disable sort-on-RX, CPU pinning seems to work for now

udp/udp_linux.go

@@ -430,8 +430,18 @@ func (u *StdConn) listenOutSingle(r EncReader, flush func()) error {
 	}
 }
 
-func (u *StdConn) listenOutBatch(r EncReader, flush func()) error {
+func getFrom(names [][]byte, i int, isV4 bool) netip.AddrPort {
 	var ip netip.Addr
+	// Its ok to skip the ok check here, the slicing is the only error that can occur and it will panic
+	if isV4 {
+		ip, _ = netip.AddrFromSlice(names[i][4:8])
+	} else {
+		ip, _ = netip.AddrFromSlice(names[i][8:24])
+	}
+	return netip.AddrPortFrom(ip.Unmap(), binary.BigEndian.Uint16(names[i][2:4]))
+}
+
+func (u *StdConn) listenOutBatch(r EncReader, flush func()) error {
 	var n int
 	var operr error
 
@@ -476,15 +486,9 @@ func (u *StdConn) listenOutBatch(r EncReader, flush func()) error {
 
 		// Phase 1: gather every segment from this recvmmsg into rxOrder,
 		// splitting GRO superpackets into their constituent segments.
-		u.rxOrder.reset()
+		//todo u.rxOrder.reset()
 		for i := 0; i < n; i++ {
-			// Its ok to skip the ok check here, the slicing is the only error that can occur and it will panic
-			if u.isV4 {
-				ip, _ = netip.AddrFromSlice(names[i][4:8])
-			} else {
-				ip, _ = netip.AddrFromSlice(names[i][8:24])
-			}
-			from := netip.AddrPortFrom(ip.Unmap(), binary.BigEndian.Uint16(names[i][2:4]))
+			from := getFrom(names, i, u.isV4)
 			payload := buffers[i][:msgs[i].Len]
 
 			segSize := 0
@@ -492,17 +496,28 @@ func (u *StdConn) listenOutBatch(r EncReader, flush func()) error {
 			if cmsgSpace > 0 {
 				segSize, outerECN = parseRecvCmsg(&msgs[i].Hdr, u.groSupported, u.ecnRecvSupported, u.isV4)
 			}
-			u.rxOrder.addEntry(from, payload, segSize, outerECN)
+
+			if segSize <= 0 || segSize >= len(payload) {
+				r(from, payload, RxMeta{OuterECN: outerECN})
+			} else {
+				for off := 0; off < len(payload); off += segSize {
+					end := off + segSize
+					if end > len(payload) {
+						end = len(payload)
+					}
+					seg := payload[off:end]
+					r(from, seg, RxMeta{OuterECN: outerECN})
+				}
+			}
+
+			//todo u.rxOrder.addEntry(from, payload, segSize, outerECN)
 		}
 
-		// Phase 2 + 3: stable-sort by (src, port, counter), then deliver in
-		// order. Reorder distance is bounded by len(u.rxOrder.buf), which
-		// stays well within the receiver's ReplayWindow (currently 8192) so
-		// older arrivals are not rejected as replays.
-		u.rxOrder.sortStable()
-		u.rxOrder.deliver(r)
-		// End-of-batch: let callers (e.g. TUN write coalescer) flush any
-		// state they accumulated across this batch.
+		// stable-sort by (src, port, counter), then deliver in order.
+		// this is on top of the sort performed before decrypt
+		//todo u.rxOrder.sortStable()
+		//todo u.rxOrder.deliver(r)
+		// let callers (e.g. TUN write coalescer) flush any state they accumulated across this batch.
 		flush()
 	}
 }