tcp, flow: Remove redundant information, repack connection structures

Some information we explicitly store in the TCP connection is now
duplicated in the common flow structure.  Access it from there instead, and
remove it from the TCP specific structure.   With that done we can reorder
both the "tap" and "splice" TCP structures a bit to get better packing for
the new combined flow table entries.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

1 files changed, 15 insertions, 25 deletions

diff --git a/tcp_conn.h b/tcp_conn.h
index f80ef67..4e7c57a 100644
--- a/tcp_conn.h
+++ b/tcp_conn.h
@@ -13,19 +13,16 @@
  * struct tcp_tap_conn - Descriptor for a TCP connection (not spliced)
  * @f:			Generic flow information
  * @in_epoll:		Is the connection in the epoll set?
+ * @retrans:		Number of retransmissions occurred due to ACK_TIMEOUT
+ * @ws_from_tap:	Window scaling factor advertised from tap/guest
+ * @ws_to_tap:		Window scaling factor advertised to tap/guest
  * @tap_mss:		MSS advertised by tap/guest, rounded to 2 ^ TCP_MSS_BITS
  * @sock:		Socket descriptor number
  * @events:		Connection events, implying connection states
  * @timer:		timerfd descriptor for timeout events
  * @flags:		Connection flags representing internal attributes
- * @retrans:		Number of retransmissions occurred due to ACK_TIMEOUT
- * @ws_from_tap:	Window scaling factor advertised from tap/guest
- * @ws_to_tap:		Window scaling factor advertised to tap/guest
  * @sndbuf:		Sending buffer in kernel, rounded to 2 ^ SNDBUF_BITS
  * @seq_dup_ack_approx:	Last duplicate ACK number sent to tap
- * @faddr:		Guest side forwarding address (guest's remote address)
- * @eport:		Guest side endpoint port (guest's local port)
- * @fport:		Guest side forwarding port (guest's remote port)
  * @wnd_from_tap:	Last window size from tap, unscaled (as received)
  * @wnd_to_tap:		Sending window advertised to tap, unscaled (as sent)
  * @seq_to_tap:		Next sequence for packets to tap
@@ -49,6 +46,10 @@ struct tcp_tap_conn {
 	unsigned int	ws_from_tap	:TCP_WS_BITS;
 	unsigned int	ws_to_tap	:TCP_WS_BITS;
 
+#define TCP_MSS_BITS			14
+	unsigned int	tap_mss		:TCP_MSS_BITS;
+#define MSS_SET(conn, mss)	(conn->tap_mss = (mss >> (16 - TCP_MSS_BITS)))
+#define MSS_GET(conn)		(conn->tap_mss << (16 - TCP_MSS_BITS))
 
 	int		sock		:FD_REF_BITS;
 
@@ -77,13 +78,6 @@ struct tcp_tap_conn {
 #define ACK_TO_TAP_DUE		BIT(3)
 #define ACK_FROM_TAP_DUE	BIT(4)
 
-
-#define TCP_MSS_BITS			14
-	unsigned int	tap_mss		:TCP_MSS_BITS;
-#define MSS_SET(conn, mss)	(conn->tap_mss = (mss >> (16 - TCP_MSS_BITS)))
-#define MSS_GET(conn)		(conn->tap_mss << (16 - TCP_MSS_BITS))
-
-
 #define SNDBUF_BITS		24
 	unsigned int	sndbuf		:SNDBUF_BITS;
 #define SNDBUF_SET(conn, bytes)	(conn->sndbuf = ((bytes) >> (32 - SNDBUF_BITS)))
@@ -91,11 +85,6 @@ struct tcp_tap_conn {
 
 	uint8_t		seq_dup_ack_approx;
 
-
-	union inany_addr faddr;
-	in_port_t	eport;
-	in_port_t	fport;
-
 	uint16_t	wnd_from_tap;
 	uint16_t	wnd_to_tap;
 
@@ -109,22 +98,24 @@ struct tcp_tap_conn {
 /**
  * struct tcp_splice_conn - Descriptor for a spliced TCP connection
  * @f:			Generic flow information
- * @in_epoll:		Is the connection in the epoll set?
  * @s:			File descriptor for sockets
  * @pipe:		File descriptors for pipes
- * @events:		Events observed/actions performed on connection
- * @flags:		Connection flags (attributes, not events)
  * @read:		Bytes read (not fully written to other side in one shot)
  * @written:		Bytes written (not fully written from one other side read)
-*/
+ * @events:		Events observed/actions performed on connection
+ * @flags:		Connection flags (attributes, not events)
+ * @in_epoll:		Is the connection in the epoll set?
+ */
 struct tcp_splice_conn {
 	/* Must be first element */
 	struct flow_common f;
 
-	bool in_epoll	:1;
 	int s[SIDES];
 	int pipe[SIDES][2];
 
+	uint32_t read[SIDES];
+	uint32_t written[SIDES];
+
 	uint8_t events;
 #define SPLICE_CLOSED			0
 #define SPLICE_CONNECT			BIT(0)
@@ -139,8 +130,7 @@ struct tcp_splice_conn {
 #define RCVLOWAT_ACT(sidei_)		((sidei_) ? BIT(4) : BIT(3))
 #define CLOSING				BIT(5)
 
-	uint32_t read[SIDES];
-	uint32_t written[SIDES];
+	bool in_epoll	:1;
 };
 
 /* Socket pools */