Re: [libvirt] [PATCH V11 2/7] Support for atomic operations on integers

[Stefan Berger <stefanb linux vnet ibm com>]

On 04/19/2012 02:08 PM, Eric Blake wrote:
> On 04/17/2012 08:44 AM, Stefan Berger wrote:
> > For threading support, add atomic add and sub operations working on
> > integers. Base this on locking support provided by virMutex.
>
> virMutex is very heavyweight.  I'd love it if we could use gcc
> primitives and/or MSVC libc primitives (where they are known to be
> available), for a lighter-weight implementation on platforms that
> support it.  See this patch proposal (now a year old!) for some ideas
> that we should fold in before 0.9.12:
>
> https://www.redhat.com/archives/libvir-list/2011-April/msg00368.html
Well, I wasn't aware of this previous proposal and had actually looked 
in pthread for some form of atomic support.
I already pushed this patch now. We can add some compiler- and 
architecture-specific #ifdef's around the few existing functions. So the 
existing implementation probably has a place but can be improved upon.

    Stefan