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Date: Tue, 1 Apr 2008 09:56:24 +0200
From: Roman Divacky <rdivacky@freebsd.org>
To: "Rao, Nikhil" <nikhil.rao@intel.com>
Message-ID: <20080401075623.GA19770@freebsd.org>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: pfind() and the proc structure
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On Mon, Mar 31, 2008 at 11:03:31PM -0700, Rao, Nikhil wrote:
> Hi List,
> 
> The pfind(..) (in kern_proc.c) function below returns the proc structure
> for the PID passed in
> 
> Say the thread that calls pfind() gets blocked at PROC_LOCK(p) (line 255
> below), in the meantime what prevents the process from exiting and
> deallocating the proc structure ? Maybe I am missing something simple or
> the answer requires knowledge of the mutex implementation.

thats what the allproc_lock is there for