On Sat, 2019-04-06 at 15:36 -0400, Mikulas Patocka wrote: > Parisc uses a global spinlock to protect pagetable updates in the TLB > fault handlers. When multiple cores are taking TLB faults > simultaneously, the cache line containing the spinlock becomes a > bottleneck. You can't do this. As the comment in cache.c says: the lock is to protect the merced bus, which runs between the CPUs on some systems. That means it must be a single, global lock. Of course, on systems without a merced bus, we don't need the lock at all, so runtime patching might be usable to fix that case. James
