_VS_DBG(1, "%s(): dest already exists\n", __func__); @@ -997,10 +996,10 @@ ip_vs_edit_dest(struct ip_vs_service *svc, struct ip_vs_dest_user_kern *udest) ip_vs_addr_copy(svc->af, &daddr, &udest->addr); - /* - * Lookup the destination list - */ + /* We use function that requires RCU lock */ + rcu_read_lock(); dest = ip_vs_lookup_dest(svc, &daddr, dport); + rcu_read_unlock(); if (dest == NULL) { IP_VS_DBG(1, "%s(): dest doesn't exist\n", __func__); @@ -1069,7 +1068,7 @@ static void __ip_vs_unlink_dest(struct ip_vs_service *svc, /* * Remove it from the d-linked destination list. */ - list_del(&dest->n_list); + list_del_rcu(&dest->n_list); svc->num_dests--; if (svcupd && svc->scheduler->del_dest) @@ -1094,7 +1093,10 @@ ip_vs_del_dest(struct ip_vs_service *svc, struct ip_vs_dest_user_kern *udest) EnterFunction(2); + /* We use function that requires RCU lock */ + rcu_read_lock(); dest = ip_vs_lookup_dest(svc, &udest->addr, dport); + rcu_read_unlock(); if (dest == NULL) { IP_VS_DBG(1, "%s(): destination not found!\n", __func__); @@ -2104,7 +2106,7 @@ static int ip_vs_info_seq_show(struct seq_file *seq, void *v) else seq_putc(seq, '\n'); - list_for_each_entry(dest, &svc->destinations, n_list) { + list_for_each_entry_rcu(dest, &svc->destinations, n_list) { #ifdef CONFIG_IP_VS_IPV6 if (dest->af == AF_INET6) seq_printf(seq, diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c index 6cc3e52..9724174 100644 --- a/net/netfilter/ipvs/ip_vs_sync.c +++ b/net/netfilter/ipvs/ip_vs_sync.c @@ -858,23 +858,20 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param, flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK; cp->flags = flags; spin_unlock(&cp->lock); - if (!dest) { - dest = ip_vs_try_bind_dest(cp); - if (dest) - ip_vs_dest_put(dest); - } + if (!dest) + ip_vs_try_bind_dest(cp); } else { /* * Find the appropriate destination for the connection. * If it is not found the connection will remain unbound * but still handled. */ + rcu_read_lock(); dest = ip_vs_find_dest(net, type, daddr, dport, param->vaddr, param->vport, protocol, fwmark, flags); cp = ip_vs_conn_new(param, daddr, dport, flags, dest, fwmark); - if (dest) - ip_vs_dest_put(dest); + rcu_read_unlock(); if (!cp) { if (param->pe_data) kfree(param->pe_data);