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>
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.
For tests that do networking operations, this allows to have a
clean-state network namespace and interfaces for each test. Mainly, this
avoids "device or resource busy" errors when reusing the loopback
interface across tests.
"integration tests" as defined by Cargo produce a binary per file in the
tests directory. This is really not what we want and has a number of
downsides, but the main one is binary size.
Before:
tamird@pc:~/src/aya$ cargo xtask build-integration-test | xargs ls -lah
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `target/debug/xtask build-integration-test`
Compiling integration-test v0.1.0 (/home/tamird/src/aya/test/integration-test)
Finished dev [unoptimized + debuginfo] target(s) in 0.68s
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/bpf_probe_read-e03eb905a5e6209c
-rwxrwxr-x 1 tamird tamird 35M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/btf_relocations-57a4fbb38bf06064
-rwxrwxr-x 1 tamird tamird 31M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/elf-98b7a32d6d04effb
-rwxrwxr-x 1 tamird tamird 6.9M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/integration_test-0dd55ce96bfdad77
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/load-0718562e85b86d03
-rwxrwxr-x 1 tamird tamird 40M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/log-dbf355f9ea34068a
-rwxrwxr-x 1 tamird tamird 36M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/rbpf-89a1bb848fa5cc3c
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/relocations-cfe655c3bb413d8b
-rwxrwxr-x 1 tamird tamird 34M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/smoke-ccd3974180a3fd29
After:
tamird@pc:~/src/aya$ cargo xtask build-integration-test | xargs ls -lah
Finished dev [unoptimized + debuginfo] target(s) in 0.05s
Running `target/debug/xtask build-integration-test`
Compiling integration-test v0.1.0 (/home/tamird/src/aya/test/integration-test)
Finished dev [unoptimized + debuginfo] target(s) in 0.90s
-rwxrwxr-x 1 tamird tamird 47M Jul 12 15:21 /home/tamird/src/aya/target/debug/deps/integration_test-0dd55ce96bfdad77
Since we plan to run these tests in a VM, copying 10x fewer bytes seems
like a win.
- 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.
This doesn't add any value; use `cargo build --tests` with
`--message-format=json` instead; parse the output using `cargo_metadata`
to discover the location of the test binary.
Move test/integration-test/src/tests -> test/integration-test/tests to
conform to
https://doc.rust-lang.org/book/ch11-03-test-organization.html#integration-tests.
Andrew Werner
Tuetuopay
Tamir Duberstein
Dave Tucker