On Tue, Jan 25, 2022 at 01:23:21PM +0000, Matthew Wilcox wrote: > On Tue, Jan 25, 2022 at 02:42:12PM +0300, Kirill A. Shutemov wrote: > > I wounder if we can get away with zero-API here: we can transparently > > create/use shared page tables for any inode on mmap(MAP_SHARED) as long as > > size and alignment is sutiable. Page tables will be linked to the inode > > and will be freed when the last of such mapping will go away. I don't see > > a need in new syscalls of flags to existing one. > > That's how HugeTLBfs works today, right? Would you want that mechanism > hoisted into the real MM? Because my plan was the opposite -- remove it > from the shadow MM once mshare() is established. I hate HugeTLBfs because it is a special place with own rules. mshare() as it proposed creates a new special place. I don't like this. It's better to find a way to integrate the feature natively into core-mm and make as much users as possible to benefit from it. I think zero-API approach (plus madvise() hints to tweak it) is worth considering. -- Kirill A. Shutemov
