Are BPF maps threadsafe?

Are BPF map operations threadsafe?

```
bpf_map.insert()
bpf_map.increment()
bpf_map->field_1 += value_1
```

Documentation on this matter is scarce. I suspect (3) is not atomic, and if so are there workarounds?

Start by reviewing the documented behavior of the BPF map operations shown: insert(), increment(), and field_1 += value_1. The documentation is complete when it explains their thread safety and atomicity, and identifies any supported workarounds for non-atomic updates.

Written by the indexing model from the issue text.