Deprecate all async IO based ring buffer APIs

[shankarseal]

Since ebpf-for-windows now supports the polling model for perf event array and ring buffers, consider marking the following as deprecated.

• ebpf_perf_buffer__new
• ebpf_ring_buffer__new
• ebpf_perf_event_array_map_write
• ebpf_ring_buffer_map_write

Proposed Solution

Mark EBPF_RINGBUF_FLAG_AUTO_CALLBACK and EBPF_PERFBUF_FLAG_AUTO_CALLBACK as deprecated for eventual removal

[dthaler]

Are there existing users or is this just cleaning up code that no one uses? Is there still value in the async apis? E.g., are they more efficient than sync?

[shankarseal]

Are there existing users or is this just cleaning up code that no one uses? Is there still value in the async apis? E.g., are they more efficient than sync?

There is no performance difference between the two approaches. The polling model is what Linux uses, and is arguably less prone to race conditions.