ipvs: optimize the use of flags in ip_vs_bind_dest

	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>

1 files changed, 9 insertions, 6 deletions

diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c
index c7edf2022c3..1548df9a752 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 "
@@ -584,12 +587,12 @@ 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);