tcp: simplify tcp_current_mss
There's very little need for most of the callsites to get
tp->xmit_goal_size updated. That will cost us divide as is,
so slice the function in two. Also, the only users of the
tp->xmit_goal_size are directly behind tcp_current_mss(),
so there's no need to store that variable into tcp_sock
at all! The drop of xmit_goal_size currently leaves 16-bit
hole and some reorganization would again be necessary to
change that (but I'm aiming to fill that hole with u16
xmit_goal_size_segs to cache the results of the remaining
divide to get that tso on regression).
Bring xmit_goal_size parts into tcp.c
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Cc: Evgeniy Polyakov <zbr@ioremap.net>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 255ca35..e54c76d 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -481,7 +481,16 @@
}
extern unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu);
-extern unsigned int tcp_current_mss(struct sock *sk, int large);
+extern unsigned int tcp_current_mss(struct sock *sk);
+
+/* Bound MSS / TSO packet size with the half of the window */
+static inline int tcp_bound_to_half_wnd(struct tcp_sock *tp, int pktsize)
+{
+ if (tp->max_window && pktsize > (tp->max_window >> 1))
+ return max(tp->max_window >> 1, 68U - tp->tcp_header_len);
+ else
+ return pktsize;
+}
/* tcp.c */
extern void tcp_get_info(struct sock *, struct tcp_info *);
@@ -822,7 +831,7 @@
{
struct tcp_sock *tp = tcp_sk(sk);
- __tcp_push_pending_frames(sk, tcp_current_mss(sk, 1), tp->nonagle);
+ __tcp_push_pending_frames(sk, tcp_current_mss(sk), tp->nonagle);
}
static inline void tcp_init_wl(struct tcp_sock *tp, u32 seq)