p4c ebpf backend

[Arishbiswas]

can anyone share me the source code of p4 that can be translated to ebpf code using ebpf_model.p4 architecture . As i am new to this area and dont have much idea about it, it will be really helpful . Thanks in advance!!

[AdarshRawat1]

You can try any program from testdata/p4_16_samples/ *_ebpf.p4

[fruffy]

Correct, the tests are collected here in CMake: https://github.com/p4lang/p4c/blob/main/backends/ebpf/CMakeLists.txt#L178

You can run a test like this:

backends/ebpf/run-ebpf-test.py -t kernel -c "build/p4c-ebpf" /mnt/storage/Projekte/gauntlet/modules/p4c  "$@" testdata/p4_16_samples/action_call_table_ebpf.p4

under the hood this script invokes

p4c/build/p4c-ebpf --Werror -I./p4include --target kernel -o build/tmpfolder/test.c testdata/p4_16_samples/action_call_table_ebpf.p4

Note that you need the appropriate kernel version and the dependencies listed in the eBPF back end in order to make this work.

[Arishbiswas]

thanks for responding
i have one more issue, while trying to run the test-cases for p4tc samples with tc backend then i got the following errors, can you please help me how to resolve it .

/usr/share/p4c/p4include/tc/pna.p4(871): [--Werror=type-error] error: package PNA_NIC
package PNA_NIC<MH, MM>(
^^^^^^^
---- Actual error:
add.p4(113): Cannot unify 'inout' parameter 'hdr' with 'in' parameter 'main_hdr' because they have different directions
inout headers_t hdr, // from main control
^^^
/usr/share/p4c/p4include/tc/pna.p4(867)
in MH main_hdr,
^^^^^^^^
---- Originating from:
add.p4(127): Type of argument 'MainDeparserImpl' (control MainDeparserImpl) does not match type of parameter 'main_deparser' (control MainDeparserT<...>)
MainDeparserImpl()
^^^^^^^^^^^^^^^^^^
add.p4(111)
control MainDeparserImpl(
^^^^^^^^^^^^^^^^
/usr/share/p4c/p4include/tc/pna.p4(874)
MainDeparserT<MH, MM> main_deparser);
^^^^^^^^^^^^^
/usr/share/p4c/p4include/tc/pna.p4(874)
MainDeparserT<MH, MM> main_deparser);
^^^^^^^^^^^^^^^^^^^^^
---- Originating from:
add.p4(128): Constructor invocation '' does not match declaration 'PNA_NIC'
) main;

[fruffy]

You need a different compiler for this. Likely p4c-pna-p4tc instead.