arm64 pmap: per-domain pv chunk list

[andrew]

Summary

As with amd64 use a per-domain pv chunk lock to reduce contention as
chunks get created and removed all the time.

[markj]

sys/arm64/arm64/pmap.c

2631

pv_chunks_mutex is no more, so this comment is stale.

2768

This ignores the thread's NUMA allocation policy. In particular, the thread may have been configured to never allocate pages from a particular domain, but here it may do so. I suspect this function should use one of the domainset iterators like vm_page_alloc_noobj() does.

2779

Extra newline.

5505

Can this simply be free_pv_chunk_batch(free_chunks);?

[andrew]

sys/arm64/arm64/pmap.c

2768

This looks like it's also a problem on amd64

[andrew]

• Fix a comment
• Remove an extra newline
• Remove an unneeded cast