tcp: fix tso not work in single buffer issue

Type: fix

Signed-off-by: Simon Zhang <yuwei1.zhang@intel.com>
Change-Id: Iddb6fd41812e8c97af58859ef43279cfc0f9d1df
Signed-off-by: Simon Zhang <yuwei1.zhang@intel.com>
(cherry picked from commit 8a047ed741072bdb8d93b0841473eae06ae3c9d0)

2 files changed, 9 insertions, 6 deletions

diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index 8467ea4fd67..5ffb1e27ab8 100644
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -1189,7 +1189,7 @@ tcp_session_cal_goal_size (tcp_connection_t * tc)
   goal_size = TCP_MAX_GSO_SZ - tc->snd_mss % TCP_MAX_GSO_SZ;
   goal_size = clib_min (goal_size, tc->snd_wnd / 2);
 
-  return goal_size;
+  return goal_size > tc->snd_mss ? goal_size : tc->snd_mss;
 }
 
 /**
diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c
index 081a6bf521a..a7b0e398d36 100644
--- a/src/vnet/tcp/tcp_output.c
+++ b/src/vnet/tcp/tcp_output.c
@@ -2261,13 +2261,16 @@ tcp_output_push_ip (vlib_main_t * vm, vlib_buffer_t * b0,
 always_inline void
 tcp_check_if_gso (tcp_connection_t * tc, vlib_buffer_t * b)
 {
-  if (PREDICT_TRUE (!(b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID)))
+  if (!tc->is_tso)
     return;
-  u16 data_len =
-    b->current_length + b->total_length_not_including_first_buffer -
-    sizeof (tcp_header_t) - tc->snd_opts_len;
+  u16 data_len = b->current_length - sizeof (tcp_header_t) - tc->snd_opts_len;
 
-  if (data_len > tc->snd_mss)
+  if (PREDICT_FALSE (b->flags & VLIB_BUFFER_TOTAL_LENGTH_VALID))
+    data_len += b->total_length_not_including_first_buffer;
+
+  if (PREDICT_TRUE (data_len <= tc->snd_mss))
+    return;
+  else
     {
       ASSERT ((b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID) != 0);
       ASSERT ((b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID) != 0);