[TCP/DCCP]: Introduce net_xmit_eval

[mirror_ubuntu-artful-kernel.git] / include / linux / netdevice.h

diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 4e967b2e22cc5b7c4126802aebad6b9712492117..caa3c2593719215ca4dc5a431b7adaeb0be62b98 100644 (file)
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -66,6 +66,10 @@ struct netpoll_info;
 #define NET_RX_CN_HIGH         4   /* The storm is here */
 #define NET_RX_BAD             5  /* packet dropped due to kernel error */
 
+/* NET_XMIT_CN is special. It does not guarantee that this packet is lost. It
+ * indicates that the device will soon be dropping packets, or already drops
+ * some packets of the same priority; prompting us to send less aggressively. */
+#define net_xmit_eval(e)       ((e) == NET_XMIT_CN? 0 : (e))
 #define net_xmit_errno(e)      ((e) != NET_XMIT_CN ? -ENOBUFS : 0)
 
 #endif