Refactor ebpf_ring_buffer to remove lock #4204
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- eBPF ring buffer map has not been updated yet.
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Remove lock from ebpf_ring_buffer and use acquire/release and atomics to ensure safe ordering.
Description
The ring buffer now uses acquire/release semantics to synchronize between producers and consumers, and an interlocked compare-exchange to serialize producer reservations.
This change also updates the record header to match the 64 bit header used on linux.
There is no effect on the public API (the implementation details aren't currently exposed by libbpf).
The new producer and consumer algorithms are described in docs/RingBuffer.md and libs/runtime/ebpf_ring_buffer.c.
Testing
Updated existing ring buffer tests and added new stress tests to test the synchronization changes.
Documentation
The new producer and consumer algorithms are described in docs/RingBuffer.md.
The implementation details are documented in libs/runtime/ebpf_ring_buffer.c.
Installation
N/A