tcp: add some mibs to track collapsing

Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/snmp.h b/include/linux/snmp.h
index 7a6e6bb..aee3f1e 100644 (file)
--- a/include/linux/snmp.h
+++ b/include/linux/snmp.h
@@ -216,6 +216,9 @@ enum
        LINUX_MIB_TCPSPURIOUSRTOS,              /* TCPSpuriousRTOs */
        LINUX_MIB_TCPMD5NOTFOUND,               /* TCPMD5NotFound */
        LINUX_MIB_TCPMD5UNEXPECTED,             /* TCPMD5Unexpected */
+       LINUX_MIB_SACKSHIFTED,
+       LINUX_MIB_SACKMERGED,
+       LINUX_MIB_SACKSHIFTFALLBACK,
        __LINUX_MIB_MAX
 };
 

diff --git a/net/ipv4/proc.c b/net/ipv4/proc.c
index a631a1f..731789b 100644 (file)
--- a/net/ipv4/proc.c
+++ b/net/ipv4/proc.c
@@ -234,6 +234,9 @@ static const struct snmp_mib snmp4_net_list[] = {
        SNMP_MIB_ITEM("TCPSpuriousRTOs", LINUX_MIB_TCPSPURIOUSRTOS),
        SNMP_MIB_ITEM("TCPMD5NotFound", LINUX_MIB_TCPMD5NOTFOUND),
        SNMP_MIB_ITEM("TCPMD5Unexpected", LINUX_MIB_TCPMD5UNEXPECTED),
+       SNMP_MIB_ITEM("TCPSackShifted", LINUX_MIB_SACKSHIFTED),
+       SNMP_MIB_ITEM("TCPSackMerged", LINUX_MIB_SACKMERGED),
+       SNMP_MIB_ITEM("TCPSackShiftFallback", LINUX_MIB_SACKSHIFTFALLBACK),
        SNMP_MIB_SENTINEL
 };
 

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index e6291dd..9f8a80b 100644 (file)
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1415,6 +1415,7 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *prev,
 
        if (skb->len > 0) {
                BUG_ON(!tcp_skb_pcount(skb));
+               NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_SACKSHIFTED);
                return 0;
        }
 
@@ -1436,6 +1437,8 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *prev,
        tcp_unlink_write_queue(skb, sk);
        sk_wmem_free_skb(sk, skb);
 
+       NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_SACKMERGED);
+
        return 1;
 }
 
@@ -1594,6 +1597,7 @@ noop:
        return skb;
 
 fallback:
+       NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_SACKSHIFTFALLBACK);
        return NULL;
 }