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Date: Tue, 9 Jun 2015 11:16:10 +0100
From: Ruslan Bukin <br@freebsd.org>
To: John Baldwin <jhb@freebsd.org>
Cc: src-committers@freebsd.org, svn-src-all@freebsd.org,
 svn-src-head@freebsd.org
Subject: Re: svn commit: r284153 - head/sys/kern
Message-ID: <20150609101610.GA47083@bsdpad.com>
References: <201506081406.t58E6mvA033492@svn.freebsd.org>
 <20150608144629.GA37834@bsdpad.com>
 <1554833.IUNnl2bGYK@ralph.baldwin.cx>
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On Mon, Jun 08, 2015 at 02:04:45PM -0400, John Baldwin wrote:
> On Monday, June 08, 2015 03:46:29 PM Ruslan Bukin wrote:
> > For some reason it hangs for me after 'random' lines on arm64
> 
> Are you using dtrace?  It looks like sdt was using the public symbol before
> but in a context where the caller held the lock.  I will revert this for now.
> I think I can perhaps make it 'automatic' by having it acquire a read lock
> (possibly recursing) if it doesn't already hold a write lock.
> 

Yes, I'm using DTrace. And you right: if I remove dtrace_sdt from kernel,
then the same revision works fine for me.

Ruslan