Change Details

This patch refactors the UMA small alloc code and removes most UMA machine-dependent code. The existing machine-dependent small_alloc code was almost identical across all architectures, except for `powerpc` where using the direct map addresses involved extra steps in some cases. The MI/MD split was replaced by a `__weak_symbol`'d default implementation for fetching direct map addresses (`uma_{dmap_to_vm_page, vm_page_to_dmap}`) that can be overridden by architecture-specific code if need be. Furthermore, `UMA_MD_SMALL_ALLOC` was renamed to `UMA_USE_DMAP`.

This patch refactors the UMA small alloc code and removes most UMA machine-dependent code. The existing machine-dependent small_alloc code was almost identical across all architectures, except for `powerpc` where using the direct map addresses involved extra steps in some cases. The MI/MD split was replaced by a default implementation for fetching direct map addresses (`uma_{dmap_to_vm_page, vm_page_to_dmap}`) that can be overridden by architecture-specific code by defining the `UMA_MD_DMAP_HOOK` symbol. Furthermore, `UMA_MD_SMALL_ALLOC` was renamed to `UMA_USE_DMAP`.

This patch refactors the UMA small alloc code and removes most UMA machine-dependent code. The existing machine-dependent small_alloc code was almost identical across all architectures, except for `powerpc` where using the direct map addresses involved extra steps in some cases. The MI/MD split was replaced by a `__weak_symbol`'d default implementation for fetching direct map addresses (`uma_{dmap_to_vm_page, vm_page_to_dmap}`) that can be overridden by architecture-specific code if need beby defining the `UMA_MD_DMAP_HOOK` symbol. Furthermore, `UMA_MD_SMALL_ALLOC` was renamed to `UMA_USE_DMAP`.