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To: Andre Oppermann <andre@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 03 Jan 2008 01:07:21 +0100."
	<477C2739.5000902@freebsd.org> 
Date: Thu, 03 Jan 2008 00:09:50 +0000
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Cc: Attilio Rao <attilio@freebsd.org>, arch@freebsd.org,
	Robert Watson <rwatson@freebsd.org>, freebsd-arch@freebsd.org
Subject: Re: New "timeout" api, to replace callout 
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In message <477C2739.5000902@freebsd.org>, Andre Oppermann writes:
>Poul-Henning Kamp wrote:
>> In message <477C1CF3.6070301@freebsd.org>, Andre Oppermann writes:
>> 
>>> I fear we have to go for the latter.  Getting a non-sleeping callout
>>> drain seems to be non-trivial.
>> 
>> There is a crucial difference between "non-sleeping" and "not sleeping
>> on my lock" that you should be very careful about in this context.
>> 
>> Which is your requirement ?
>
>Calling timeout_drain() must not sleep and not drop the lock in this
>context (while making any pending timeout go away forever).

Ok, so if the timeouts callback function is running you propose to
do what ?  spin until it returns ?

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.