On 17/06/16 20:01, Paolo Bonzini wrote: > > On 17/06/2016 18:33, Alex Bennée wrote: >> First we move the break/watchpoints into an array which is more >> amenable to RCU control that the QLIST. We then control the life time >> of references to break/watchpoint data by removing long held >> references in the target code and getting information when needed from >> the core. Then we stop dynamically allocation the watch/breakpoint >> data and store it directly in the array which makes iteration across >> the list a bit more cache friendly than referenced pointers. Finally >> addition and removal of elements of the array is put under RCU >> control. This ensures there is always a safe array of data to check >> in the run-loop. > I'm not sure why you say that arrays are more amenable than QTAILQ > (though indeed include/qemu/rcu_queue.h only includes QLIST for now), > but I feel bad asking you to redo all the work...
Is there any realistic way to manage *doubly* linked lists in RCU? Kind regards, Sergey
