[PATCH 2/*] Expand arena_get macro.

[Siddhesh Poyarekar]

On Wed, Dec 11, 2013 at 12:39:16PM +0100, Ondřej Bílka wrote:
> Hi,
> 
> For thread local caches we would need to distinguish arena data from
> thread data. As this access was hidden in arena_get macro we expand it.

I'm not sure I understand why.  Could you elaborate?  There may be a
case for consolidating those macros, but I don't see the point in
actually breaking it down.

> 
> This also could allow more simplification, is a check if arena is null
> now needeed?
> 

The check is needed; that is how a thread asks for its own arena (or
share with someone else) when it doesn't have one in its pthread_key.

Siddhesh