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Subject: Re: [hwloc-devel] thread safety
From: Jeff Squyres (jsquyres_at_[hidden])
Date: 2010-03-12 11:38:48

On Mar 12, 2010, at 8:31 AM, Samuel Thibault wrote:

> No, because that will not automatically issue hardware memory barriers,
> which are needed on basically all architectures but x86 (which has
> in-order stores) to ensure seeing writes coherently.

Ok, fine.

I'm not understanding how this conversation corresponds to one of your prior statements on this thread that you thought hwloc was already thread safe.

The discussion we've had sounds like it's somewhat equivalent to MPI_THREAD_SERIALIZED -- you can do whatever you want as long as you ensure a) there's only writer 1 thread to a given object at a time, and b) the app is responsible for all synchronization and memory consistency.

Am I missing something?

Jeff Squyres
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