Re: [Qemu-devel] [RFC 0/7] Safe watch and breakpoint manipulation

[Paolo Bonzini]

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...

Paolo