Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 30 insertions, 0 deletions

diff --git a/kernel/Documentation/networking/tc-actions-env-rules.txt b/kernel/Documentation/networking/tc-actions-env-rules.txt
new file mode 100644
index 000000000..70d6cf608
--- /dev/null
+++ b/kernel/Documentation/networking/tc-actions-env-rules.txt
@@ -0,0 +1,30 @@
+
+The "environmental" rules for authors of any new tc actions are:
+
+1) If you stealeth or borroweth any packet thou shalt be branching
+from the righteous path and thou shalt cloneth.
+
+For example if your action queues a packet to be processed later,
+or intentionally branches by redirecting a packet, then you need to
+clone the packet.
+
+There are certain fields in the skb tc_verd that need to be reset so we
+avoid loops, etc.  A few are generic enough that skb_act_clone()
+resets them for you, so invoke skb_act_clone() rather than skb_clone().
+
+2) If you munge any packet thou shalt call pskb_expand_head in the case
+someone else is referencing the skb. After that you "own" the skb.
+You must also tell us if it is ok to munge the packet (TC_OK2MUNGE),
+this way any action downstream can stomp on the packet.
+
+3) Dropping packets you don't own is a no-no. You simply return
+TC_ACT_SHOT to the caller and they will drop it.
+
+The "environmental" rules for callers of actions (qdiscs etc) are:
+
+*) Thou art responsible for freeing anything returned as being
+TC_ACT_SHOT/STOLEN/QUEUED. If none of TC_ACT_SHOT/STOLEN/QUEUED is
+returned, then all is great and you don't need to do anything.
+
+Post on netdev if something is unclear.
+