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To: John Baldwin <jhb@FreeBSD.org>
In-Reply-To: Your message of "Thu, 23 Oct 2003 14:30:15 EDT."
             <XFMail.20031023143015.jhb@FreeBSD.org> 
Date: Thu, 23 Oct 2003 13:05:57 -0700
From: Kirk McKusick <mckusick@beastie.mckusick.com>
cc: arch@FreeBSD.org
Subject: Re: Convert P_COWINPROGRESS to per-thread lock-less flag.. 
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	Date: Thu, 23 Oct 2003 14:30:15 -0400 (EDT)
	From: John Baldwin <jhb@FreeBSD.org>
	To: arch@FreeBSD.org
	Subject: Convert P_COWINPROGRESS to per-thread lock-less flag..
	Cc: mckusick@mckusick.com
	X-ASK-Info: Whitelist match

	As part of the proc locking, I have a patch that converts the
	per-process P_COWINPROGRESS flag to a per-thread flag instead.
	The per-thread flag is a TDP_COWINPROGRESS flag stored in
	td_pflags which does not require any locks.  This removes the
	last user of p_flag that does not use the proc lock.  Are there
	any problems with making this flag per-thread instead of
	per-process?

	http://www.FreeBSD.org/~jhb/patches/cow.patch

	-- 

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

I do not see any problems with it being per-thread.

	Kirk McKusick