Numerous "MM" Improvements Land In Linux 5.19

Andrew Morton with his recent shift to a Git-based workflow rather than maintaining long patch series has sent in all of the memory management "mm" changes for the Linux 5.19 merge window.

As usual, the "mm" changes collected by Morton span a wide range of work. For Linux 5.19 some of the highlights from this pull include:

- Memcg accounting for Zswap. Currently applications can escape their cgroup memory containment when Zswap is enabled. But now with Linux 5.19 is per-cgroup tracking and limiting of Zswap back-end memory to address this prior oversight.

- Improvements to the SWAP over NFS handling and more broadly various swap-via-file-system enhancements.

- DAMON as the Data Access Monitoring framework developed by Amazon there is now support for online tuning. Up to now configuring DAMON via sysfs hasn't provided a way to adjust the DAMON input parameters while running and thus required stopping/starting DAMON. In turn the DAMON restarts flushes all of the accumulated monitoring results so instead there is now support for online updating of inputs via sysfs.

- Adding the "hugetlb_optimize_vmemmap" sysctl know for online/run-time enabling/toggling of the huge page vmemmap optimization. Thus cuts down on possible downtime for rebooting the server to enabling this memory optimization or for selectively toggling hugetlb_optimize_vmemmap during run-time depending upon the workloads/applications.

This pull request goes over all of the other Linux 5.19 memory management related changes so far for this first week of the merge window.