On Sat, Oct 05, 2024 at 09:56:24AM -0700, Linus Torvalds wrote: > On Sat, 5 Oct 2024 at 09:16, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote: > > > > On Wed, Oct 02, 2024 at 10:39:15AM -0700, Linus Torvalds wrote: > > > So I think the real issue is that "active_mm" is an old hack from a > > > bygone era when we didn't have the (much more involved) full TLB > > > tracking. > > > > I still seem to have these patches that neither Andy nor I ever managed > > to find time to finish: > > > > https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/log/?h=x86/lazy > > Yes, that looks very much like what I had in mind. > > In fact, it looks a lot smaller and simpler than what my mental model was. > > I was thinking I'd do it by removing "active_mm" entirely from 'struct > task_struct', and turn it into a per-cpu variable instead, and then > try to massage that into some global new world order. That patch > series you point to seems to be much simpler and clearer. > > Of course, you also say "never managed to finish", so presumably > there's something completely broken in that series, and it doesn't > actually work? Last time I tried it, it worked fine. I just didn't get around to actually fully thinking it trough and making sure nothing subtle was broken etc. Pesky details and such..
