> OTOH, there is no reason why we need to disable preemption over that > page_fault_disabled() region. There are code pathes which really do > not require to disable preemption for that. > > We have that seperated in preempt-rt for obvious reasons and IIRC > Peter Zijlstra tried to distangle it in mainline some time ago. I > forgot why that never got merged. > Of course, we can completely separate that in our page fault code by doing pagefault_disabled() checks instead of in_atomic() checks (even in add on patches later). > We tie way too much stuff on the preemption count already, which is a > mightmare because we have no clear distinction of protection > scopes. Although it might not be optimal, but keeping a separate counter for pagefault_disable() as part of the preemption counter seems to be the only doable thing right now. I am not sure if a completely separated counter is even possible, increasing the size of thread_info. I am working on a prototype right now. Thanks! > > Thanks, > > tglx > -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
