On Tue, Mar 28, 2023 at 3:01 PM Chris Li <chrisl@xxxxxxxxxx> wrote: > > On Tue, Mar 28, 2023 at 02:44:27PM -0700, Yosry Ahmed wrote: > > > Your swap descriptor will be using one swp_entry_t, which get from the PTE > > > to lookup, right? That is the swap entry I am talking about. You just > > > substitute zswap swap entry with the swap descriptor swap entry. > > > You still need to allocate from the free swap entry space at least once. > > > > Oh, you mean the swap ID space. We just need to find an unused ID, we > > can simply use an allocating xarray > > (https://docs.kernel.org/core-api/xarray.html#allocating-xarrays). > > This is simpler than keeping track of swap slots in a swapfile. > > Ah I see. That makes sense. Thanks for explaining it to me. > > The real block swap device will still need to scan the swap_map > to find an empty space to write the page. Yes, exactly. It's a tradeoff, and I think as long as whatever we decide can be considered as a step towards the right direction it should be fine. > > Chris > >
