Subject: Re: Final reaper removal patch
To: YAMAMOTO Takashi <yamt@mwd.biglobe.ne.jp>
From: Jaromir Dolecek <jdolecek@NetBSD.org>
List: tech-kern
Date: 01/09/2004 10:33:51
YAMAMOTO Takashi wrote:
> lwp_exit2() should acquire kernel lock.  otherwise it deadlocks.

I'm not sure. AFAICS it uses correct lock protocol.

Normal lock order is:
1. KERNEL_PROC_LOCK
2. other spinlocks

The lwp_exit2() doesn't take KERNEL_PROC_LOCK(), only takes
the other spinlocks. Thus, it shouldn't deadlock.
Deadlock would be possible only if there would be any code
path where lwp_exit2() acquires some others locks before
taking KERNEL_PROC_LOCK. Right?

Jaromir
-- 
Jaromir Dolecek <jdolecek@NetBSD.org>            http://www.NetBSD.cz/
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