Hi Jerin, > > > > BPF is used quite intensively inside Linux (and BSD) kernels > > for various different purposes and proved to be extremely useful. > > > > BPF inside DPDK might also be used in a lot of places > > for a lot of similar things. > > As an example to: > > - packet filtering/tracing (aka tcpdump) > > - packet classification > > - statistics collection > > - HW/PMD live-system debugging/prototyping - trace HW descriptors, > > internal PMD SW state, etc. > > - Comeup with your own idea > > > > All of that in a dynamic, user-defined and extensible manner. > > > > So these series introduce new library - librte_bpf. > > librte_bpf provides API to load and execute BPF bytecode within > > user-space dpdk app. > > It supports basic set of features from eBPF spec. > > Also it introduces basic framework to load/unload BPF-based filters > > on eth devices (right now via SW RX/TX callbacks). > > > > How to try it: > > =============== > > > > 1) run testpmd as usual and start your favorite forwarding case. > > 2) build bpf program you'd like to load > > (you'll need clang v3.7 or above): > > $ cd test/bpf > > $ clang -O2 -target bpf -c t1.c > > > > 3) load bpf program(s): > > testpmd> bpf-load rx|tx <portid> <queueid> <load-flags> <bpf-prog-filename> > > > > <load-flags>: [-][J][M] > > J - use JIT generated native code, otherwise BPF interpreter will be used. > > M - assume input parameter is a pointer to rte_mbuf, > > otherwise assume it is a pointer to first segment's data. > > > > Few examples: > > > > # to load (not JITed) dummy.o at TX queue 0, port 0: > > testpmd> bpf-load tx 0 0 - ./dpdk.org/test/bpf/dummy.o > > #to load (and JIT compile) t1.o at RX queue 0, port 1: > > testpmd> bpf-load rx 1 0 J ./dpdk.org/test/bpf/t1.o > > > > #to load and JIT t3.o (note that it expects mbuf as an input): > > testpmd> bpf-load rx 2 0 JM ./dpdk.org/test/bpf/t3.o > > > > 4) observe changed traffic behavior > > Let say with the examples above: > > - dummy.o does literally nothing, so no changes should be here, > > except some possible slowdown. > > - t1.o - should force to drop all packets that doesn't match: > > 'dst 1.2.3.4 && udp && dst port 5000' filter. > > - t3.o - should dump to stdout ARP packets. > > > > 5) unload some or all bpf programs: > > testpmd> bpf-unload tx 0 0 > > > > 6) continue with step 3) or exit > > > > Not currently supported features: > > ================================= > > - cBPF > > - tail-pointer call > > - eBPF MAP > > - JIT for non X86_64 targets > > May be for next release, we are planning to add arm64 JIT support.
Sounds great :) > Just wondering, How do you test all EBPF opcodes in JIT/Interpreter mode? > Are you planning to add any UT like linux kernel in dpdk ? or it was > similar to https://github.com/iovisor/ubpf/tree/master/tests ? I added UT for it in v3: http://dpdk.org/dev/patchwork/patch/37456/ But it doesn't cover whole ISA yet. In fact - that's what I am working right now - adding more test-cases to it, so hopefully by next release will have much better test coverage. Another thing I plan to add - harden validate() to catch more cases with Invalid code. Konstantin > > Just asking because, when we introduce arm64 JIT support similar > test cases should be required to verify the implementation.
