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Date: Tue, 14 Oct 2003 15:05:47 -0400 (EDT)
From: Jeff Roberson <jroberson@chesapeake.net>
To: John Baldwin <jhb@FreeBSD.org>
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cc: Jeff Roberson <jeff@FreeBSD.org>
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Subject: RE: cvs commit: src/sys/sys mutex.h
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On Tue, 14 Oct 2003, John Baldwin wrote:

>
> On 12-Oct-2003 Jeff Roberson wrote:
> > jeff        2003/10/12 14:02:55 PDT
> >
> >   FreeBSD src repository
> >
> >   Modified files:
> >     sys/sys              mutex.h
> >   Log:
> >    - Implement a mtx_ownedby() macro which can be used to determine if a
> >      particular thread owns a mutex.  This cannot be done without races
> >      unless the thread is curthread.
>
> This is a very bad idea.  What use do you have for this that is not
> already handled by mtx_owned() or a mutex assertion?

I know it is racy in most contexts.  I use it to check to see if a thread
on the runq owns giant.  Since I have the sched lock it isn't racy but
even if it was it wouldn't matter in this case.

Cheers,
Jeff

>
> --
>
> John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
> "Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/
>