Convert consumers to vm_page_alloc_noobj_contig()

[markj]

Summary

Remove now-unneeded page zeroing. No functional change intended.

[• hselasky]

Looks good, assuming zero handling is preserved.

[alc]

sys/amd64/amd64/mp_machdep.c

337

I observe that you eliminated VM_ALLOC_NOBUSY here but not elsewhere. Why?

[markj]

sys/amd64/amd64/mp_machdep.c

337

No good reason. I think it makes sense to simply drop the VM_ALLOC_NOBUSY flag from all callers, as it is already implied by VM_ALLOC_NOOBJ.

[alc]

sys/amd64/amd64/mp_machdep.c

337

I agree.

[markj]

Drop unused VM_ALLOC_NOBUSY from consumers.

[markj]

Drop uses of VM_ALLOC_NORMAL from vm_page_alloc_noobj_contig() and
vm_page_alloc_noobj_contig_domain() callers.

[kib]

sys/arm/nvidia/drm2/tegra_bo.c

105–106

The variable becomes somewhat pointless. You can directly pass _WIRED|_ALLOC_ZERO to vm_page_alloc_noobj_contig(), and vm_page_reclaim_contig() is fine with 0 instead pflags.

[markj]

Drop an unneeded local variable.

[alc]

sys/compat/linuxkpi/common/src/linux_page.c

107–108

Is PAGE_SIZE actually correct? I would guess that Linux guarantees that an order n allocation is aligned to an order n address. That said, at the moment, this is probably not an issue because of the way that vm_phys does contig allocations.

sys/powerpc/aim/mmu_radix.c

3582

Does VM_ALLOC_ZERO actually make sense here?

[markj]

sys/powerpc/aim/mmu_radix.c

3582

It doesn't seem so. I think both of these XXX comments can be resolved by ORing malloc2vm_flags(flags) into req.

[markj]

sys/compat/linuxkpi/common/src/linux_page.c

107–108

I can't find any Linux documentation or code that definitively answers this. Looking at the alloc_pages() implementation, it does seem to return self-aligned runs in practice, but I can't tell if this is a guarantee of the interface. alloc_contig_pages() has a comment stating that self-alignment is guaranteed if the size of the run is a power of 2, but this function is not used much.

[markj]

Use malloc2vm_flags() in radix_pgd_import().