This implements the userspace binding for RingBuf.
Instead of streaming the samples as heap buffers, the process_ring
function takes a callback to which we pass the event's byte region,
roughly following [libbpf]'s API design. This avoids a copy and allows
marking the consumer pointer in a timely manner.
[libbpf]: https://github.com/libbpf/libbpf/blob/master/src/ringbuf.c
Additionally, integration tests are added to demonstrate the usage
of the new APIs and to ensure that they work end-to-end.
Co-authored-by: William Findlay <william@williamfindlay.com>
Co-authored-by: Tatsuyuki Ishi <ishitatsuyuki@gmail.com>
Extract the symlink-to-bpf-linker logic from integration-test to xtask
and use it in a new build script in integration-ebpf, causing ebpf
probes to be rebuilt when bpf-linker changes. Previously bpf-linker
changes would rebuild integration-test, but not integration-ebpf,
resulting in stale tests.
Note that this still doesn't address the possibility that a new
bpf-linker is added to the PATH ahead of the cached one. Solving this in
the general case would require rebuild-if-changed-env=PATH *and*
rebuild-if-changed={every-directory-in-PATH} which would likely mean far
too much cache invalidation.
This change does a few things:
- it fixes a bug in the wrappers, where we were expecting the kernel to
return len=1 for b"\0" where it instead returns 0 and doesn't write
out the NULL terminator
- it makes the helpers more robust by hardcoding bound checks in
assembly so that LLVM optimizations can't transform the checks in a
way that the verifier can't understand.
- it adds integration tests
This commit moves the aya-log projects from the subtree and adds them to
the main cargo workspace. It also brings the BPF crates into the
workspace and moves the macro crates up a level since they aren't BPF
code.
Miri was disabled for aya-bpf as the previous config wasn't actually
checking anything.
CI, clippy, fmt and release configurations have all been adjusted
appropriately.
CI was not properly running for other supported arches which was also
ixed here.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
This commit replaces the existing RTF test runner with a simple rust
binary package called - integration-test.
integration-test depends on integration-ebpf, which contains test eBPF
code written in Rust and C. `cargo xtask build-integration-test-ebpf`
can be used to build this code and supress rust-analyzer warnings. It
does require `bpf-linker`, but that is highly likely to be available to
developers of Aya. It also requires a checkout of `libbpf` to extract
headers like bpf-helpers.h.
Since everything is compiled into a single binary, it can be run
be run locally using `cargo xtask integration-test` or remotely using
`./run.sh` which re-uses the bash script from the old test framework
to spawn a VM in which to run the tests.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Andrew Werner
Tuetuopay
Tamir Duberstein
Dave Tucker
Alessandro Decina
Michal Rostecki
Michal Rostecki