configs: Enable TRANSPARENT_HUGEPAGE_MADVISE

[popcornmix]

Upstream v3d patches are adding support for big (64K) and super (1MB) pages, which require these options.

See:
https://lore.kernel.org/dri-devel/20240923141348.2422499-1-mcanal@igalia.com/

There are also some potential performance benefits linked from:
#6297

[popcornmix]

Putting this up as a draft PR, so it's not forgotten.
We won't get the v3d benefits until we backport them to 6.6, or switch to a newer upstream kernel.

My brief testing suggests TRANSPARENT_HUGEPAGE_MADVISE doesn't have performance hit on NUMA that TRANSPARENT_HUGEPAGE_ALWAYS did, but perhaps wait until NUMA is more final (and we don't spot any other adverse results) before merging this.

[satmandu]

Current testing kernels from the rpi-firmware repo now show this in the dmesg:

[   16.662538] bcm2835_isp: module is from the staging directory, the quality is unknown, you have been warned.
[   16.678470] v3d fec00000.v3d: [drm] Transparent Hugepage support is recommended for optimal performance on this platform!
[   16.688136] [drm] Initialized v3d 1.0.0 for fec00000.v3d on minor 0

[popcornmix]

Yes. A todo is to profile various use cases, including v3d and check what the benefits are, and if any negatives are observed.

Based on the testing TRANSPARENT_HUGEPAGE_MADVISE may well be enabled in future.

We're happy to heard of any positive (or negative) effects from users.

[flatsiedatsie]

I spotted a warning in journalctl on a Raspberry Pi OS Trixie system which lead me here (via #7076).

[    5.784701] v3d fec00000.v3d: [drm] Transparent Hugepage support is recommended for optimal performance on this platform!

[mairacanal]

The newest version of the PR is #7285