On 12/20/19 4:51 PM, Dan Williams wrote: > On Fri, Dec 20, 2019 at 4:41 PM John Hubbard <jhubbard@xxxxxxxxxx> wrote: >> >> On 12/20/19 4:33 PM, Dan Williams wrote: >> ... >>>> I believe there might be also a different solution for this: For >>>> transparent huge pages, we could find a space in 'struct page' of the >>>> second page in the huge page for proper pin counter and just account pins >>>> there so we'd have full width of 32-bits for it. >>> >>> That would require THP accounting for dax pages. It is something that >>> was probably going to be needed, but this would seem to force the >>> issue. >>> >> >> Thanks for mentioning that, it wasn't obvious to me yet. >> >> How easy is it for mere mortals outside of Intel, to set up a DAX (nvdimm?) >> test setup? I'd hate to go into this without having that coverage up >> and running. It's been sketchy enough as it is. :) > > You too can have the power of the gods for the low low price of a > kernel command line parameter, or a qemu setup. > > Details here: > > https://nvdimm.wiki.kernel.org/how_to_choose_the_correct_memmap_kernel_parameter_for_pmem_on_your_system > https://nvdimm.wiki.kernel.org/pmem_in_qemu > Sweeeet! Now I can really cause some damage. :) thanks, -- John Hubbard NVIDIA
