On Mon, Jun 4, 2012 at 6:38 PM, Merlin Moncure <mmoncure@gmail.com> wrote:
> On Mon, Jun 4, 2012 at 10:17 AM, Merlin Moncure <mmoncure@gmail.com> wrote:
>> What happens (in the very unlikely, but possible case?) if another
>> backend races to the buffer you've pointed at with 'victim'? It looks
>> like multiple backends share the clock sweep now, but don't you need
>> to need an extra test to ensure it's still a candidate victim buffer?
>
> Actually, I don't think you do: the existing check on refcount is
> probably good enough. Hm, why did you get rid of
> BufferStrategyControl.lastFreeBuffer?
It was dead code as far as I could tell. That change isn't actually
relevant for this patch because free-list management is still
protected by a lock (except the initial unlocked test that is
doublechecked under lock) and so doesn't need any adjustment.
Ants Aasma
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