tcp: Apply device TSO segment limit earlier
[ Upstream commit 1485348d2424e1131ea42efc033cbd9366462b01 ]
Cache the device gso_max_segs in sock::sk_gso_max_segs and use it to
limit the size of TSO skbs. This avoids the need to fall back to
software GSO for local TCP senders.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index d6feb1e..367bdaf 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -740,7 +740,9 @@
old_size_goal + mss_now > xmit_size_goal)) {
xmit_size_goal = old_size_goal;
} else {
- tp->xmit_size_goal_segs = xmit_size_goal / mss_now;
+ tp->xmit_size_goal_segs =
+ min_t(u16, xmit_size_goal / mss_now,
+ sk->sk_gso_max_segs);
xmit_size_goal = tp->xmit_size_goal_segs * mss_now;
}
}