T210: Review p4c once again (#17)

p4lang · mihaibudiu · Mar 4, 2020 · Apr 8, 2019 · Apr 8, 2019 · Apr 13, 2019
commit 0ca94d36fc7e20d50111bae83f860a5858df49e1
diff --git a/.gitignore b/.gitignore
@@ -36,5 +36,3 @@ build/
 
 # macOS files
 .DS_Store
-
-.idea/*
diff --git a/backends/ubpf/CMakeLists.txt b/backends/ubpf/CMakeLists.txt
@@ -57,10 +57,10 @@ set (P4C_UBPF_DIST_HEADERS p4include/ubpf_model.p4)
 
 add_cpplint_files(${CMAKE_CURRENT_SOURCE_DIR} "$(P4C_UBPF_SOURCES)")
 
-#build_unified(P4C_UBPF_SOURCES ALL)
+build_unified(P4C_UBPF_SOURCES ALL)
 add_executable(p4c-ubpf ${P4C_UBPF_SOURCES})
 target_link_libraries (p4c-ubpf ${P4C_LIBRARIES} ${P4C_LIB_DEPS})
-#add_dependencies(p4c-ubpf genIR frontend)
+add_dependencies(p4c-ubpf genIR frontend)
 
 install (TARGETS p4c-ubpf
         RUNTIME DESTINATION ${P4C_RUNTIME_OUTPUT_DIRECTORY})

diff --git a/backends/ubpf/README.md b/backends/ubpf/README.md
@@ -2,12 +2,14 @@
 
 This repository implements the uBPF (Userspace BPF) backend for the P4 compiler (https://github.com/p4lang/p4c).
 
-The **p4c-ubpf** compiler allows to translate P4 programs into the uBPF programs. We use the uBPF implementation provided by [the ubpf project](https://github.com/iovisor/ubpf). 
+The **p4c-ubpf** compiler allows to translate P4 programs into the uBPF programs. We use the uBPF implementation provided 
+by [the Oko/P4rt-OVS switch](https://github.com/Orange-OpenSource/oko/tree/p4rt-ovs). The Oko's uBPF VM is based on the
+open-source implementation provided by [IOVisor](https://github.com/iovisor/ubpf).
 
 The P4-to-uBPF compiler accepts only the P4_16 programs written for the `ubpf_model.p4` architecture model.
 
 The backend for uBPF is mostly based on [P4-to-eBPF compiler](../ebpf/README.md). In fact, it implements the same concepts, but
-generates the C code, which is compatible with the user-space BPF implementation. 
+generates the C code, which is compatible with the user space BPF implementation. 
 
 ## Background
 
@@ -28,13 +30,12 @@ Apache License, version 2.0.
 
 ## Compiling P4 to uBPF
 
-The scope of the uBPF backend is similar to the scope of the eBPF backend. It means that initially P4-to-uBPF compiler
-supports only simple packet filtering. 
+The scope of the uBPF backend is wider than the scope of the eBPF backend. Except for simple packet filtering the 
+P4-to-uBPF compiler supports also P4 registers and programmable actions including packet's modifications and tunneling. For further details
+refer to [uBPF architecture model](p4include/ubpf_model.p4).
 
-We will continuously work to provide wider range of functionalities for P4-to-uBPF.
-
-The current version of the P4-to-uBPF compiler translaters P4_16 programs to programs written in the C language. This
-program is compatible with the uBPF VM and the clang compiler can be used to generate uBPF bytecode.
+The current version of the P4-to-uBPF compiler translates P4_16 programs to programs written in the C language. This
+program is compatible with the uBPF VM and the `clang` compiler can be used to generate uBPF bytecode.
 
 ### Translation between P4 and C
 
@@ -47,14 +48,15 @@ However, we introduced some modifications, which are listed below:
 * There are user-space data types used (e.g. uint8_t, etc.). 
 * Methods to extract packet fields (e.g. load_dword, etc.) has been re-implemented to use user-space data types.
 * The uBPF helpers are imported into the C programs.
-* We have added `mark_to_drop()` extern to the `ubpfFilter` model, so that packets to drop are marked in the P4-native way.
+* We have added `mark_to_drop()` extern to the `ubpf` model, so that packets to drop are marked in the P4-native way.
+* We have added support for P4 registers implemented as BPF maps
 
 ### How to use?
 
-The sample P4 programs are located in `examples/` directory. We have tested them on the [Oko](https://github.com/Orange-OpenSource/oko) switch - 
+The sample P4 programs are located in `examples/` directory. We have tested them with the [Oko/P4rt-OVS](https://github.com/Orange-OpenSource/oko/tree/p4rt-ovs) switch - 
 the Open vSwitch that can be extended with BPF programs at runtime. See [the detailed tutorial](./docs/EXAMPLES.md) on how to run and test those examples.
 
-The P4 programs for P4-to-uBPF compiler must be written for the `ubpf_filter_model.p4`.
+The P4 programs for P4-to-uBPF compiler must be written for the `ubpf_model.p4`.
 
 In order to generate the C code use the following command:
 

diff --git a/backends/ubpf/codeGen.h b/backends/ubpf/codeGen.h
@@ -9,10 +9,7 @@ namespace UBPF {
     class UbpfCodeBuilder : public EBPF::CodeBuilder {
     public:
         const UbpfTarget *target;
-
-        explicit UbpfCodeBuilder(const UbpfTarget *target) : EBPF::CodeBuilder(target), target(target) {
-
-        }
+        explicit UbpfCodeBuilder(const UbpfTarget *target) : EBPF::CodeBuilder(target), target(target) {}
     };
 }
 

diff --git a/backends/ubpf/docs/EXAMPLES.md b/backends/ubpf/docs/EXAMPLES.md
@@ -1,7 +1,8 @@
 # Introduction
 
 This file contains description of the basic P4 programs, which were used to test the functionality of the P4-to-uBPF compiler.
-All tests have been run on the [Oko](https://github.com/Orange-OpenSource/oko) switch using [Vagrant prepared for Oko](https://github.com/P4-Research/vagrant-oko).
+All tests have been run on the [Oko](https://github.com/Orange-OpenSource/oko/tree/p4rt-ovs) switch.
+You can use [Vagrantfile](../tests/environment/Vagrantfile) to set up a test environment.
 
 Before any experiment the following commands need to be invoked:
 
@@ -48,6 +49,7 @@ This section presents P4 program, which modifies the packet's fields.
 Sample usage:
 
 ```bash
+# Template: ovs-ofctl update-bpf-map <BRIDGE> <PROGRAM-ID> <MAP-ID> key <KEY-DATA> value <VALUE-DATA>
 $ sudo ovs-ofctl update-bpf-map br0 1 0 key 14 0 16 172 value 0 0 0 0 0 0 0 0 0 0 0 0 # decrements MPLS TTL
 $ sudo ovs-ofctl update-bpf-map br0 1 0 key 14 0 16 172 value 1 0 0 0 24 0 0 0 0 0 0 0 # sets MPLS label to 24
 $ sudo ovs-ofctl update-bpf-map br0 1 0 key 14 0 16 172 value 2 0 0 0 24 0 0 0 0 0 0 0 # sets MPLS label to 24 and decrements TTL
@@ -81,15 +83,17 @@ $ sudo ovs-ofctl update-bpf-map br0 1 0 key 254 128 0 0 0 0 0 0 10 0 39 255 254
 
 ## Registers
 
-This section presents P4 programs, which use registers.   
-Register can be declared this way:  
+This section presents P4 programs, which use registers. Register can be declared this way:
+
 `Register<value_type, key_type>(number_of_elements) register_t;`  
-where:  
-`value_type` - is bit array type (i.e. bit<32>) or struct like type  
-`key_type` - is bit array type (i.e. bit<32>) or struct like type  
-`number_of_elements` - the maximum number of key-value pairs
 
-Currently registers have a limitation - they are not being initialized automatically. Initialization has to be done by control plane. 
+The parameters are as follows:
+
+- `value_type` - is bit array type (i.e. bit<32>) or struct like type  
+- `key_type` - is bit array type (i.e. bit<32>) or struct like type  
+- `number_of_elements` - the maximum number of key-value pairs
+
+Currently registers have a limitation - they are not being initialized with default values. Initialization has to be done by a control plane. 
 
 ### Rate limiter (rate-limiter.p4)
 
@@ -102,20 +106,24 @@ It means that 10 packets are passed in 100 ms window. It also means 100 packets
 If you send 1470 Bytes width packets the bit rate should not exceed 1.176 Mbit/s (1470B * 8 * (10/100ms)).
 
 Due to registers limitation before starting your own tests initialize rate limiter registers with zeros:
+
 ```bash
 # Initalizes timestamp_r register
 $ sudo ovs-ofctl update-bpf-map br0 1 0 key 0 0 0 0 value 0 0 0 0
 # Initalizes count_r register
 $ sudo ovs-ofctl update-bpf-map br0 1 1 key 0 0 0 0 value 0 0 0 0
 ```
 
-For measuring the bandwidth use for instance iperf tool:  
+To measure the bandwidth use the `iperf` tool:  
 
 Start a iperf UDP server
+
 ```bash
 $ iperf -s -u
 ```
-Then run iperf client
+
+Then, run `iperf` client:
+
 ```bash
 $ iperf -c <server_ip> -b 10M -l 1470
 ```
@@ -152,6 +160,7 @@ This section presents more complex examples of packet tunneling operations. Ther
 To run example compile `vxlan.p4` with `p4c` and then `clang-6.0`. 
 
 Sample usage:
+
 ```bash
 # Sets action vxlan_decap() (value 0) for packets matching rule VNI=25 (key 25) 
 # handled by the table upstream_tbl (map id 0) and BPF prog 1.
@@ -166,15 +175,17 @@ sudo ovs-ofctl update-bpf-map br0 1 1 key 14 0 16 172 value 0 0 0 0
 To run example compile `gtp.p4` with `p4c` and then `clang-6.0`. 
 
 To test encapsulation:
+
 ```bash
 # For downstream_tbl (ID 1) sets action gtp_encap() (value 0) and GTP TEID=3 for packets with destination IP address 172.16.0.14.
-$ sudo ovs-ofctl update-bpf-map br0 10 1 key 14 0 16 172 value 0 0 0 0 3 0 0 0
+$ sudo ovs-ofctl update-bpf-map br0 1 1 key 14 0 16 172 value 0 0 0 0 3 0 0 0
 ```
 
 To test decapsulation:
+
 ```bash
 # For upstream_tbl (ID 0) sets action gtp_decap() for packets matching GTP TEID=3.
-$ sudo ovs-ofctl update-bpf-map br0 10 0 key 3 0 0 0 value 0 0 0 0
+$ sudo ovs-ofctl update-bpf-map br0 1 0 key 3 0 0 0 value 0 0 0 0
 ```
 
 Scapy can be used to easily test GTP protocol:

diff --git a/backends/ubpf/examples/gtp.p4 b/backends/ubpf/examples/gtp.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/metadata.p4 b/backends/ubpf/examples/metadata.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include <core.p4>
 #include "ubpf_model.p4"
 

diff --git a/backends/ubpf/examples/mpls.p4 b/backends/ubpf/examples/mpls.p4
diff --git a/backends/ubpf/examples/oko-test-actions.p4 b/backends/ubpf/examples/oko-test-actions.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/oko-test-ipv6.p4 b/backends/ubpf/examples/oko-test-ipv6.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/rate-limiter-structs.p4 b/backends/ubpf/examples/rate-limiter-structs.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/rate-limiter.p4 b/backends/ubpf/examples/rate-limiter.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/simple-firewall.p4 b/backends/ubpf/examples/simple-firewall.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/tunneling.p4 b/backends/ubpf/examples/tunneling.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/examples/vxlan.p4 b/backends/ubpf/examples/vxlan.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #include "ubpf_model.p4"
 #include <core.p4>
 

diff --git a/backends/ubpf/p4include/ubpf_model.p4 b/backends/ubpf/p4include/ubpf_model.p4
@@ -1,3 +1,19 @@
+/*
+Copyright 2019 Orange
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
 #ifndef _FILTER_MODEL_P4_
 #define _FILTER_MODEL_P4_
Original file line number	Diff line number	Diff line change
Expand Up		@@ -36,5 +36,3 @@ build/

		# macOS files
		.DS_Store

		.idea/*