On Wed, Sep 04, 2024 at 05:35:49PM GMT, Matthew Wilcox wrote: > On Wed, Sep 04, 2024 at 09:18:01AM -0700, Suren Baghdasaryan wrote: > > I'm not sure I understand your suggestion, Matthew. We allocate a > > folio and need to store a reference to the tag associated with the > > code that allocated that folio. We are not operating with ranges here. > > Are you suggesting to use a maple tree instead of page_ext to store > > this reference? > > I'm saying that a folio has a physical address. So you can use a physical > address as an index into a maple tree to store additional information > instead of using page_ext or trying to hammer the additional information > into struct page somewhere. Ah, thanks, that makes more sense. But it would add a lot of overhead to the page alloc/free paths...