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Subject: Re: [OMPI devel] ob1 and req->req_state
From: Brian W. Barrett (brbarret_at_[hidden])
Date: 2008-06-23 15:23:17

On Mon, 23 Jun 2008, Jeff Squyres wrote:

> On Jun 23, 2008, at 3:17 PM, Brian W. Barrett wrote:
>> Just because it's volatile doesn't mean that adds are atomic. There's at
>> least one place in the PML (or used to be) where two threads could
>> decrement that counter at the same time.
> With atomics, then both subtracts should occur, right? So a request could go
> from ACTIVE -> INACTIVE -> INVALID. Is that what is desired? (I honestly
> don't know enough about ob1 to say)
> Or should we just be assigning a specific state, rather than relying on
> subtracting? That was my real question.

I honestly don't know. I just remember that there were some cases where
we were doing crazy counting.