[GIT PULL next-net] IPVS

[GIT PULL next-net] IPVS

[Simon Horman]

Hi Pablo,

please consider the following 5 changes for 3.4, they are all bug fixes.
I would also like these changes considered for stable.

Please note that there will be a conflict with the following when merged with
net-next:

	4a17fd5 sock: Introduce named constants for sk_reuse


The following changes since commit c3dc836d807a9b9855eefe535fdcbcf7cbb7a574:

  netfilter: bridge: optionally set indev to vlan (2012-04-24 01:22:44 +0200)

are available in the git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/horms/ipvs-next.git master

for you to fetch changes up to f0cb1dbac57864ed702da8ada6a00155fff0a13b:

  IPVS: ip_vs_proto.c: local functions should not be exposed globally (2012-05-02 10:12:37 +0900)

----------------------------------------------------------------
H Hartley Sweeten (2):
      IPVS: ip_vs_ftp.c: local functions should not be exposed globally
      IPVS: ip_vs_proto.c: local functions should not be exposed globally

Julian Anastasov (14):
      ipvs: timeout tables do not need GFP_ATOMIC allocation
      ipvs: LBLC scheduler does not need GFP_ATOMIC allocation on init
      ipvs: DH scheduler does not need GFP_ATOMIC allocation
      ipvs: WRR scheduler does not need GFP_ATOMIC allocation
      ipvs: LBLCR scheduler does not need GFP_ATOMIC allocation on init
      ipvs: SH scheduler does not need GFP_ATOMIC allocation
      ipvs: ignore IP_VS_CONN_F_NOOUTPUT in backup server
      ipvs: remove check for IP_VS_CONN_F_SYNC from ip_vs_bind_dest
      ipvs: fix ip_vs_try_bind_dest to rebind app and transmitter
      ipvs: always update some of the flags bits in backup
      ipvs: wakeup master thread
      ipvs: reduce sync rate with time thresholds
      ipvs: add support for sync threads
      ipvs: optimize the use of flags in ip_vs_bind_dest

Sasha Levin (1):
      netfilter: ipvs: use GFP_KERNEL allocation where possible

 include/linux/ip_vs.h            |    5 +
 include/net/ip_vs.h              |   87 ++++-
 net/netfilter/ipvs/ip_vs_conn.c  |   69 ++--
 net/netfilter/ipvs/ip_vs_core.c  |   30 +-
 net/netfilter/ipvs/ip_vs_ctl.c   |   70 +++-
 net/netfilter/ipvs/ip_vs_dh.c    |    2 +-
 net/netfilter/ipvs/ip_vs_ftp.c   |    2 +-
 net/netfilter/ipvs/ip_vs_lblc.c  |    2 +-
 net/netfilter/ipvs/ip_vs_lblcr.c |    2 +-
 net/netfilter/ipvs/ip_vs_proto.c |    6 +-
 net/netfilter/ipvs/ip_vs_sh.c    |    2 +-
 net/netfilter/ipvs/ip_vs_sync.c  |  662 ++++++++++++++++++++++++++------------
 net/netfilter/ipvs/ip_vs_wrr.c   |    2 +-
 13 files changed, 667 insertions(+), 274 deletions(-)

[PATCH 01/17] ipvs: timeout tables do not need GFP_ATOMIC allocation

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	They are called only on initialization.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_proto.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_proto.c b/net/netfilter/ipvs/ip_vs_proto.c
index 6eda11d..a981b7c 100644
--- a/net/netfilter/ipvs/ip_vs_proto.c
+++ b/net/netfilter/ipvs/ip_vs_proto.c
@@ -196,7 +196,7 @@ void ip_vs_protocol_timeout_change(struct netns_ipvs *ipvs, int flags)
 int *
 ip_vs_create_timeout_table(int *table, int size)
 {
-	return kmemdup(table, size, GFP_ATOMIC);
+	return kmemdup(table, size, GFP_KERNEL);
 }
 
 
-- 
1.7.9.5

[PATCH 02/17] ipvs: LBLC scheduler does not need GFP_ATOMIC allocation on init

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Schedulers are initialized and bound to services only
on commands.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_lblc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_lblc.c b/net/netfilter/ipvs/ip_vs_lblc.c
index 27c24f1..7ba1672 100644
--- a/net/netfilter/ipvs/ip_vs_lblc.c
+++ b/net/netfilter/ipvs/ip_vs_lblc.c
@@ -342,7 +342,7 @@ static int ip_vs_lblc_init_svc(struct ip_vs_service *svc)
 	/*
 	 *    Allocate the ip_vs_lblc_table for this service
 	 */
-	tbl = kmalloc(sizeof(*tbl), GFP_ATOMIC);
+	tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);
 	if (tbl == NULL)
 		return -ENOMEM;
 
-- 
1.7.9.5

[PATCH 03/17] ipvs: DH scheduler does not need GFP_ATOMIC allocation

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Schedulers are initialized and bound to services only
on commands.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_dh.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_dh.c b/net/netfilter/ipvs/ip_vs_dh.c
index 1a53a7a..8b7dca9 100644
--- a/net/netfilter/ipvs/ip_vs_dh.c
+++ b/net/netfilter/ipvs/ip_vs_dh.c
@@ -149,7 +149,7 @@ static int ip_vs_dh_init_svc(struct ip_vs_service *svc)
 
 	/* allocate the DH table for this service */
 	tbl = kmalloc(sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE,
-		      GFP_ATOMIC);
+		      GFP_KERNEL);
 	if (tbl == NULL)
 		return -ENOMEM;
 
-- 
1.7.9.5

[PATCH 04/17] ipvs: WRR scheduler does not need GFP_ATOMIC allocation

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Schedulers are initialized and bound to services only
on commands.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_wrr.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_wrr.c b/net/netfilter/ipvs/ip_vs_wrr.c
index fd0d4e0..231be7d 100644
--- a/net/netfilter/ipvs/ip_vs_wrr.c
+++ b/net/netfilter/ipvs/ip_vs_wrr.c
@@ -84,7 +84,7 @@ static int ip_vs_wrr_init_svc(struct ip_vs_service *svc)
 	/*
 	 *    Allocate the mark variable for WRR scheduling
 	 */
-	mark = kmalloc(sizeof(struct ip_vs_wrr_mark), GFP_ATOMIC);
+	mark = kmalloc(sizeof(struct ip_vs_wrr_mark), GFP_KERNEL);
 	if (mark == NULL)
 		return -ENOMEM;
 
-- 
1.7.9.5

[PATCH 05/17] ipvs: LBLCR scheduler does not need GFP_ATOMIC allocation on init

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Schedulers are initialized and bound to services only
on commands.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_lblcr.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_lblcr.c b/net/netfilter/ipvs/ip_vs_lblcr.c
index 7498756..00906ea 100644
--- a/net/netfilter/ipvs/ip_vs_lblcr.c
+++ b/net/netfilter/ipvs/ip_vs_lblcr.c
@@ -511,7 +511,7 @@ static int ip_vs_lblcr_init_svc(struct ip_vs_service *svc)
 	/*
 	 *    Allocate the ip_vs_lblcr_table for this service
 	 */
-	tbl = kmalloc(sizeof(*tbl), GFP_ATOMIC);
+	tbl = kmalloc(sizeof(*tbl), GFP_KERNEL);
 	if (tbl == NULL)
 		return -ENOMEM;
 
-- 
1.7.9.5

[PATCH 06/17] ipvs: SH scheduler does not need GFP_ATOMIC allocation

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

        Schedulers are initialized and bound to services only
on commands.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Hans Schillstrom <hans@schillstrom.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_sh.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_sh.c b/net/netfilter/ipvs/ip_vs_sh.c
index 91e97ee..0512652 100644
--- a/net/netfilter/ipvs/ip_vs_sh.c
+++ b/net/netfilter/ipvs/ip_vs_sh.c
@@ -162,7 +162,7 @@ static int ip_vs_sh_init_svc(struct ip_vs_service *svc)
 
 	/* allocate the SH table for this service */
 	tbl = kmalloc(sizeof(struct ip_vs_sh_bucket)*IP_VS_SH_TAB_SIZE,
-		      GFP_ATOMIC);
+		      GFP_KERNEL);
 	if (tbl == NULL)
 		return -ENOMEM;
 
-- 
1.7.9.5

[PATCH 07/17] netfilter: ipvs: use GFP_KERNEL allocation where possible

[Simon Horman]

From: Sasha Levin <levinsasha928@gmail.com>

Use GFP_KERNEL instead of GFP_ATOMIC when registering an ipvs protocol.

This is safe since it will always run from a process context.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Acked-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_proto.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_proto.c b/net/netfilter/ipvs/ip_vs_proto.c
index a981b7c..8726488 100644
--- a/net/netfilter/ipvs/ip_vs_proto.c
+++ b/net/netfilter/ipvs/ip_vs_proto.c
@@ -71,7 +71,7 @@ register_ip_vs_proto_netns(struct net *net, struct ip_vs_protocol *pp)
 	struct netns_ipvs *ipvs = net_ipvs(net);
 	unsigned int hash = IP_VS_PROTO_HASH(pp->protocol);
 	struct ip_vs_proto_data *pd =
-			kzalloc(sizeof(struct ip_vs_proto_data), GFP_ATOMIC);
+			kzalloc(sizeof(struct ip_vs_proto_data), GFP_KERNEL);
 
 	if (!pd)
 		return -ENOMEM;
-- 
1.7.9.5

[PATCH 08/17] ipvs: ignore IP_VS_CONN_F_NOOUTPUT in backup server

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	As IP_VS_CONN_F_NOOUTPUT is derived from the
forwarding method we should get it from conn_flags just
like we do it for IP_VS_CONN_F_FWD_MASK bits when binding
to real server.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_conn.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 4a09b78..f562e63 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -567,7 +567,7 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE))
 			conn_flags &= ~IP_VS_CONN_F_INACTIVE;
 		/* connections inherit forwarding method from dest */
-		cp->flags &= ~IP_VS_CONN_F_FWD_MASK;
+		cp->flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT);
 	}
 	cp->flags |= conn_flags;
 	cp->dest = dest;
-- 
1.7.9.5

[PATCH 09/17] ipvs: remove check for IP_VS_CONN_F_SYNC from ip_vs_bind_dest

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	As the IP_VS_CONN_F_INACTIVE bit is properly set
in cp->flags for all kind of connections we do not need to
add special checks for synced connections when updating
the activeconns/inactconns counters for first time. Now
logic will look just like in ip_vs_unbind_dest.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_conn.c |    9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index f562e63..7647f3b 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -585,11 +585,10 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 
 	/* Update the connection counters */
 	if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
-		/* It is a normal connection, so increase the inactive
-		   connection counter because it is in TCP SYNRECV
-		   state (inactive) or other protocol inacive state */
-		if ((cp->flags & IP_VS_CONN_F_SYNC) &&
-		    (!(cp->flags & IP_VS_CONN_F_INACTIVE)))
+		/* It is a normal connection, so modify the counters
+		 * according to the flags, later the protocol can
+		 * update them on state change */
+		if (!(cp->flags & IP_VS_CONN_F_INACTIVE))
 			atomic_inc(&dest->activeconns);
 		else
 			atomic_inc(&dest->inactconns);
-- 
1.7.9.5

[PATCH 10/17] ipvs: fix ip_vs_try_bind_dest to rebind app and transmitter

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Initially, when the synced connection is created we
use the forwarding method provided by master but once we
bind to destination it can be changed. As result, we must
update the application and the transmitter.

	As ip_vs_try_bind_dest is called always for connections
that require dest binding, there is no need to validate the
cp and dest pointers.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_conn.c |   33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 7647f3b..9d237d7 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -612,14 +612,33 @@ struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
 {
 	struct ip_vs_dest *dest;
 
-	if ((cp) && (!cp->dest)) {
-		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);
+	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);
+	if (dest) {
+		struct ip_vs_proto_data *pd;
+
+		/* Applications work depending on the forwarding method
+		 * but better to reassign them always when binding dest */
+		if (cp->app)
+			ip_vs_unbind_app(cp);
+
 		ip_vs_bind_dest(cp, dest);
-		return dest;
-	} else
-		return NULL;
+
+		/* Update its packet transmitter */
+		cp->packet_xmit = NULL;
+#ifdef CONFIG_IP_VS_IPV6
+		if (cp->af == AF_INET6)
+			ip_vs_bind_xmit_v6(cp);
+		else
+#endif
+			ip_vs_bind_xmit(cp);
+
+		pd = ip_vs_proto_data_get(ip_vs_conn_net(cp), cp->protocol);
+		if (pd && atomic_read(&pd->appcnt))
+			ip_vs_bind_app(cp, pd->pp);
+	}
+	return dest;
 }
 
 
-- 
1.7.9.5

[PATCH 11/17] ipvs: always update some of the flags bits in backup

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	As the goal is to mirror the inactconns/activeconns
counters in the backup server, make sure the cp->flags are
updated even if cp is still not bound to dest. If cp->flags
are not updated ip_vs_bind_dest will rely only on the initial
flags when updating the counters. To avoid mistakes and
complicated checks for protocol state rely only on the
IP_VS_CONN_F_INACTIVE bit when updating the counters.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Tested-by: Aleksey Chudov <aleksey.chudov@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 include/linux/ip_vs.h           |    5 +++
 net/netfilter/ipvs/ip_vs_sync.c |   65 ++++++++++++++-------------------------
 2 files changed, 28 insertions(+), 42 deletions(-)

diff --git a/include/linux/ip_vs.h b/include/linux/ip_vs.h
index be0ef3d..8a2d438 100644
--- a/include/linux/ip_vs.h
+++ b/include/linux/ip_vs.h
@@ -89,6 +89,7 @@
 #define IP_VS_CONN_F_TEMPLATE	0x1000		/* template, not connection */
 #define IP_VS_CONN_F_ONE_PACKET	0x2000		/* forward only one packet */
 
+/* Initial bits allowed in backup server */
 #define IP_VS_CONN_F_BACKUP_MASK (IP_VS_CONN_F_FWD_MASK | \
 				  IP_VS_CONN_F_NOOUTPUT | \
 				  IP_VS_CONN_F_INACTIVE | \
@@ -97,6 +98,10 @@
 				  IP_VS_CONN_F_TEMPLATE \
 				 )
 
+/* Bits allowed to update in backup server */
+#define IP_VS_CONN_F_BACKUP_UPD_MASK (IP_VS_CONN_F_INACTIVE | \
+				      IP_VS_CONN_F_SEQ_MASK)
+
 /* Flags that are not sent to backup server start from bit 16 */
 #define IP_VS_CONN_F_NFCT	(1 << 16)	/* use netfilter conntrack */
 
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index f4e0b6c..eeed767 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -731,9 +731,30 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 	else
 		cp = ip_vs_ct_in_get(param);
 
-	if (cp && param->pe_data) 	/* Free pe_data */
+	if (cp) {
+		/* Free pe_data */
 		kfree(param->pe_data);
-	if (!cp) {
+
+		dest = cp->dest;
+		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
+		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
+			if (flags & IP_VS_CONN_F_INACTIVE) {
+				atomic_dec(&dest->activeconns);
+				atomic_inc(&dest->inactconns);
+			} else {
+				atomic_inc(&dest->activeconns);
+				atomic_dec(&dest->inactconns);
+			}
+		}
+		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
+		flags |= cp->flags & ~IP_VS_CONN_F_BACKUP_UPD_MASK;
+		cp->flags = flags;
+		if (!dest) {
+			dest = ip_vs_try_bind_dest(cp);
+			if (dest)
+				atomic_dec(&dest->refcnt);
+		}
+	} else {
 		/*
 		 * Find the appropriate destination for the connection.
 		 * If it is not found the connection will remain unbound
@@ -742,18 +763,6 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 		dest = ip_vs_find_dest(net, type, daddr, dport, param->vaddr,
 				       param->vport, protocol, fwmark, flags);
 
-		/*  Set the approprite ativity flag */
-		if (protocol == IPPROTO_TCP) {
-			if (state != IP_VS_TCP_S_ESTABLISHED)
-				flags |= IP_VS_CONN_F_INACTIVE;
-			else
-				flags &= ~IP_VS_CONN_F_INACTIVE;
-		} else if (protocol == IPPROTO_SCTP) {
-			if (state != IP_VS_SCTP_S_ESTABLISHED)
-				flags |= IP_VS_CONN_F_INACTIVE;
-			else
-				flags &= ~IP_VS_CONN_F_INACTIVE;
-		}
 		cp = ip_vs_conn_new(param, daddr, dport, flags, dest, fwmark);
 		if (dest)
 			atomic_dec(&dest->refcnt);
@@ -763,34 +772,6 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 			IP_VS_DBG(2, "BACKUP, add new conn. failed\n");
 			return;
 		}
-	} else if (!cp->dest) {
-		dest = ip_vs_try_bind_dest(cp);
-		if (dest)
-			atomic_dec(&dest->refcnt);
-	} else if ((cp->dest) && (cp->protocol == IPPROTO_TCP) &&
-		(cp->state != state)) {
-		/* update active/inactive flag for the connection */
-		dest = cp->dest;
-		if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
-			(state != IP_VS_TCP_S_ESTABLISHED)) {
-			atomic_dec(&dest->activeconns);
-			atomic_inc(&dest->inactconns);
-			cp->flags |= IP_VS_CONN_F_INACTIVE;
-		} else if ((cp->flags & IP_VS_CONN_F_INACTIVE) &&
-			(state == IP_VS_TCP_S_ESTABLISHED)) {
-			atomic_inc(&dest->activeconns);
-			atomic_dec(&dest->inactconns);
-			cp->flags &= ~IP_VS_CONN_F_INACTIVE;
-		}
-	} else if ((cp->dest) && (cp->protocol == IPPROTO_SCTP) &&
-		(cp->state != state)) {
-		dest = cp->dest;
-		if (!(cp->flags & IP_VS_CONN_F_INACTIVE) &&
-		(state != IP_VS_SCTP_S_ESTABLISHED)) {
-			atomic_dec(&dest->activeconns);
-			atomic_inc(&dest->inactconns);
-			cp->flags &= ~IP_VS_CONN_F_INACTIVE;
-		}
 	}
 
 	if (opt)
-- 
1.7.9.5

[PATCH 12/17] ipvs: wakeup master thread

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	High rate of sync messages in master can lead to
overflowing the socket buffer and dropping the messages.
Fixed sleep of 1 second without wakeup events is not suitable
for loaded masters,

	Use delayed_work to schedule sending for queued messages
and limit the delay to IPVS_SYNC_SEND_DELAY (20ms). This will
reduce the rate of wakeups but to avoid sending long bursts we
wakeup the master thread after IPVS_SYNC_WAKEUP_RATE (8) messages.

	Add hard limit for the queued messages before sending
by using "sync_qlen_max" sysctl var. It defaults to 1/32 of
the memory pages but actually represents number of messages.
It will protect us from allocating large parts of memory
when the sending rate is lower than the queuing rate.

	As suggested by Pablo, add new sysctl var
"sync_sock_size" to configure the SNDBUF (master) or
RCVBUF (slave) socket limit. Default value is 0 (preserve
system defaults).

	Change the master thread to detect and block on
SNDBUF overflow, so that we do not drop messages when
the socket limit is low but the sync_qlen_max limit is
not reached. On ENOBUFS or other errors just drop the
messages.

	Change master thread to enter TASK_INTERRUPTIBLE
state early, so that we do not miss wakeups due to messages or
kthread_should_stop event.

Thanks to Pablo Neira Ayuso for his valuable feedback!

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 include/net/ip_vs.h             |   29 ++++++++
 net/netfilter/ipvs/ip_vs_ctl.c  |   16 +++++
 net/netfilter/ipvs/ip_vs_sync.c |  149 ++++++++++++++++++++++++++++++---------
 3 files changed, 162 insertions(+), 32 deletions(-)

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index a903a82..8721a78 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -870,6 +870,8 @@ struct netns_ipvs {
 #endif
 	int			sysctl_snat_reroute;
 	int			sysctl_sync_ver;
+	int			sysctl_sync_qlen_max;
+	int			sysctl_sync_sock_size;
 	int			sysctl_cache_bypass;
 	int			sysctl_expire_nodest_conn;
 	int			sysctl_expire_quiescent_template;
@@ -890,6 +892,9 @@ struct netns_ipvs {
 	struct timer_list	est_timer;	/* Estimation timer */
 	/* ip_vs_sync */
 	struct list_head	sync_queue;
+	int			sync_queue_len;
+	unsigned int		sync_queue_delay;
+	struct delayed_work	master_wakeup_work;
 	spinlock_t		sync_lock;
 	struct ip_vs_sync_buff  *sync_buff;
 	spinlock_t		sync_buff_lock;
@@ -912,6 +917,10 @@ struct netns_ipvs {
 #define DEFAULT_SYNC_THRESHOLD	3
 #define DEFAULT_SYNC_PERIOD	50
 #define DEFAULT_SYNC_VER	1
+#define IPVS_SYNC_WAKEUP_RATE	8
+#define IPVS_SYNC_QLEN_MAX	(IPVS_SYNC_WAKEUP_RATE * 4)
+#define IPVS_SYNC_SEND_DELAY	(HZ / 50)
+#define IPVS_SYNC_CHECK_PERIOD	HZ
 
 #ifdef CONFIG_SYSCTL
 
@@ -930,6 +939,16 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
 	return ipvs->sysctl_sync_ver;
 }
 
+static inline int sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
+{
+	return ipvs->sysctl_sync_qlen_max;
+}
+
+static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
+{
+	return ipvs->sysctl_sync_sock_size;
+}
+
 #else
 
 static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
@@ -947,6 +966,16 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
 	return DEFAULT_SYNC_VER;
 }
 
+static inline int sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
+{
+	return IPVS_SYNC_QLEN_MAX;
+}
+
+static inline int sysctl_sync_sock_size(struct netns_ipvs *ipvs)
+{
+	return 0;
+}
+
 #endif
 
 /*
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index b8d0df7..854e9a6 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -1718,6 +1718,18 @@ static struct ctl_table vs_vars[] = {
 		.proc_handler	= &proc_do_sync_mode,
 	},
 	{
+		.procname	= "sync_qlen_max",
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{
+		.procname	= "sync_sock_size",
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec,
+	},
+	{
 		.procname	= "cache_bypass",
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
@@ -3662,6 +3674,10 @@ int __net_init ip_vs_control_net_init_sysctl(struct net *net)
 	tbl[idx++].data = &ipvs->sysctl_snat_reroute;
 	ipvs->sysctl_sync_ver = 1;
 	tbl[idx++].data = &ipvs->sysctl_sync_ver;
+	ipvs->sysctl_sync_qlen_max = nr_free_buffer_pages() / 32;
+	tbl[idx++].data = &ipvs->sysctl_sync_qlen_max;
+	ipvs->sysctl_sync_sock_size = 0;
+	tbl[idx++].data = &ipvs->sysctl_sync_sock_size;
 	tbl[idx++].data = &ipvs->sysctl_cache_bypass;
 	tbl[idx++].data = &ipvs->sysctl_expire_nodest_conn;
 	tbl[idx++].data = &ipvs->sysctl_expire_quiescent_template;
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index eeed767..eafc1d2 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -307,11 +307,15 @@ static inline struct ip_vs_sync_buff *sb_dequeue(struct netns_ipvs *ipvs)
 	spin_lock_bh(&ipvs->sync_lock);
 	if (list_empty(&ipvs->sync_queue)) {
 		sb = NULL;
+		__set_current_state(TASK_INTERRUPTIBLE);
 	} else {
 		sb = list_entry(ipvs->sync_queue.next,
 				struct ip_vs_sync_buff,
 				list);
 		list_del(&sb->list);
+		ipvs->sync_queue_len--;
+		if (!ipvs->sync_queue_len)
+			ipvs->sync_queue_delay = 0;
 	}
 	spin_unlock_bh(&ipvs->sync_lock);
 
@@ -358,9 +362,16 @@ static inline void sb_queue_tail(struct netns_ipvs *ipvs)
 	struct ip_vs_sync_buff *sb = ipvs->sync_buff;
 
 	spin_lock(&ipvs->sync_lock);
-	if (ipvs->sync_state & IP_VS_STATE_MASTER)
+	if (ipvs->sync_state & IP_VS_STATE_MASTER &&
+	    ipvs->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
+		if (!ipvs->sync_queue_len)
+			schedule_delayed_work(&ipvs->master_wakeup_work,
+					      max(IPVS_SYNC_SEND_DELAY, 1));
+		ipvs->sync_queue_len++;
 		list_add_tail(&sb->list, &ipvs->sync_queue);
-	else
+		if ((++ipvs->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE)
+			wake_up_process(ipvs->master_thread);
+	} else
 		ip_vs_sync_buff_release(sb);
 	spin_unlock(&ipvs->sync_lock);
 }
@@ -379,6 +390,7 @@ get_curr_sync_buff(struct netns_ipvs *ipvs, unsigned long time)
 	    time_after_eq(jiffies - ipvs->sync_buff->firstuse, time)) {
 		sb = ipvs->sync_buff;
 		ipvs->sync_buff = NULL;
+		__set_current_state(TASK_RUNNING);
 	} else
 		sb = NULL;
 	spin_unlock_bh(&ipvs->sync_buff_lock);
@@ -392,26 +404,23 @@ get_curr_sync_buff(struct netns_ipvs *ipvs, unsigned long time)
 void ip_vs_sync_switch_mode(struct net *net, int mode)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
+	struct ip_vs_sync_buff *sb;
 
+	spin_lock_bh(&ipvs->sync_buff_lock);
 	if (!(ipvs->sync_state & IP_VS_STATE_MASTER))
-		return;
-	if (mode == sysctl_sync_ver(ipvs) || !ipvs->sync_buff)
-		return;
+		goto unlock;
+	sb = ipvs->sync_buff;
+	if (mode == sysctl_sync_ver(ipvs) || !sb)
+		goto unlock;
 
-	spin_lock_bh(&ipvs->sync_buff_lock);
 	/* Buffer empty ? then let buf_create do the job  */
-	if (ipvs->sync_buff->mesg->size <=  sizeof(struct ip_vs_sync_mesg)) {
-		kfree(ipvs->sync_buff);
+	if (sb->mesg->size <= sizeof(struct ip_vs_sync_mesg)) {
+		ip_vs_sync_buff_release(sb);
 		ipvs->sync_buff = NULL;
-	} else {
-		spin_lock_bh(&ipvs->sync_lock);
-		if (ipvs->sync_state & IP_VS_STATE_MASTER)
-			list_add_tail(&ipvs->sync_buff->list,
-				      &ipvs->sync_queue);
-		else
-			ip_vs_sync_buff_release(ipvs->sync_buff);
-		spin_unlock_bh(&ipvs->sync_lock);
-	}
+	} else
+		sb_queue_tail(ipvs);
+
+unlock:
 	spin_unlock_bh(&ipvs->sync_buff_lock);
 }
 
@@ -1130,6 +1139,28 @@ static void ip_vs_process_message(struct net *net, __u8 *buffer,
 
 
 /*
+ *      Setup sndbuf (mode=1) or rcvbuf (mode=0)
+ */
+static void set_sock_size(struct sock *sk, int mode, int val)
+{
+	/* setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &val, sizeof(val)); */
+	/* setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &val, sizeof(val)); */
+	lock_sock(sk);
+	if (mode) {
+		val = clamp_t(int, val, (SOCK_MIN_SNDBUF + 1) / 2,
+			      sysctl_wmem_max);
+		sk->sk_sndbuf = val * 2;
+		sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
+	} else {
+		val = clamp_t(int, val, (SOCK_MIN_RCVBUF + 1) / 2,
+			      sysctl_rmem_max);
+		sk->sk_rcvbuf = val * 2;
+		sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
+	}
+	release_sock(sk);
+}
+
+/*
  *      Setup loopback of outgoing multicasts on a sending socket
  */
 static void set_mcast_loop(struct sock *sk, u_char loop)
@@ -1305,6 +1336,9 @@ static struct socket *make_send_sock(struct net *net)
 
 	set_mcast_loop(sock->sk, 0);
 	set_mcast_ttl(sock->sk, 1);
+	result = sysctl_sync_sock_size(ipvs);
+	if (result > 0)
+		set_sock_size(sock->sk, 1, result);
 
 	result = bind_mcastif_addr(sock, ipvs->master_mcast_ifn);
 	if (result < 0) {
@@ -1350,6 +1384,9 @@ static struct socket *make_receive_sock(struct net *net)
 	sk_change_net(sock->sk, net);
 	/* it is equivalent to the REUSEADDR option in user-space */
 	sock->sk->sk_reuse = 1;
+	result = sysctl_sync_sock_size(ipvs);
+	if (result > 0)
+		set_sock_size(sock->sk, 0, result);
 
 	result = sock->ops->bind(sock, (struct sockaddr *) &mcast_addr,
 			sizeof(struct sockaddr));
@@ -1392,18 +1429,22 @@ ip_vs_send_async(struct socket *sock, const char *buffer, const size_t length)
 	return len;
 }
 
-static void
+static int
 ip_vs_send_sync_msg(struct socket *sock, struct ip_vs_sync_mesg *msg)
 {
 	int msize;
+	int ret;
 
 	msize = msg->size;
 
 	/* Put size in network byte order */
 	msg->size = htons(msg->size);
 
-	if (ip_vs_send_async(sock, (char *)msg, msize) != msize)
-		pr_err("ip_vs_send_async error\n");
+	ret = ip_vs_send_async(sock, (char *)msg, msize);
+	if (ret >= 0 || ret == -EAGAIN)
+		return ret;
+	pr_err("ip_vs_send_async error %d\n", ret);
+	return 0;
 }
 
 static int
@@ -1428,36 +1469,75 @@ ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
 	return len;
 }
 
+/* Wakeup the master thread for sending */
+static void master_wakeup_work_handler(struct work_struct *work)
+{
+	struct netns_ipvs *ipvs = container_of(work, struct netns_ipvs,
+					       master_wakeup_work.work);
+
+	spin_lock_bh(&ipvs->sync_lock);
+	if (ipvs->sync_queue_len &&
+	    ipvs->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
+		ipvs->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
+		wake_up_process(ipvs->master_thread);
+	}
+	spin_unlock_bh(&ipvs->sync_lock);
+}
+
+/* Get next buffer to send */
+static inline struct ip_vs_sync_buff *
+next_sync_buff(struct netns_ipvs *ipvs)
+{
+	struct ip_vs_sync_buff *sb;
+
+	sb = sb_dequeue(ipvs);
+	if (sb)
+		return sb;
+	/* Do not delay entries in buffer for more than 2 seconds */
+	return get_curr_sync_buff(ipvs, 2 * HZ);
+}
 
 static int sync_thread_master(void *data)
 {
 	struct ip_vs_sync_thread_data *tinfo = data;
 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
+	struct sock *sk = tinfo->sock->sk;
 	struct ip_vs_sync_buff *sb;
 
 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
 		"syncid = %d\n",
 		ipvs->master_mcast_ifn, ipvs->master_syncid);
 
-	while (!kthread_should_stop()) {
-		while ((sb = sb_dequeue(ipvs))) {
-			ip_vs_send_sync_msg(tinfo->sock, sb->mesg);
-			ip_vs_sync_buff_release(sb);
+	for (;;) {
+		sb = next_sync_buff(ipvs);
+		if (unlikely(kthread_should_stop()))
+			break;
+		if (!sb) {
+			schedule_timeout(IPVS_SYNC_CHECK_PERIOD);
+			continue;
 		}
-
-		/* check if entries stay in ipvs->sync_buff for 2 seconds */
-		sb = get_curr_sync_buff(ipvs, 2 * HZ);
-		if (sb) {
-			ip_vs_send_sync_msg(tinfo->sock, sb->mesg);
-			ip_vs_sync_buff_release(sb);
+		while (ip_vs_send_sync_msg(tinfo->sock, sb->mesg) < 0) {
+			int ret = 0;
+
+			__wait_event_interruptible(*sk_sleep(sk),
+						   sock_writeable(sk) ||
+						   kthread_should_stop(),
+						   ret);
+			if (unlikely(kthread_should_stop()))
+				goto done;
 		}
-
-		schedule_timeout_interruptible(HZ);
+		ip_vs_sync_buff_release(sb);
 	}
 
+done:
+	__set_current_state(TASK_RUNNING);
+	if (sb)
+		ip_vs_sync_buff_release(sb);
+
 	/* clean up the sync_buff queue */
 	while ((sb = sb_dequeue(ipvs)))
 		ip_vs_sync_buff_release(sb);
+	__set_current_state(TASK_RUNNING);
 
 	/* clean up the current sync_buff */
 	sb = get_curr_sync_buff(ipvs, 0);
@@ -1538,6 +1618,10 @@ int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
 		realtask = &ipvs->master_thread;
 		name = "ipvs_master:%d";
 		threadfn = sync_thread_master;
+		ipvs->sync_queue_len = 0;
+		ipvs->sync_queue_delay = 0;
+		INIT_DELAYED_WORK(&ipvs->master_wakeup_work,
+				  master_wakeup_work_handler);
 		sock = make_send_sock(net);
 	} else if (state == IP_VS_STATE_BACKUP) {
 		if (ipvs->backup_thread)
@@ -1623,6 +1707,7 @@ int stop_sync_thread(struct net *net, int state)
 		spin_lock_bh(&ipvs->sync_lock);
 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
 		spin_unlock_bh(&ipvs->sync_lock);
+		cancel_delayed_work_sync(&ipvs->master_wakeup_work);
 		retc = kthread_stop(ipvs->master_thread);
 		ipvs->master_thread = NULL;
 	} else if (state == IP_VS_STATE_BACKUP) {
-- 
1.7.9.5

[PATCH 13/17] ipvs: reduce sync rate with time thresholds

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Add two new sysctl vars to control the sync rate with the
main idea to reduce the rate for connection templates because
currently it depends on the packet rate for controlled connections.
This mechanism should be useful also for normal connections
with high traffic.

sync_refresh_period: in seconds, difference in reported connection
	timer that triggers new sync message. It can be used to
	avoid sync messages for the specified period (or half of
	the connection timeout if it is lower) if connection state
	is not changed from last sync.

sync_retries: integer, 0..3, defines sync retries with period of
	sync_refresh_period/8. Useful to protect against loss of
	sync messages.

	Allow sysctl_sync_threshold to be used with
sysctl_sync_period=0, so that only single sync message is sent
if sync_refresh_period is also 0.

	Add new field "sync_endtime" in connection structure to
hold the reported time when connection expires. The 2 lowest
bits will represent the retry count.

	As the sysctl_sync_period now can be 0 use ACCESS_ONCE to
avoid division by zero.

	Special thanks to Aleksey Chudov for being patient with me,
for his extensive reports and helping in all tests.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Tested-by: Aleksey Chudov <aleksey.chudov@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 include/net/ip_vs.h             |   30 +++++++++-
 net/netfilter/ipvs/ip_vs_conn.c |    7 ++-
 net/netfilter/ipvs/ip_vs_core.c |   30 +---------
 net/netfilter/ipvs/ip_vs_ctl.c  |   25 +++++++-
 net/netfilter/ipvs/ip_vs_sync.c |  121 +++++++++++++++++++++++++++++++++------
 5 files changed, 165 insertions(+), 48 deletions(-)

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index 8721a78..941df45 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -505,6 +505,7 @@ struct ip_vs_conn {
 						 * state transition triggerd
 						 * synchronization
 						 */
+	unsigned long		sync_endtime;	/* jiffies + sent_retries */
 
 	/* Control members */
 	struct ip_vs_conn       *control;       /* Master control connection */
@@ -876,6 +877,8 @@ struct netns_ipvs {
 	int			sysctl_expire_nodest_conn;
 	int			sysctl_expire_quiescent_template;
 	int			sysctl_sync_threshold[2];
+	unsigned int		sysctl_sync_refresh_period;
+	int			sysctl_sync_retries;
 	int			sysctl_nat_icmp_send;
 
 	/* ip_vs_lblc */
@@ -917,10 +920,13 @@ struct netns_ipvs {
 #define DEFAULT_SYNC_THRESHOLD	3
 #define DEFAULT_SYNC_PERIOD	50
 #define DEFAULT_SYNC_VER	1
+#define DEFAULT_SYNC_REFRESH_PERIOD	(0U * HZ)
+#define DEFAULT_SYNC_RETRIES		0
 #define IPVS_SYNC_WAKEUP_RATE	8
 #define IPVS_SYNC_QLEN_MAX	(IPVS_SYNC_WAKEUP_RATE * 4)
 #define IPVS_SYNC_SEND_DELAY	(HZ / 50)
 #define IPVS_SYNC_CHECK_PERIOD	HZ
+#define IPVS_SYNC_FLUSH_TIME	(HZ * 2)
 
 #ifdef CONFIG_SYSCTL
 
@@ -931,7 +937,17 @@ static inline int sysctl_sync_threshold(struct netns_ipvs *ipvs)
 
 static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
 {
-	return ipvs->sysctl_sync_threshold[1];
+	return ACCESS_ONCE(ipvs->sysctl_sync_threshold[1]);
+}
+
+static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
+{
+	return ACCESS_ONCE(ipvs->sysctl_sync_refresh_period);
+}
+
+static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
+{
+	return ipvs->sysctl_sync_retries;
 }
 
 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
@@ -961,6 +977,16 @@ static inline int sysctl_sync_period(struct netns_ipvs *ipvs)
 	return DEFAULT_SYNC_PERIOD;
 }
 
+static inline unsigned int sysctl_sync_refresh_period(struct netns_ipvs *ipvs)
+{
+	return DEFAULT_SYNC_REFRESH_PERIOD;
+}
+
+static inline int sysctl_sync_retries(struct netns_ipvs *ipvs)
+{
+	return DEFAULT_SYNC_RETRIES & 3;
+}
+
 static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
 {
 	return DEFAULT_SYNC_VER;
@@ -1248,7 +1274,7 @@ extern struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp);
 extern int start_sync_thread(struct net *net, int state, char *mcast_ifn,
 			     __u8 syncid);
 extern int stop_sync_thread(struct net *net, int state);
-extern void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp);
+extern void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts);
 
 
 /*
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 9d237d7..46260fb 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -761,7 +761,8 @@ int ip_vs_check_template(struct ip_vs_conn *ct)
 static void ip_vs_conn_expire(unsigned long data)
 {
 	struct ip_vs_conn *cp = (struct ip_vs_conn *)data;
-	struct netns_ipvs *ipvs = net_ipvs(ip_vs_conn_net(cp));
+	struct net *net = ip_vs_conn_net(cp);
+	struct netns_ipvs *ipvs = net_ipvs(net);
 
 	cp->timeout = 60*HZ;
 
@@ -826,6 +827,9 @@ static void ip_vs_conn_expire(unsigned long data)
 		  atomic_read(&cp->refcnt)-1,
 		  atomic_read(&cp->n_control));
 
+	if (ipvs->sync_state & IP_VS_STATE_MASTER)
+		ip_vs_sync_conn(net, cp, sysctl_sync_threshold(ipvs));
+
 	ip_vs_conn_put(cp);
 }
 
@@ -899,6 +903,7 @@ ip_vs_conn_new(const struct ip_vs_conn_param *p,
 	/* Set its state and timeout */
 	cp->state = 0;
 	cp->timeout = 3*HZ;
+	cp->sync_endtime = jiffies & ~3UL;
 
 	/* Bind its packet transmitter */
 #ifdef CONFIG_IP_VS_IPV6
diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
index b5a5c73..7ce5819 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1613,34 +1613,8 @@ ip_vs_in(unsigned int hooknum, struct sk_buff *skb, int af)
 	else
 		pkts = atomic_add_return(1, &cp->in_pkts);
 
-	if ((ipvs->sync_state & IP_VS_STATE_MASTER) &&
-	    cp->protocol == IPPROTO_SCTP) {
-		if ((cp->state == IP_VS_SCTP_S_ESTABLISHED &&
-			(pkts % sysctl_sync_period(ipvs)
-			 == sysctl_sync_threshold(ipvs))) ||
-				(cp->old_state != cp->state &&
-				 ((cp->state == IP_VS_SCTP_S_CLOSED) ||
-				  (cp->state == IP_VS_SCTP_S_SHUT_ACK_CLI) ||
-				  (cp->state == IP_VS_SCTP_S_SHUT_ACK_SER)))) {
-			ip_vs_sync_conn(net, cp);
-			goto out;
-		}
-	}
-
-	/* Keep this block last: TCP and others with pp->num_states <= 1 */
-	else if ((ipvs->sync_state & IP_VS_STATE_MASTER) &&
-	    (((cp->protocol != IPPROTO_TCP ||
-	       cp->state == IP_VS_TCP_S_ESTABLISHED) &&
-	      (pkts % sysctl_sync_period(ipvs)
-	       == sysctl_sync_threshold(ipvs))) ||
-	     ((cp->protocol == IPPROTO_TCP) && (cp->old_state != cp->state) &&
-	      ((cp->state == IP_VS_TCP_S_FIN_WAIT) ||
-	       (cp->state == IP_VS_TCP_S_CLOSE) ||
-	       (cp->state == IP_VS_TCP_S_CLOSE_WAIT) ||
-	       (cp->state == IP_VS_TCP_S_TIME_WAIT)))))
-		ip_vs_sync_conn(net, cp);
-out:
-	cp->old_state = cp->state;
+	if (ipvs->sync_state & IP_VS_STATE_MASTER)
+		ip_vs_sync_conn(net, cp, pkts);
 
 	ip_vs_conn_put(cp);
 	return ret;
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 854e9a6..83bdbbc 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -1599,6 +1599,10 @@ static int ip_vs_zero_all(struct net *net)
 }
 
 #ifdef CONFIG_SYSCTL
+
+static int zero;
+static int three = 3;
+
 static int
 proc_do_defense_mode(ctl_table *table, int write,
 		     void __user *buffer, size_t *lenp, loff_t *ppos)
@@ -1632,7 +1636,8 @@ proc_do_sync_threshold(ctl_table *table, int write,
 	memcpy(val, valp, sizeof(val));
 
 	rc = proc_dointvec(table, write, buffer, lenp, ppos);
-	if (write && (valp[0] < 0 || valp[1] < 0 || valp[0] >= valp[1])) {
+	if (write && (valp[0] < 0 || valp[1] < 0 ||
+	    (valp[0] >= valp[1] && valp[1]))) {
 		/* Restore the correct value */
 		memcpy(valp, val, sizeof(val));
 	}
@@ -1755,6 +1760,20 @@ static struct ctl_table vs_vars[] = {
 		.proc_handler	= proc_do_sync_threshold,
 	},
 	{
+		.procname	= "sync_refresh_period",
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{
+		.procname	= "sync_retries",
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &three,
+	},
+	{
 		.procname	= "nat_icmp_send",
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
@@ -3685,6 +3704,10 @@ int __net_init ip_vs_control_net_init_sysctl(struct net *net)
 	ipvs->sysctl_sync_threshold[1] = DEFAULT_SYNC_PERIOD;
 	tbl[idx].data = &ipvs->sysctl_sync_threshold;
 	tbl[idx++].maxlen = sizeof(ipvs->sysctl_sync_threshold);
+	ipvs->sysctl_sync_refresh_period = DEFAULT_SYNC_REFRESH_PERIOD;
+	tbl[idx++].data = &ipvs->sysctl_sync_refresh_period;
+	ipvs->sysctl_sync_retries = clamp_t(int, DEFAULT_SYNC_RETRIES, 0, 3);
+	tbl[idx++].data = &ipvs->sysctl_sync_retries;
 	tbl[idx++].data = &ipvs->sysctl_nat_icmp_send;
 
 
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index eafc1d2..4aa9290 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -451,11 +451,94 @@ ip_vs_sync_buff_create_v0(struct netns_ipvs *ipvs)
 	return sb;
 }
 
+/* Check if conn should be synced.
+ * pkts: conn packets, use sysctl_sync_threshold to avoid packet check
+ * - (1) sync_refresh_period: reduce sync rate. Additionally, retry
+ *	sync_retries times with period of sync_refresh_period/8
+ * - (2) if both sync_refresh_period and sync_period are 0 send sync only
+ *	for state changes or only once when pkts matches sync_threshold
+ * - (3) templates: rate can be reduced only with sync_refresh_period or
+ *	with (2)
+ */
+static int ip_vs_sync_conn_needed(struct netns_ipvs *ipvs,
+				  struct ip_vs_conn *cp, int pkts)
+{
+	unsigned long orig = ACCESS_ONCE(cp->sync_endtime);
+	unsigned long now = jiffies;
+	unsigned long n = (now + cp->timeout) & ~3UL;
+	unsigned int sync_refresh_period;
+	int sync_period;
+	int force;
+
+	/* Check if we sync in current state */
+	if (unlikely(cp->flags & IP_VS_CONN_F_TEMPLATE))
+		force = 0;
+	else if (likely(cp->protocol == IPPROTO_TCP)) {
+		if (!((1 << cp->state) &
+		      ((1 << IP_VS_TCP_S_ESTABLISHED) |
+		       (1 << IP_VS_TCP_S_FIN_WAIT) |
+		       (1 << IP_VS_TCP_S_CLOSE) |
+		       (1 << IP_VS_TCP_S_CLOSE_WAIT) |
+		       (1 << IP_VS_TCP_S_TIME_WAIT))))
+			return 0;
+		force = cp->state != cp->old_state;
+		if (force && cp->state != IP_VS_TCP_S_ESTABLISHED)
+			goto set;
+	} else if (unlikely(cp->protocol == IPPROTO_SCTP)) {
+		if (!((1 << cp->state) &
+		      ((1 << IP_VS_SCTP_S_ESTABLISHED) |
+		       (1 << IP_VS_SCTP_S_CLOSED) |
+		       (1 << IP_VS_SCTP_S_SHUT_ACK_CLI) |
+		       (1 << IP_VS_SCTP_S_SHUT_ACK_SER))))
+			return 0;
+		force = cp->state != cp->old_state;
+		if (force && cp->state != IP_VS_SCTP_S_ESTABLISHED)
+			goto set;
+	} else {
+		/* UDP or another protocol with single state */
+		force = 0;
+	}
+
+	sync_refresh_period = sysctl_sync_refresh_period(ipvs);
+	if (sync_refresh_period > 0) {
+		long diff = n - orig;
+		long min_diff = max(cp->timeout >> 1, 10UL * HZ);
+
+		/* Avoid sync if difference is below sync_refresh_period
+		 * and below the half timeout.
+		 */
+		if (abs(diff) < min_t(long, sync_refresh_period, min_diff)) {
+			int retries = orig & 3;
+
+			if (retries >= sysctl_sync_retries(ipvs))
+				return 0;
+			if (time_before(now, orig - cp->timeout +
+					(sync_refresh_period >> 3)))
+				return 0;
+			n |= retries + 1;
+		}
+	}
+	sync_period = sysctl_sync_period(ipvs);
+	if (sync_period > 0) {
+		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE) &&
+		    pkts % sync_period != sysctl_sync_threshold(ipvs))
+			return 0;
+	} else if (sync_refresh_period <= 0 &&
+		   pkts != sysctl_sync_threshold(ipvs))
+		return 0;
+
+set:
+	cp->old_state = cp->state;
+	n = cmpxchg(&cp->sync_endtime, orig, n);
+	return n == orig || force;
+}
+
 /*
  *      Version 0 , could be switched in by sys_ctl.
  *      Add an ip_vs_conn information into the current sync_buff.
  */
-void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp)
+static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
+			       int pkts)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
 	struct ip_vs_sync_mesg_v0 *m;
@@ -468,6 +551,9 @@ void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp)
 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 		return;
 
+	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
+		return;
+
 	spin_lock(&ipvs->sync_buff_lock);
 	if (!ipvs->sync_buff) {
 		ipvs->sync_buff =
@@ -513,8 +599,14 @@ void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp)
 	spin_unlock(&ipvs->sync_buff_lock);
 
 	/* synchronize its controller if it has */
-	if (cp->control)
-		ip_vs_sync_conn(net, cp->control);
+	cp = cp->control;
+	if (cp) {
+		if (cp->flags & IP_VS_CONN_F_TEMPLATE)
+			pkts = atomic_add_return(1, &cp->in_pkts);
+		else
+			pkts = sysctl_sync_threshold(ipvs);
+		ip_vs_sync_conn(net, cp->control, pkts);
+	}
 }
 
 /*
@@ -522,7 +614,7 @@ void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp)
  *      Called by ip_vs_in.
  *      Sending Version 1 messages
  */
-void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp)
+void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
 	struct ip_vs_sync_mesg *m;
@@ -532,13 +624,16 @@ void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp)
 
 	/* Handle old version of the protocol */
 	if (sysctl_sync_ver(ipvs) == 0) {
-		ip_vs_sync_conn_v0(net, cp);
+		ip_vs_sync_conn_v0(net, cp, pkts);
 		return;
 	}
 	/* Do not sync ONE PACKET */
 	if (cp->flags & IP_VS_CONN_F_ONE_PACKET)
 		goto control;
 sloop:
+	if (!ip_vs_sync_conn_needed(ipvs, cp, pkts))
+		goto control;
+
 	/* Sanity checks */
 	pe_name_len = 0;
 	if (cp->pe_data_len) {
@@ -653,16 +748,10 @@ control:
 	cp = cp->control;
 	if (!cp)
 		return;
-	/*
-	 * Reduce sync rate for templates
-	 * i.e only increment in_pkts for Templates.
-	 */
-	if (cp->flags & IP_VS_CONN_F_TEMPLATE) {
-		int pkts = atomic_add_return(1, &cp->in_pkts);

[PATCH 14/17] ipvs: add support for sync threads

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	Allow master and backup servers to use many threads
for sync traffic. Add sysctl var "sync_ports" to define the
number of threads. Every thread will use single UDP port,
thread 0 will use the default port 8848 while last thread
will use port 8848+sync_ports-1.

	The sync traffic for connections is scheduled to many
master threads based on the cp address but one connection is
always assigned to same thread to avoid reordering of the
sync messages.

	Remove ip_vs_sync_switch_mode because this check
for sync mode change is still risky. Instead, check for mode
change under sync_buff_lock.

	Make sure the backup socks do not block on reading.

Special thanks to Aleksey Chudov for helping in all tests.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Tested-by: Aleksey Chudov <aleksey.chudov@gmail.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 include/net/ip_vs.h             |   34 +++-
 net/netfilter/ipvs/ip_vs_conn.c |    7 +
 net/netfilter/ipvs/ip_vs_ctl.c  |   29 ++-
 net/netfilter/ipvs/ip_vs_sync.c |  401 ++++++++++++++++++++++++---------------
 4 files changed, 305 insertions(+), 166 deletions(-)

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index 941df45..75824e2 100644
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -785,6 +785,16 @@ struct ip_vs_app {
 	void (*timeout_change)(struct ip_vs_app *app, int flags);
 };
 
+struct ipvs_master_sync_state {
+	struct list_head	sync_queue;
+	struct ip_vs_sync_buff	*sync_buff;
+	int			sync_queue_len;
+	unsigned int		sync_queue_delay;
+	struct task_struct	*master_thread;
+	struct delayed_work	master_wakeup_work;
+	struct netns_ipvs	*ipvs;
+};
+
 /* IPVS in network namespace */
 struct netns_ipvs {
 	int			gen;		/* Generation */
@@ -871,6 +881,7 @@ struct netns_ipvs {
 #endif
 	int			sysctl_snat_reroute;
 	int			sysctl_sync_ver;
+	int			sysctl_sync_ports;
 	int			sysctl_sync_qlen_max;
 	int			sysctl_sync_sock_size;
 	int			sysctl_cache_bypass;
@@ -894,16 +905,11 @@ struct netns_ipvs {
 	spinlock_t		est_lock;
 	struct timer_list	est_timer;	/* Estimation timer */
 	/* ip_vs_sync */
-	struct list_head	sync_queue;
-	int			sync_queue_len;
-	unsigned int		sync_queue_delay;
-	struct delayed_work	master_wakeup_work;
 	spinlock_t		sync_lock;
-	struct ip_vs_sync_buff  *sync_buff;
+	struct ipvs_master_sync_state *ms;
 	spinlock_t		sync_buff_lock;
-	struct sockaddr_in	sync_mcast_addr;
-	struct task_struct	*master_thread;
-	struct task_struct	*backup_thread;
+	struct task_struct	**backup_threads;
+	int			threads_mask;
 	int			send_mesg_maxlen;
 	int			recv_mesg_maxlen;
 	volatile int		sync_state;
@@ -927,6 +933,7 @@ struct netns_ipvs {
 #define IPVS_SYNC_SEND_DELAY	(HZ / 50)
 #define IPVS_SYNC_CHECK_PERIOD	HZ
 #define IPVS_SYNC_FLUSH_TIME	(HZ * 2)
+#define IPVS_SYNC_PORTS_MAX	(1 << 6)
 
 #ifdef CONFIG_SYSCTL
 
@@ -955,6 +962,11 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
 	return ipvs->sysctl_sync_ver;
 }
 
+static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
+{
+	return ACCESS_ONCE(ipvs->sysctl_sync_ports);
+}
+
 static inline int sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
 {
 	return ipvs->sysctl_sync_qlen_max;
@@ -992,6 +1004,11 @@ static inline int sysctl_sync_ver(struct netns_ipvs *ipvs)
 	return DEFAULT_SYNC_VER;
 }
 
+static inline int sysctl_sync_ports(struct netns_ipvs *ipvs)
+{
+	return 1;
+}
+
 static inline int sysctl_sync_qlen_max(struct netns_ipvs *ipvs)
 {
 	return IPVS_SYNC_QLEN_MAX;
@@ -1242,7 +1259,6 @@ extern struct ip_vs_stats ip_vs_stats;
 extern const struct ctl_path net_vs_ctl_path[];
 extern int sysctl_ip_vs_sync_ver;
 
-extern void ip_vs_sync_switch_mode(struct net *net, int mode);
 extern struct ip_vs_service *
 ip_vs_service_get(struct net *net, int af, __u32 fwmark, __u16 protocol,
 		  const union nf_inet_addr *vaddr, __be16 vport);
diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 46260fb..6a43c93 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -618,12 +618,19 @@ struct ip_vs_dest *ip_vs_try_bind_dest(struct ip_vs_conn *cp)
 	if (dest) {
 		struct ip_vs_proto_data *pd;
 
+		spin_lock(&cp->lock);
+		if (cp->dest) {
+			spin_unlock(&cp->lock);
+			return dest;
+		}
+
 		/* Applications work depending on the forwarding method
 		 * but better to reassign them always when binding dest */
 		if (cp->app)
 			ip_vs_unbind_app(cp);
 
 		ip_vs_bind_dest(cp, dest);
+		spin_unlock(&cp->lock);
 
 		/* Update its packet transmitter */
 		cp->packet_xmit = NULL;
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index 83bdbbc..0e599a4 100644
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -1657,9 +1657,24 @@ proc_do_sync_mode(ctl_table *table, int write,
 		if ((*valp < 0) || (*valp > 1)) {
 			/* Restore the correct value */
 			*valp = val;
-		} else {
-			struct net *net = current->nsproxy->net_ns;
-			ip_vs_sync_switch_mode(net, val);
+		}
+	}
+	return rc;
+}
+
+static int
+proc_do_sync_ports(ctl_table *table, int write,
+		   void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+	int *valp = table->data;
+	int val = *valp;
+	int rc;
+
+	rc = proc_dointvec(table, write, buffer, lenp, ppos);
+	if (write && (*valp != val)) {
+		if (*valp < 1 || !is_power_of_2(*valp)) {
+			/* Restore the correct value */
+			*valp = val;
 		}
 	}
 	return rc;
@@ -1723,6 +1738,12 @@ static struct ctl_table vs_vars[] = {
 		.proc_handler	= &proc_do_sync_mode,
 	},
 	{
+		.procname	= "sync_ports",
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= &proc_do_sync_ports,
+	},
+	{
 		.procname	= "sync_qlen_max",
 		.maxlen		= sizeof(int),
 		.mode		= 0644,
@@ -3693,6 +3714,8 @@ int __net_init ip_vs_control_net_init_sysctl(struct net *net)
 	tbl[idx++].data = &ipvs->sysctl_snat_reroute;
 	ipvs->sysctl_sync_ver = 1;
 	tbl[idx++].data = &ipvs->sysctl_sync_ver;
+	ipvs->sysctl_sync_ports = 1;
+	tbl[idx++].data = &ipvs->sysctl_sync_ports;
 	ipvs->sysctl_sync_qlen_max = nr_free_buffer_pages() / 32;
 	tbl[idx++].data = &ipvs->sysctl_sync_qlen_max;
 	ipvs->sysctl_sync_sock_size = 0;
diff --git a/net/netfilter/ipvs/ip_vs_sync.c b/net/netfilter/ipvs/ip_vs_sync.c
index 4aa9290..8550f37 100644
--- a/net/netfilter/ipvs/ip_vs_sync.c
+++ b/net/netfilter/ipvs/ip_vs_sync.c
@@ -196,6 +196,7 @@ struct ip_vs_sync_thread_data {
 	struct net *net;
 	struct socket *sock;
 	char *buf;
+	int id;
 };
 
 /* Version 0 definition of packet sizes */
@@ -271,13 +272,6 @@ struct ip_vs_sync_buff {
 	unsigned char           *end;
 };
 
-/* multicast addr */
-static struct sockaddr_in mcast_addr = {
-	.sin_family		= AF_INET,
-	.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT),
-	.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
-};
-
 /*
  * Copy of struct ip_vs_seq
  * From unaligned network order to aligned host order
@@ -300,22 +294,22 @@ static void hton_seq(struct ip_vs_seq *ho, struct ip_vs_seq *no)
 	put_unaligned_be32(ho->previous_delta, &no->previous_delta);
 }
 
-static inline struct ip_vs_sync_buff *sb_dequeue(struct netns_ipvs *ipvs)
+static inline struct ip_vs_sync_buff *
+sb_dequeue(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
 {
 	struct ip_vs_sync_buff *sb;
 
 	spin_lock_bh(&ipvs->sync_lock);
-	if (list_empty(&ipvs->sync_queue)) {
+	if (list_empty(&ms->sync_queue)) {
 		sb = NULL;
 		__set_current_state(TASK_INTERRUPTIBLE);
 	} else {
-		sb = list_entry(ipvs->sync_queue.next,
-				struct ip_vs_sync_buff,
+		sb = list_entry(ms->sync_queue.next, struct ip_vs_sync_buff,
 				list);
 		list_del(&sb->list);
-		ipvs->sync_queue_len--;
-		if (!ipvs->sync_queue_len)
-			ipvs->sync_queue_delay = 0;
+		ms->sync_queue_len--;
+		if (!ms->sync_queue_len)
+			ms->sync_queue_delay = 0;
 	}
 	spin_unlock_bh(&ipvs->sync_lock);
 
@@ -338,7 +332,7 @@ ip_vs_sync_buff_create(struct netns_ipvs *ipvs)
 		kfree(sb);
 		return NULL;
 	}
-	sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zeo now */
+	sb->mesg->reserved = 0;  /* old nr_conns i.e. must be zero now */
 	sb->mesg->version = SYNC_PROTO_VER;
 	sb->mesg->syncid = ipvs->master_syncid;
 	sb->mesg->size = sizeof(struct ip_vs_sync_mesg);
@@ -357,20 +351,21 @@ static inline void ip_vs_sync_buff_release(struct ip_vs_sync_buff *sb)
 	kfree(sb);
 }
 
-static inline void sb_queue_tail(struct netns_ipvs *ipvs)
+static inline void sb_queue_tail(struct netns_ipvs *ipvs,
+				 struct ipvs_master_sync_state *ms)
 {
-	struct ip_vs_sync_buff *sb = ipvs->sync_buff;
+	struct ip_vs_sync_buff *sb = ms->sync_buff;
 
 	spin_lock(&ipvs->sync_lock);
 	if (ipvs->sync_state & IP_VS_STATE_MASTER &&
-	    ipvs->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
-		if (!ipvs->sync_queue_len)
-			schedule_delayed_work(&ipvs->master_wakeup_work,
+	    ms->sync_queue_len < sysctl_sync_qlen_max(ipvs)) {
+		if (!ms->sync_queue_len)
+			schedule_delayed_work(&ms->master_wakeup_work,
 					      max(IPVS_SYNC_SEND_DELAY, 1));
-		ipvs->sync_queue_len++;
-		list_add_tail(&sb->list, &ipvs->sync_queue);
-		if ((++ipvs->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE)
-			wake_up_process(ipvs->master_thread);
+		ms->sync_queue_len++;
+		list_add_tail(&sb->list, &ms->sync_queue);
+		if ((++ms->sync_queue_delay) == IPVS_SYNC_WAKEUP_RATE)
+			wake_up_process(ms->master_thread);
 	} else
 		ip_vs_sync_buff_release(sb);
 	spin_unlock(&ipvs->sync_lock);
@@ -381,15 +376,15 @@ static inline void sb_queue_tail(struct netns_ipvs *ipvs)
  *	than the specified time or the specified time is zero.
  */
 static inline struct ip_vs_sync_buff *
-get_curr_sync_buff(struct netns_ipvs *ipvs, unsigned long time)
+get_curr_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms,
+		   unsigned long time)
 {
 	struct ip_vs_sync_buff *sb;
 
 	spin_lock_bh(&ipvs->sync_buff_lock);
-	if (ipvs->sync_buff &&
-	    time_after_eq(jiffies - ipvs->sync_buff->firstuse, time)) {
-		sb = ipvs->sync_buff;
-		ipvs->sync_buff = NULL;
+	sb = ms->sync_buff;
+	if (sb && time_after_eq(jiffies - sb->firstuse, time)) {
+		ms->sync_buff = NULL;
 		__set_current_state(TASK_RUNNING);
 	} else
 		sb = NULL;
@@ -397,31 +392,10 @@ get_curr_sync_buff(struct netns_ipvs *ipvs, unsigned long time)
 	return sb;
 }
 
-/*
- * Switch mode from sending version 0 or 1
- *  - must handle sync_buf
- */
-void ip_vs_sync_switch_mode(struct net *net, int mode)
+static inline int
+select_master_thread_id(struct netns_ipvs *ipvs, struct ip_vs_conn *cp)
 {
-	struct netns_ipvs *ipvs = net_ipvs(net);
-	struct ip_vs_sync_buff *sb;
-
-	spin_lock_bh(&ipvs->sync_buff_lock);
-	if (!(ipvs->sync_state & IP_VS_STATE_MASTER))
-		goto unlock;
-	sb = ipvs->sync_buff;
-	if (mode == sysctl_sync_ver(ipvs) || !sb)
-		goto unlock;
-
-	/* Buffer empty ? then let buf_create do the job  */
-	if (sb->mesg->size <= sizeof(struct ip_vs_sync_mesg)) {
-		ip_vs_sync_buff_release(sb);
-		ipvs->sync_buff = NULL;
-	} else
-		sb_queue_tail(ipvs);
-
-unlock:
-	spin_unlock_bh(&ipvs->sync_buff_lock);
+	return ((long) cp >> (1 + ilog2(sizeof(*cp)))) & ipvs->threads_mask;
 }
 
 /*
@@ -543,6 +517,9 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
 	struct netns_ipvs *ipvs = net_ipvs(net);
 	struct ip_vs_sync_mesg_v0 *m;
 	struct ip_vs_sync_conn_v0 *s;
+	struct ip_vs_sync_buff *buff;
+	struct ipvs_master_sync_state *ms;
+	int id;
 	int len;
 
 	if (unlikely(cp->af != AF_INET))
@@ -555,20 +532,37 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
 		return;
 
 	spin_lock(&ipvs->sync_buff_lock);
-	if (!ipvs->sync_buff) {
-		ipvs->sync_buff =
-			ip_vs_sync_buff_create_v0(ipvs);
-		if (!ipvs->sync_buff) {
+	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
+		spin_unlock(&ipvs->sync_buff_lock);
+		return;
+	}
+
+	id = select_master_thread_id(ipvs, cp);
+	ms = &ipvs->ms[id];
+	buff = ms->sync_buff;
+	if (buff) {
+		m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
+		/* Send buffer if it is for v1 */
+		if (!m->nr_conns) {
+			sb_queue_tail(ipvs, ms);
+			ms->sync_buff = NULL;
+			buff = NULL;
+		}
+	}
+	if (!buff) {
+		buff = ip_vs_sync_buff_create_v0(ipvs);
+		if (!buff) {
 			spin_unlock(&ipvs->sync_buff_lock);
 			pr_err("ip_vs_sync_buff_create failed.\n");
 			return;
 		}
+		ms->sync_buff = buff;
 	}
 
 	len = (cp->flags & IP_VS_CONN_F_SEQ_MASK) ? FULL_CONN_SIZE :
 		SIMPLE_CONN_SIZE;
-	m = (struct ip_vs_sync_mesg_v0 *)ipvs->sync_buff->mesg;
-	s = (struct ip_vs_sync_conn_v0 *)ipvs->sync_buff->head;
+	m = (struct ip_vs_sync_mesg_v0 *) buff->mesg;
+	s = (struct ip_vs_sync_conn_v0 *) buff->head;
 
 	/* copy members */
 	s->reserved = 0;
@@ -589,12 +583,12 @@ static void ip_vs_sync_conn_v0(struct net *net, struct ip_vs_conn *cp,
 
 	m->nr_conns++;
 	m->size += len;
-	ipvs->sync_buff->head += len;
+	buff->head += len;
 
 	/* check if there is a space for next one */
-	if (ipvs->sync_buff->head + FULL_CONN_SIZE > ipvs->sync_buff->end) {
-		sb_queue_tail(ipvs);
-		ipvs->sync_buff = NULL;
+	if (buff->head + FULL_CONN_SIZE > buff->end) {
+		sb_queue_tail(ipvs, ms);
+		ms->sync_buff = NULL;
 	}
 	spin_unlock(&ipvs->sync_buff_lock);
 
@@ -619,6 +613,9 @@ void ip_vs_sync_conn(struct net *net, struct ip_vs_conn *cp, int pkts)
 	struct netns_ipvs *ipvs = net_ipvs(net);
 	struct ip_vs_sync_mesg *m;
 	union ip_vs_sync_conn *s;
+	struct ip_vs_sync_buff *buff;
+	struct ipvs_master_sync_state *ms;
+	int id;
 	__u8 *p;
 	unsigned int len, pe_name_len, pad;
 
@@ -645,6 +642,13 @@ sloop:
 	}
 
 	spin_lock(&ipvs->sync_buff_lock);
+	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
+		spin_unlock(&ipvs->sync_buff_lock);
+		return;
+	}
+
+	id = select_master_thread_id(ipvs, cp);
+	ms = &ipvs->ms[id];
 
 #ifdef CONFIG_IP_VS_IPV6
 	if (cp->af == AF_INET6)
@@ -663,27 +667,32 @@ sloop:
 
 	/* check if there is a space for this one  */
 	pad = 0;
-	if (ipvs->sync_buff) {
-		pad = (4 - (size_t)ipvs->sync_buff->head) & 3;
-		if (ipvs->sync_buff->head + len + pad > ipvs->sync_buff->end) {
-			sb_queue_tail(ipvs);
-			ipvs->sync_buff = NULL;
+	buff = ms->sync_buff;
+	if (buff) {
+		m = buff->mesg;
+		pad = (4 - (size_t) buff->head) & 3;
+		/* Send buffer if it is for v0 */
+		if (buff->head + len + pad > buff->end || m->reserved) {
+			sb_queue_tail(ipvs, ms);
+			ms->sync_buff = NULL;
+			buff = NULL;
 			pad = 0;
 		}
 	}
 
-	if (!ipvs->sync_buff) {
-		ipvs->sync_buff = ip_vs_sync_buff_create(ipvs);
-		if (!ipvs->sync_buff) {
+	if (!buff) {
+		buff = ip_vs_sync_buff_create(ipvs);
+		if (!buff) {
 			spin_unlock(&ipvs->sync_buff_lock);
 			pr_err("ip_vs_sync_buff_create failed.\n");
 			return;
 		}
+		ms->sync_buff = buff;
+		m = buff->mesg;
 	}
 
-	m = ipvs->sync_buff->mesg;
-	p = ipvs->sync_buff->head;
-	ipvs->sync_buff->head += pad + len;
+	p = buff->head;
+	buff->head += pad + len;
 	m->size += pad + len;
 	/* Add ev. padding from prev. sync_conn */
 	while (pad--)
@@ -834,6 +843,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 		kfree(param->pe_data);
 
 		dest = cp->dest;
+		spin_lock(&cp->lock);
 		if ((cp->flags ^ flags) & IP_VS_CONN_F_INACTIVE &&
 		    !(flags & IP_VS_CONN_F_TEMPLATE) && dest) {
 			if (flags & IP_VS_CONN_F_INACTIVE) {
@@ -847,6 +857,7 @@ static void ip_vs_proc_conn(struct net *net, struct ip_vs_conn_param *param,
 		flags &= IP_VS_CONN_F_BACKUP_UPD_MASK;
 		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)
@@ -1399,9 +1410,15 @@ static int bind_mcastif_addr(struct socket *sock, char *ifname)
 /*
  *      Set up sending multicast socket over UDP
  */
-static struct socket *make_send_sock(struct net *net)
+static struct socket *make_send_sock(struct net *net, int id)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
+	/* multicast addr */
+	struct sockaddr_in mcast_addr = {
+		.sin_family		= AF_INET,
+		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
+		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
+	};
 	struct socket *sock;
 	int result;
 
@@ -1453,9 +1470,15 @@ error:
 /*
  *      Set up receiving multicast socket over UDP
  */
-static struct socket *make_receive_sock(struct net *net)
+static struct socket *make_receive_sock(struct net *net, int id)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
+	/* multicast addr */
+	struct sockaddr_in mcast_addr = {
+		.sin_family		= AF_INET,
+		.sin_port		= cpu_to_be16(IP_VS_SYNC_PORT + id),
+		.sin_addr.s_addr	= cpu_to_be32(IP_VS_SYNC_GROUP),
+	};
 	struct socket *sock;
 	int result;
 
@@ -1549,10 +1572,10 @@ ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
 	iov.iov_base     = buffer;
 	iov.iov_len      = (size_t)buflen;
 
-	len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, 0);
+	len = kernel_recvmsg(sock, &msg, &iov, 1, buflen, MSG_DONTWAIT);
 
 	if (len < 0)
-		return -1;
+		return len;
 
 	LeaveFunction(7);
 	return len;
@@ -1561,44 +1584,47 @@ ip_vs_receive(struct socket *sock, char *buffer, const size_t buflen)
 /* Wakeup the master thread for sending */
 static void master_wakeup_work_handler(struct work_struct *work)
 {
-	struct netns_ipvs *ipvs = container_of(work, struct netns_ipvs,
-					       master_wakeup_work.work);
+	struct ipvs_master_sync_state *ms =
+		container_of(work, struct ipvs_master_sync_state,
+			     master_wakeup_work.work);
+	struct netns_ipvs *ipvs = ms->ipvs;
 
 	spin_lock_bh(&ipvs->sync_lock);
-	if (ipvs->sync_queue_len &&
-	    ipvs->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
-		ipvs->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
-		wake_up_process(ipvs->master_thread);
+	if (ms->sync_queue_len &&
+	    ms->sync_queue_delay < IPVS_SYNC_WAKEUP_RATE) {
+		ms->sync_queue_delay = IPVS_SYNC_WAKEUP_RATE;
+		wake_up_process(ms->master_thread);
 	}
 	spin_unlock_bh(&ipvs->sync_lock);
 }
 
 /* Get next buffer to send */
 static inline struct ip_vs_sync_buff *
-next_sync_buff(struct netns_ipvs *ipvs)
+next_sync_buff(struct netns_ipvs *ipvs, struct ipvs_master_sync_state *ms)
 {
 	struct ip_vs_sync_buff *sb;
 
-	sb = sb_dequeue(ipvs);
+	sb = sb_dequeue(ipvs, ms);
 	if (sb)
 		return sb;
 	/* Do not delay entries in buffer for more than 2 seconds */
-	return get_curr_sync_buff(ipvs, IPVS_SYNC_FLUSH_TIME);
+	return get_curr_sync_buff(ipvs, ms, IPVS_SYNC_FLUSH_TIME);
 }
 
 static int sync_thread_master(void *data)
 {
 	struct ip_vs_sync_thread_data *tinfo = data;
 	struct netns_ipvs *ipvs = net_ipvs(tinfo->net);
+	struct ipvs_master_sync_state *ms = &ipvs->ms[tinfo->id];
 	struct sock *sk = tinfo->sock->sk;
 	struct ip_vs_sync_buff *sb;
 
 	pr_info("sync thread started: state = MASTER, mcast_ifn = %s, "
-		"syncid = %d\n",
-		ipvs->master_mcast_ifn, ipvs->master_syncid);
+		"syncid = %d, id = %d\n",
+		ipvs->master_mcast_ifn, ipvs->master_syncid, tinfo->id);
 
 	for (;;) {
-		sb = next_sync_buff(ipvs);
+		sb = next_sync_buff(ipvs, ms);
 		if (unlikely(kthread_should_stop()))
 			break;
 		if (!sb) {
@@ -1624,12 +1650,12 @@ done:
 		ip_vs_sync_buff_release(sb);
 
 	/* clean up the sync_buff queue */
-	while ((sb = sb_dequeue(ipvs)))
+	while ((sb = sb_dequeue(ipvs, ms)))
 		ip_vs_sync_buff_release(sb);
 	__set_current_state(TASK_RUNNING);
 
 	/* clean up the current sync_buff */
-	sb = get_curr_sync_buff(ipvs, 0);
+	sb = get_curr_sync_buff(ipvs, ms, 0);
 	if (sb)
 		ip_vs_sync_buff_release(sb);
 
@@ -1648,8 +1674,8 @@ static int sync_thread_backup(void *data)
 	int len;
 
 	pr_info("sync thread started: state = BACKUP, mcast_ifn = %s, "
-		"syncid = %d\n",
-		ipvs->backup_mcast_ifn, ipvs->backup_syncid);
+		"syncid = %d, id = %d\n",
+		ipvs->backup_mcast_ifn, ipvs->backup_syncid, tinfo->id);
 
 	while (!kthread_should_stop()) {
 		wait_event_interruptible(*sk_sleep(tinfo->sock->sk),
@@ -1661,7 +1687,8 @@ static int sync_thread_backup(void *data)
 			len = ip_vs_receive(tinfo->sock, tinfo->buf,
 					ipvs->recv_mesg_maxlen);
 			if (len <= 0) {
-				pr_err("receiving message error\n");
+				if (len != -EAGAIN)
+					pr_err("receiving message error\n");
 				break;
 			}
 
@@ -1685,90 +1712,140 @@ static int sync_thread_backup(void *data)
 int start_sync_thread(struct net *net, int state, char *mcast_ifn, __u8 syncid)
 {
 	struct ip_vs_sync_thread_data *tinfo;
-	struct task_struct **realtask, *task;
+	struct task_struct **array = NULL, *task;
 	struct socket *sock;
 	struct netns_ipvs *ipvs = net_ipvs(net);
-	char *name, *buf = NULL;
+	char *name;
 	int (*threadfn)(void *data);
+	int id, count;
 	int result = -ENOMEM;
 
 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
 	IP_VS_DBG(7, "Each ip_vs_sync_conn entry needs %Zd bytes\n",
 		  sizeof(struct ip_vs_sync_conn_v0));
 
+	if (!ipvs->sync_state) {
+		count = clamp(sysctl_sync_ports(ipvs), 1, IPVS_SYNC_PORTS_MAX);
+		ipvs->threads_mask = count - 1;
+	} else
+		count = ipvs->threads_mask + 1;
 
 	if (state == IP_VS_STATE_MASTER) {
-		if (ipvs->master_thread)
+		if (ipvs->ms)
 			return -EEXIST;
 
 		strlcpy(ipvs->master_mcast_ifn, mcast_ifn,
 			sizeof(ipvs->master_mcast_ifn));
 		ipvs->master_syncid = syncid;
-		realtask = &ipvs->master_thread;
-		name = "ipvs_master:%d";
+		name = "ipvs-m:%d:%d";
 		threadfn = sync_thread_master;
-		ipvs->sync_queue_len = 0;
-		ipvs->sync_queue_delay = 0;
-		INIT_DELAYED_WORK(&ipvs->master_wakeup_work,
-				  master_wakeup_work_handler);
-		sock = make_send_sock(net);
 	} else if (state == IP_VS_STATE_BACKUP) {
-		if (ipvs->backup_thread)
+		if (ipvs->backup_threads)
 			return -EEXIST;
 
 		strlcpy(ipvs->backup_mcast_ifn, mcast_ifn,
 			sizeof(ipvs->backup_mcast_ifn));
 		ipvs->backup_syncid = syncid;
-		realtask = &ipvs->backup_thread;
-		name = "ipvs_backup:%d";
+		name = "ipvs-b:%d:%d";
 		threadfn = sync_thread_backup;
-		sock = make_receive_sock(net);
 	} else {
 		return -EINVAL;
 	}
 
-	if (IS_ERR(sock)) {
-		result = PTR_ERR(sock);
-		goto out;
-	}
+	if (state == IP_VS_STATE_MASTER) {
+		struct ipvs_master_sync_state *ms;
 
-	set_sync_mesg_maxlen(net, state);
-	if (state == IP_VS_STATE_BACKUP) {
-		buf = kmalloc(ipvs->recv_mesg_maxlen, GFP_KERNEL);
-		if (!buf)
-			goto outsocket;
+		ipvs->ms = kzalloc(count * sizeof(ipvs->ms[0]), GFP_KERNEL);
+		if (!ipvs->ms)
+			goto out;
+		ms = ipvs->ms;
+		for (id = 0; id < count; id++, ms++) {
+			INIT_LIST_HEAD(&ms->sync_queue);
+			ms->sync_queue_len = 0;
+			ms->sync_queue_delay = 0;
+			INIT_DELAYED_WORK(&ms->master_wakeup_work,
+					  master_wakeup_work_handler);
+			ms->ipvs = ipvs;
+		}
+	} else {
+		array = kzalloc(count * sizeof(struct task_struct *),
+				GFP_KERNEL);
+		if (!array)
+			goto out;
 	}
+	set_sync_mesg_maxlen(net, state);
 
-	tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
-	if (!tinfo)
-		goto outbuf;
-
-	tinfo->net = net;
-	tinfo->sock = sock;
-	tinfo->buf = buf;
+	tinfo = NULL;
+	for (id = 0; id < count; id++) {
+		if (state == IP_VS_STATE_MASTER)
+			sock = make_send_sock(net, id);
+		else
+			sock = make_receive_sock(net, id);
+		if (IS_ERR(sock)) {
+			result = PTR_ERR(sock);
+			goto outtinfo;
+		}
+		tinfo = kmalloc(sizeof(*tinfo), GFP_KERNEL);
+		if (!tinfo)
+			goto outsocket;
+		tinfo->net = net;
+		tinfo->sock = sock;
+		if (state == IP_VS_STATE_BACKUP) {
+			tinfo->buf = kmalloc(ipvs->recv_mesg_maxlen,
+					     GFP_KERNEL);
+			if (!tinfo->buf)
+				goto outtinfo;
+		}
+		tinfo->id = id;
 
-	task = kthread_run(threadfn, tinfo, name, ipvs->gen);
-	if (IS_ERR(task)) {
-		result = PTR_ERR(task);
-		goto outtinfo;
+		task = kthread_run(threadfn, tinfo, name, ipvs->gen, id);
+		if (IS_ERR(task)) {
+			result = PTR_ERR(task);
+			goto outtinfo;
+		}
+		tinfo = NULL;
+		if (state == IP_VS_STATE_MASTER)
+			ipvs->ms[id].master_thread = task;
+		else
+			array[id] = task;
 	}
 
 	/* mark as active */
-	*realtask = task;
+
+	if (state == IP_VS_STATE_BACKUP)
+		ipvs->backup_threads = array;
+	spin_lock_bh(&ipvs->sync_buff_lock);
 	ipvs->sync_state |= state;
+	spin_unlock_bh(&ipvs->sync_buff_lock);
 
 	/* increase the module use count */
 	ip_vs_use_count_inc();
 
 	return 0;
 
-outtinfo:
-	kfree(tinfo);
-outbuf:
-	kfree(buf);
 outsocket:
 	sk_release_kernel(sock->sk);
+
+outtinfo:
+	if (tinfo) {
+		sk_release_kernel(tinfo->sock->sk);
+		kfree(tinfo->buf);
+		kfree(tinfo);
+	}
+	count = id;
+	while (count-- > 0) {
+		if (state == IP_VS_STATE_MASTER)
+			kthread_stop(ipvs->ms[count].master_thread);
+		else
+			kthread_stop(array[count]);
+	}
+	kfree(array);
+
 out:
+	if (!(ipvs->sync_state & IP_VS_STATE_MASTER)) {
+		kfree(ipvs->ms);
+		ipvs->ms = NULL;
+	}
 	return result;
 }
 
@@ -1776,39 +1853,60 @@ out:
 int stop_sync_thread(struct net *net, int state)
 {
 	struct netns_ipvs *ipvs = net_ipvs(net);
+	struct task_struct **array;
+	int id;
 	int retc = -EINVAL;
 
 	IP_VS_DBG(7, "%s(): pid %d\n", __func__, task_pid_nr(current));
 
 	if (state == IP_VS_STATE_MASTER) {
-		if (!ipvs->master_thread)
+		if (!ipvs->ms)
 			return -ESRCH;
 
-		pr_info("stopping master sync thread %d ...\n",
-			task_pid_nr(ipvs->master_thread));
-
 		/*
 		 * The lock synchronizes with sb_queue_tail(), so that we don't
 		 * add sync buffers to the queue, when we are already in
 		 * progress of stopping the master sync daemon.
 		 */
 
-		spin_lock_bh(&ipvs->sync_lock);
+		spin_lock_bh(&ipvs->sync_buff_lock);
+		spin_lock(&ipvs->sync_lock);
 		ipvs->sync_state &= ~IP_VS_STATE_MASTER;
-		spin_unlock_bh(&ipvs->sync_lock);
-		cancel_delayed_work_sync(&ipvs->master_wakeup_work);
-		retc = kthread_stop(ipvs->master_thread);
-		ipvs->master_thread = NULL;
+		spin_unlock(&ipvs->sync_lock);
+		spin_unlock_bh(&ipvs->sync_buff_lock);
+
+		retc = 0;
+		for (id = ipvs->threads_mask; id >= 0; id--) {
+			struct ipvs_master_sync_state *ms = &ipvs->ms[id];
+			int ret;
+
+			pr_info("stopping master sync thread %d ...\n",
+				task_pid_nr(ms->master_thread));
+			cancel_delayed_work_sync(&ms->master_wakeup_work);
+			ret = kthread_stop(ms->master_thread);
+			if (retc >= 0)
+				retc = ret;
+		}
+		kfree(ipvs->ms);
+		ipvs->ms = NULL;
 	} else if (state == IP_VS_STATE_BACKUP) {
-		if (!ipvs->backup_thread)
+		if (!ipvs->backup_threads)
 			return -ESRCH;
 
-		pr_info("stopping backup sync thread %d ...\n",
-			task_pid_nr(ipvs->backup_thread));
-
 		ipvs->sync_state &= ~IP_VS_STATE_BACKUP;
-		retc = kthread_stop(ipvs->backup_thread);
-		ipvs->backup_thread = NULL;
+		array = ipvs->backup_threads;
+		retc = 0;
+		for (id = ipvs->threads_mask; id >= 0; id--) {
+			int ret;
+
+			pr_info("stopping backup sync thread %d ...\n",
+				task_pid_nr(array[id]));
+			ret = kthread_stop(array[id]);
+			if (retc >= 0)
+				retc = ret;
+		}
+		kfree(array);
+		ipvs->backup_threads = NULL;
 	}
 
 	/* decrease the module use count */
@@ -1825,13 +1923,8 @@ int __net_init ip_vs_sync_net_init(struct net *net)
 	struct netns_ipvs *ipvs = net_ipvs(net);
 
 	__mutex_init(&ipvs->sync_mutex, "ipvs->sync_mutex", &__ipvs_sync_key);
-	INIT_LIST_HEAD(&ipvs->sync_queue);
 	spin_lock_init(&ipvs->sync_lock);
 	spin_lock_init(&ipvs->sync_buff_lock);

[PATCH 15/17] ipvs: optimize the use of flags in ip_vs_bind_dest

[Simon Horman]

From: Julian Anastasov <ja@ssi.bg>

	cp->flags is marked volatile but ip_vs_bind_dest
can safely modify the flags, so save some CPU cycles by
using temp variable.

Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_conn.c |   15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index 6a43c93..7f21b91 100644
--- a/net/netfilter/ipvs/ip_vs_conn.c
+++ b/net/netfilter/ipvs/ip_vs_conn.c
@@ -548,6 +548,7 @@ static inline void
 ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 {
 	unsigned int conn_flags;
+	__u32 flags;
 
 	/* if dest is NULL, then return directly */
 	if (!dest)
@@ -559,17 +560,19 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 	conn_flags = atomic_read(&dest->conn_flags);
 	if (cp->protocol != IPPROTO_UDP)
 		conn_flags &= ~IP_VS_CONN_F_ONE_PACKET;
+	flags = cp->flags;
 	/* Bind with the destination and its corresponding transmitter */
-	if (cp->flags & IP_VS_CONN_F_SYNC) {
+	if (flags & IP_VS_CONN_F_SYNC) {
 		/* if the connection is not template and is created
 		 * by sync, preserve the activity flag.
 		 */
-		if (!(cp->flags & IP_VS_CONN_F_TEMPLATE))
+		if (!(flags & IP_VS_CONN_F_TEMPLATE))
 			conn_flags &= ~IP_VS_CONN_F_INACTIVE;
 		/* connections inherit forwarding method from dest */
-		cp->flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT);
+		flags &= ~(IP_VS_CONN_F_FWD_MASK | IP_VS_CONN_F_NOOUTPUT);
 	}
-	cp->flags |= conn_flags;
+	flags |= conn_flags;
+	cp->flags = flags;
 	cp->dest = dest;
 
 	IP_VS_DBG_BUF(7, "Bind-dest %s c:%s:%d v:%s:%d "
@@ -584,11 +587,11 @@ ip_vs_bind_dest(struct ip_vs_conn *cp, struct ip_vs_dest *dest)
 		      atomic_read(&dest->refcnt));
 
 	/* Update the connection counters */
-	if (!(cp->flags & IP_VS_CONN_F_TEMPLATE)) {
+	if (!(flags & IP_VS_CONN_F_TEMPLATE)) {
 		/* It is a normal connection, so modify the counters
 		 * according to the flags, later the protocol can
 		 * update them on state change */
-		if (!(cp->flags & IP_VS_CONN_F_INACTIVE))
+		if (!(flags & IP_VS_CONN_F_INACTIVE))
 			atomic_inc(&dest->activeconns);
 		else
 			atomic_inc(&dest->inactconns);
-- 
1.7.9.5

[PATCH 16/17] IPVS: ip_vs_ftp.c: local functions should not be exposed globally

[Simon Horman]

From: H Hartley Sweeten <hartleys@visionengravers.com>

Functions not referenced outside of a source file should be marked
static to prevent it from being exposed globally.

This quiets the sparse warnings:

warning: symbol 'ip_vs_ftp_init' was not declared. Should it be static?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_ftp.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_ftp.c b/net/netfilter/ipvs/ip_vs_ftp.c
index debb8c7..091bec9 100644
--- a/net/netfilter/ipvs/ip_vs_ftp.c
+++ b/net/netfilter/ipvs/ip_vs_ftp.c
@@ -483,7 +483,7 @@ static struct pernet_operations ip_vs_ftp_ops = {
 	.exit = __ip_vs_ftp_exit,
 };
 
-int __init ip_vs_ftp_init(void)
+static int __init ip_vs_ftp_init(void)
 {
 	int rv;
 
-- 
1.7.9.5

[PATCH 17/17] IPVS: ip_vs_proto.c: local functions should not be exposed globally

[Simon Horman]

From: H Hartley Sweeten <hartleys@visionengravers.com>

Functions not referenced outside of a source file should be marked
static to prevent it from being exposed globally.

This quiets the sparse warnings:

warning: symbol '__ipvs_proto_data_get' was not declared. Should it be static?

Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Simon Horman <horms@verge.net.au>
---
 net/netfilter/ipvs/ip_vs_proto.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/netfilter/ipvs/ip_vs_proto.c b/net/netfilter/ipvs/ip_vs_proto.c
index 8726488..e3f4bb0 100644
--- a/net/netfilter/ipvs/ip_vs_proto.c
+++ b/net/netfilter/ipvs/ip_vs_proto.c
@@ -153,7 +153,7 @@ EXPORT_SYMBOL(ip_vs_proto_get);
 /*
  *	get ip_vs_protocol object data by netns and proto
  */
-struct ip_vs_proto_data *
+static struct ip_vs_proto_data *
 __ipvs_proto_data_get(struct netns_ipvs *ipvs, unsigned short proto)
 {
 	struct ip_vs_proto_data *pd;
-- 
1.7.9.5

Re: [GIT PULL next-net] IPVS

[Simon Horman]

On Wed, May 02, 2012 at 10:24:44AM +0900, Simon Horman wrote:
> Hi Pablo,
> 
> please consider the following 5 changes for 3.4, they are all bug fixes.
> I would also like these changes considered for stable.

Hi Pablo,

Hans has pointed out to me that the series should include one more patch.
I will send an updated series ASAP.

Re: [GIT PULL next-net] IPVS

[Simon Horman]

On Wed, May 02, 2012 at 02:53:49PM +0900, Simon Horman wrote:
> On Wed, May 02, 2012 at 10:24:44AM +0900, Simon Horman wrote:
> > Hi Pablo,
> > 
> > please consider the following 5 changes for 3.4, they are all bug fixes.
> > I would also like these changes considered for stable.
> 
> Hi Pablo,
> 
> Hans has pointed out to me that the series should include one more patch.
> I will send an updated series ASAP.

Also, the pull request will be for 3.5, not 3.4.
Cut and paste silliness my me, sorry.