vlib: refactor checksum offload support

Type: refactor

This patch refactors the offload flags in vlib_buffer_t.
There are two main reasons behind this refactoring.
First, offload flags are insufficient to represent outer
and inner headers offloads. Second, room for these flags
in first cacheline of vlib_buffer_t is also limited.

This patch introduces a generic offload flag in first
cacheline. And detailed offload flags in 2nd cacheline
of the structure for performance optimization.

Change-Id: Icc363a142fb9208ec7113ab5bbfc8230181f6004
Signed-off-by: Mohsin Kazmi <sykazmi@cisco.com>

1 files changed, 19 insertions, 1 deletions

diff --git a/src/vnet/buffer.c b/src/vnet/buffer.c
index 3cb6b948d2b..b41036d8124 100644
--- a/src/vnet/buffer.c
+++ b/src/vnet/buffer.c
@@ -16,6 +16,18 @@
 #include <vlib/vlib.h>
 #include <vnet/buffer.h>
 
+u8 *
+format_vnet_buffer_offload (u8 *s, va_list *args)
+{
+  vlib_buffer_t *b = va_arg (*args, vlib_buffer_t *);
+
+#define _(bit, name, ss, v)                                                   \
+  if (v && (vnet_buffer2 (b)->oflags & VNET_BUFFER_OFFLOAD_F_##name))         \
+    s = format (s, "%s ", ss);
+  foreach_vnet_buffer_offload_flag
+#undef _
+    return s;
+}
 
 u8 *
 format_vnet_buffer (u8 * s, va_list * args)
@@ -29,7 +41,10 @@ format_vnet_buffer (u8 * s, va_list * args)
     a = format (a, "%s ", ss);
   foreach_vnet_buffer_flag
 #undef _
-    if (b->flags & VNET_BUFFER_F_L2_HDR_OFFSET_VALID)
+    if (b->flags & VNET_BUFFER_F_OFFLOAD) a =
+      format (a, "%U ", format_vnet_buffer_offload, b);
+
+  if (b->flags & VNET_BUFFER_F_L2_HDR_OFFSET_VALID)
     a = format (a, "l2-hdr-offset %d ", vnet_buffer (b)->l2_hdr_offset);
 
   if (b->flags & VNET_BUFFER_F_L3_HDR_OFFSET_VALID)
@@ -38,6 +53,9 @@ format_vnet_buffer (u8 * s, va_list * args)
   if (b->flags & VNET_BUFFER_F_L4_HDR_OFFSET_VALID)
     a = format (a, "l4-hdr-offset %d ", vnet_buffer (b)->l4_hdr_offset);
 
+  if (b->flags & VNET_BUFFER_F_GSO)
+    a = format (a, "gso gso-size %d", vnet_buffer2 (b)->gso_size);
+
   if (b->flags & VNET_BUFFER_F_QOS_DATA_VALID)
     a = format (a, "qos %d.%d ",
 		vnet_buffer2 (b)->qos.bits, vnet_buffer2 (b)->qos.source);