Subject: Re: PR 32535
To: None <tech-kern@NetBSD.org>
From: Pavel Cahyna <pavel@NetBSD.org>
Date: 10/24/2006 22:25:57
On Tue, Oct 24, 2006 at 11:13:49AM -0700, Bill Studenmund wrote:
> I wish we had gdb. I have a script that is supposed to walk a vnode chain.
> So you could point it at that vnode, it would find the process owning it,
> and see what it's sleeping on. And so on until we find a vnode owned by a
> process not sleeping on a vnode. _That_ is the source of the problem.
> The other option I see is we can extend ddb's print routines so that it
> will print the process that holds the lock on a vnode. Then you can dump a
> vnode, see a proc, look at that proc's wait channel, and itterate.
lockmgr_printinfo should do it. BTW I have a patch to detect lock cycles,
which should help debugging vnode deadlocks. Any interest?