[dpdk-dev] [PATCH v1 0/5] add framework to load and execute BPF code
Konstantin Ananyev
konstantin.ananyev at intel.com
Fri Mar 9 17:42:00 CET 2018
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.
...
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
If you are curious to check JIT generated native code:
gdb -p `pgrep testpmd`
(gdb) disas 0x7fd173c5f000,+76
Dump of assembler code from 0x7fd173c5f000 to 0x7fd173c5f04c:
0x00007fd173c5f000: mov %rdi,%rsi
0x00007fd173c5f003: movzwq 0x10(%rsi),%rdi
0x00007fd173c5f008: mov 0x0(%rsi),%rdx
0x00007fd173c5f00c: add %rdi,%rdx
0x00007fd173c5f00f: movzbq 0xc(%rdx),%rdi
0x00007fd173c5f014: movzbq 0xd(%rdx),%rdx
0x00007fd173c5f019: shl $0x8,%rdx
0x00007fd173c5f01d: or %rdi,%rdx
0x00007fd173c5f020: cmp $0x608,%rdx
0x00007fd173c5f027: jne 0x7fd173c5f044
0x00007fd173c5f029: mov $0xb712e8,%rdi
0x00007fd173c5f030: mov 0x0(%rdi),%rdi
0x00007fd173c5f034: mov $0x40,%rdx
0x00007fd173c5f03b: mov $0x4db2f0,%rax
0x00007fd173c5f042: callq *%rax
0x00007fd173c5f044: mov $0x1,%rax
0x00007fd173c5f04b: retq
End of assembler dump.
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
TODO list:
==========
- meson build
- UT for it
- implement proper validate()
- allow JIT to generate bulk version
- FreeBSD support
Not currently supported features:
=================================
- cBPF
- tail-pointer call
- eBPF MAP
- JIT for non X86_64 targets
- skb
Konstantin Ananyev (5):
bpf: add BPF loading and execution framework
bpf: add JIT compilation for x86_64 ISA.
bpf: introduce basic RX/TX BPF filters
testpmd: new commands to load/unload BPF filters
test: add few eBPF samples
app/test-pmd/bpf_sup.h | 25 +
app/test-pmd/cmdline.c | 146 ++++
config/common_base | 5 +
config/common_linuxapp | 1 +
lib/Makefile | 2 +
lib/librte_bpf/Makefile | 35 +
lib/librte_bpf/bpf.c | 52 ++
lib/librte_bpf/bpf_exec.c | 452 ++++++++++++
lib/librte_bpf/bpf_impl.h | 37 +
lib/librte_bpf/bpf_jit_x86.c | 1329 ++++++++++++++++++++++++++++++++++++
lib/librte_bpf/bpf_load.c | 380 +++++++++++
lib/librte_bpf/bpf_pkt.c | 524 ++++++++++++++
lib/librte_bpf/bpf_validate.c | 55 ++
lib/librte_bpf/rte_bpf.h | 158 +++++
lib/librte_bpf/rte_bpf_ethdev.h | 50 ++
lib/librte_bpf/rte_bpf_version.map | 16 +
mk/rte.app.mk | 2 +
test/bpf/dummy.c | 20 +
test/bpf/mbuf.h | 556 +++++++++++++++
test/bpf/t1.c | 53 ++
test/bpf/t2.c | 30 +
test/bpf/t3.c | 36 +
22 files changed, 3964 insertions(+)
create mode 100644 app/test-pmd/bpf_sup.h
create mode 100644 lib/librte_bpf/Makefile
create mode 100644 lib/librte_bpf/bpf.c
create mode 100644 lib/librte_bpf/bpf_exec.c
create mode 100644 lib/librte_bpf/bpf_impl.h
create mode 100644 lib/librte_bpf/bpf_jit_x86.c
create mode 100644 lib/librte_bpf/bpf_load.c
create mode 100644 lib/librte_bpf/bpf_pkt.c
create mode 100644 lib/librte_bpf/bpf_validate.c
create mode 100644 lib/librte_bpf/rte_bpf.h
create mode 100644 lib/librte_bpf/rte_bpf_ethdev.h
create mode 100644 lib/librte_bpf/rte_bpf_version.map
create mode 100644 test/bpf/dummy.c
create mode 100644 test/bpf/mbuf.h
create mode 100644 test/bpf/t1.c
create mode 100644 test/bpf/t2.c
create mode 100644 test/bpf/t3.c
--
2.13.6
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