[TCP]: Add tcp_dec_pcount_approx int variant

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

2 files changed, 11 insertions, 12 deletions

diff --git a/include/net/tcp.h b/include/net/tcp.h
index dde04afbe0a4..9d3438f6b52f 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -599,16 +599,21 @@ static inline int tcp_skb_mss(const struct sk_buff *skb)
         return skb_shinfo(skb)->gso_size;
 }
 
-static inline void tcp_dec_pcount_approx(__u32 *count,
-                                         const struct sk_buff *skb)
+static inline void tcp_dec_pcount_approx_int(__u32 *count, const int decr)
 {
         if (*count) {
-                *count -= tcp_skb_pcount(skb);
+                *count -= decr;
                 if ((int)*count < 0)
                         *count = 0;
         }
 }
 
+static inline void tcp_dec_pcount_approx(__u32 *count,
+                                         const struct sk_buff *skb)
+{
+        tcp_dec_pcount_approx_int(count, tcp_skb_pcount(skb));
+}
+
 static inline void tcp_packets_out_inc(struct sock *sk,
                                        const struct sk_buff *skb)
 {
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 3abe22e4b576..3c8c8e7f6f6d 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -740,22 +740,16 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss
                 if (diff > 0) {
                         /* Adjust Reno SACK estimate. */
                         if (!tp->rx_opt.sack_ok) {
-                                tp->sacked_out -= diff;
-                                if ((int)tp->sacked_out < 0)
-                                        tp->sacked_out = 0;
+                                tcp_dec_pcount_approx_int(&tp->sacked_out, diff);
                                 tcp_sync_left_out(tp);
                         }
 
-                        tp->fackets_out -= diff;
-                        if ((int)tp->fackets_out < 0)
-                                tp->fackets_out = 0;
+                        tcp_dec_pcount_approx_int(&tp->fackets_out, diff);
                         /* SACK fastpath might overwrite it unless dealt with */
                         if (tp->fastpath_skb_hint != NULL &&
                             after(TCP_SKB_CB(tp->fastpath_skb_hint)->seq,
                                   TCP_SKB_CB(skb)->seq)) {
-                                tp->fastpath_cnt_hint -= diff;
-                                if ((int)tp->fastpath_cnt_hint < 0)
-                                        tp->fastpath_cnt_hint = 0;
+                                tcp_dec_pcount_approx_int(&tp->fastpath_cnt_hint, diff);
                         }
                 }
         }