Re: [Qemu-devel] [PATCH v2 3/5] qemu-queue: drop QCIRCLEQ

[Peter Maydell]

On 13 January 2012 16:34, Paolo Bonzini <address@hidden> wrote:
> The main advantage of circular lists (the fact that the head node
> has the same memory layout as any other node) is completely negated
> by the implementation in qemu-queue.h.  Not surprisingly, nobody
> uses QCIRCLEQ.  While this might change if RCU is ever adopted by
> QEMU, the QLIST is also RCU-friendly and in fact it is used in a
> RCU-like manner by 9pfs already.  So, just kill QCIRCLEQ.

Kirk McKusick on why CIRCLEQ existed in the first place and
why BSD still has it:
http://markmail.org/message/i5oir4jhmkopjzy5
...basically just legacy back-compat. So it's fine for us to drop
it from QEMU, since we have nothing to be back-compat with.

-- PMM