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For example, CXL memory > extents can be 256MB with a matching alignment. If this size/alignment > is smaller than the block size, it can result in stranded capacity. > > Implement memory_block_advise_max_size for use prior to allocator init, > for software to advise the system on the max block size. > > Implement memory_block_probe_max_size for use by arch init code to > calculate the best block size. Use of advice is architecture defined. > > The probe value can never change after first probe. Calls to advise > after probe will return -EBUSY to aid debugging. > > On systems without hotplug, always return -ENODEV and 0 respectively. Should the advice just succeed when the result does not matter? Otherwise, it depends on the caller to not care based on config. I do not feel that strongly about it, so either way: Acked-by: Dan Williams