From owner-freebsd-arch@FreeBSD.ORG  Sun Aug 10 07:14:33 2008
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To: John Baldwin <jhb@freebsd.org>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 09 Aug 2008 16:37:33 -0400."
	<200808091637.33820.jhb@freebsd.org> 
Date: Sun, 10 Aug 2008 07:14:31 +0000
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Sender: phk@critter.freebsd.dk
Cc: arch@freebsd.org
Subject: Re: Make MOD_QUIESCE a bit more useful.. 
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In message <200808091637.33820.jhb@freebsd.org>, John Baldwin writes:
>So currently the MOD_QUIESCE event is posted to a module when unloading a kld 
>so it can veto non-forced unloads.  However, the current implementation in 
>the kernel linker is to run through all the modules in a file, posting 
>MOD_QUIESCE followed by MOD_UNLOAD on each module serially.  Thus, if you 
>have multiple modules in a single kld and one of the modules veto's an unload 
>request via MOD_QUIESCE, you don't know as the module author if any of your 
>modules were unloaded via MOD_UNLOAD or not.  I think a better approach would 
>be to change the kernel linker to invoke MOD_QUIESCE on all modules in a 
>single pass first.  If none of those fail (or it's a forced unload), then it 
can do a second pass invoking MOD_UNLOAD on all the modules.

I thought it already worked that way, so no objection.


-- 
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.