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From: John Baldwin <jhb@FreeBSD.org>
To: David Schultz <das@FreeBSD.org>
Date: Mon, 4 Oct 2004 10:34:31 -0400
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Subject: Re: cvs commit: src/sys/kern kern_fork.c
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On Friday 01 October 2004 01:01 am, David Schultz wrote:
> das         2004-10-01 05:01:29 UTC
>
>   FreeBSD src repository
>
>   Modified files:
>     sys/kern             kern_fork.c
>   Log:
>   Avoid calling _PHOLD(p1) with p2's lock held, since _PHOLD()
>   may block to swap in p1.  Instead, call _PHOLD earlier, at a
>   point where the only lock held happens to be p1's.

FWIW, I don't think this can actually happen because curthread belonging to p1 
is executing and it wouldn't be executing unless it was swapped in, so I 
don't think that PHOLD could ever have blocked.

-- 
John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve"  =  http://www.FreeBSD.org