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>
The struct_flavors test previously expected the same thing with and
without relocations. It now expects different values.
Also rename an enum variant "u64" to "S64". This was a typo. Turns out
that U32 is a type that exists in kernel headers, so all enum values are
suffixed with "_VAL".
Remove stdlib.h and the call to exit(). This alone makes the test fail
with a poisoned relocation. Bringing over the map definition makes the
test work again.
This commit fixes the (func|line)_info when we have multiple programs in
the same section. The integration test reloc.bpf.c serves as our test
case here. This required filtering down the (func|line)_info to only
that in scope of the current symbol + then adjusting the offets to
appease the kernel.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
Move the use of clang and llvm-objcopy from run-time to build-time. This
allows the integration tests to run on VMs with simpler userlands.
Create a new CI job to build the integration tests separately from
running them. Ship them from that job to the runner job using github
actions artifacts.
This makes a few changes to the way that Aya reads the ELF object
files.
1. To find programs in a section, we use the symbols table. This allows
for cases where multiple programs could appear in the same section.
2. When parsing our ELF file we build symbols_by_section_index as an
optimization as we use it for legacy maps, BTF maps and now programs.
As a result of theses changes the "NAME" used in `bpf.prog_mut("NAME")`
is now ALWAYS the same as the function name in the eBPF code, making the
user experience more consistent.
Signed-off-by: Dave Tucker <dave@dtucker.co.uk>
- Add libbpf as a submodule. This prevents having to plumb its location
around (which can't be passed to Cargo build scripts) and also
controls the version against which codegen has run.
- Move bpf written in C to the integration-test crate and define
constants for each probe.
- Remove magic; each C source file must be directly enumerated in the
build script and in lib.rs.
Andrew Werner
Tamir Duberstein
Dave Tucker