On Mon, 11 Nov 2024 15:19:22 -0800 Suren Baghdasaryan <surenb@xxxxxxxxxx> wrote: > On Mon, Nov 11, 2024 at 2:18 PM Davidlohr Bueso <dave@xxxxxxxxxxxx> wrote: > > > > On Mon, 11 Nov 2024, Suren Baghdasaryan wrote: > > > > >To minimize memory overhead, vm_lock implementation is changed from > > >using rw_semaphore (40 bytes) to an atomic (8 bytes) and several > > >vm_area_struct members are moved into the last cacheline, resulting > > >in a less fragmented structure: > > > > I am not a fan of building a custom lock, replacing a standard one. > > Understandable. If we're going to invent a new lock type, I'm thinking we should do that - make it a standaline thing, add full lockdep support, etc. I wonder if we could remove the lock from the vma altogeher and use an old-fashioned hashed lock. An array of locks indexed by the vma address. It might work well enough, although sizing the array would be difficult.
