iproute2-next:tc:action: add a gate control action

Introduce a ingress frame gate control flow action.
Tc gate action does the work like this:
Assume there is a gate allow specified ingress frames can pass at
specific time slot, and also drop at specific time slot. Tc filter
chooses the ingress frames, and tc gate action would specify what slot
does these frames can be passed to device and what time slot would be
dropped.
Tc gate action would provide an entry list to tell how much time gate
keep open and how much time gate keep state close. Gate action also
assign a start time to tell when the entry list start. Then driver would
repeat the gate entry list cyclically.
For the software simulation, gate action require the user assign a time
clock type.

Below is the setting example in user space. Tc filter a stream source ip
address is 192.168.0.20 and gate action own two time slots. One is last
200ms gate open let frame pass another is last 100ms gate close let
frames dropped.

 # tc qdisc add dev eth0 ingress
 # tc filter add dev eth0 parent ffff: protocol ip \

            flower src_ip 192.168.0.20 \
            action gate index 2 clockid CLOCK_TAI \
            sched-entry open 200000000ns -1 8000000b \
            sched-entry close 100000000ns

 # tc chain del dev eth0 ingress chain 0

"sched-entry" follow the name taprio style. Gate state is
"open"/"close". Follow the period nanosecond. Then next -1 is internal
priority value means which ingress queue should put to. "-1" means
wildcard. The last value optional specifies the maximum number of
MSDU octets that are permitted to pass the gate during the specified
time interval, the overlimit frames would be dropped.

Below example shows filtering a stream with destination mac address is
10:00:80:00:00:00 and ip type is ICMP, follow the action gate. The gate
action would run with one close time slot which means always keep close.
The time cycle is total 200000000ns. The base-time would calculate by:

     1357000000000 + (N + 1) * cycletime

When the total value is the future time, it will be the start time.
The cycletime here would be 200000000ns for this case.

 #tc filter add dev eth0 parent ffff:  protocol ip \
           flower skip_hw ip_proto icmp dst_mac 10:00:80:00:00:00 \
           action gate index 12 base-time 1357000000000ns \
           sched-entry CLOSE 200000000ns \
           clockid CLOCK_TAI

Signed-off-by: Po Liu <Po.Liu@nxp.com>
Signed-off-by: David Ahern <dsahern@gmail.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/tc/Makefile b/tc/Makefile
index e31cbc12..79c9c1dd 100644
--- a/tc/Makefile
+++ b/tc/Makefile
@@ -54,6 +54,7 @@ TCMODULES += m_bpf.o
 TCMODULES += m_tunnel_key.o
 TCMODULES += m_sample.o
 TCMODULES += m_ct.o
+TCMODULES += m_gate.o
 TCMODULES += p_ip.o
 TCMODULES += p_ip6.o
 TCMODULES += p_icmp.o