Being able to compile the eBPF crates for the host architecture is
useful because it allows `cargo build` and `cargo test` to "just work".
To achieve that, we feature-gate `no_std` and `no_main` on the bpf
target architecture.
Working with aya in vscode will currently show a number of warnings
along the lines of:
```
found duplicate lang item `panic_impl`
the lang item is first defined in crate `std` (which `aya` depends on)
...
second definition in the local crate (`bpf_probe_read`)
```
This comes from feature unification.
integration-test requires the integration-common user feature, which
requires aya, which in turn brings in std.
For this same reason we avoid running clippy across the whole workspace.
We can avoid this issue by using the panic handler from the another
crate, which implements the same loop {} panic handler we use today.
It seems rustc is happy to conditionally link the panic handler
from an external crate without issuing warnings.
Therefore, we add our own crate - ebpf-panic - for this purpose.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
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>
Thomas Eizinger
Dave Tucker
Tamir Duberstein
Andrew Werner