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Date: Tue, 30 Oct 2007 10:45:36 +0800
From: David Xu <davidxu@FreeBSD.org>
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To: Daniel Eischen <deischen@FreeBSD.org>
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Cc: cvs-src@FreeBSD.org, Kris Kennaway <kris@FreeBSD.org>,
	src-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject: Re: cvs commit: src/lib/libthr/thread thr_mutex.c
 src/lib/libkse/thread thr_mutex.c src/include pthread.h
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Daniel Eischen wrote:
> On Tue, 30 Oct 2007, David Xu wrote:
> 
>> I am not sure PTHREAD_MUTEX_ADAPTIVE_NP is a correct solution, in fact
>> I think this is Linux crap, shouldn't PTHREAD_PRIO_PROTECT and
>> PTHREAD_PRIO_INHERIT mutex be adaptivly spinned ?
>> also this commit does not change mutex_self_lock() to handle the
>> PTHREAD_MUTEX_ADAPTIVE_NP, what is the PTHREAD_MUTEX_ADAPTIVE_NP
>> definition when the mutex is already locked by the currect thread ?
>> deadlock or return error code ?
> 
> 
> I tend to agree with the "Linux crap" comment, but I hesitate
> to use those words considering the recent sensor framework
> incident ;-)
> 

Isn't this commit an incident too ? :-) if it is not, then
we should retire from FreeBSD now, as two thread library
maintainers were bypassed.

> As I said in previous email, I would rather see our default
> mutex implementations improved instead of adding new interfaces.
> If it's really necessary in the short term, perhaps an
> environment variable that can be set to force all mutexes
> to be adaptive (and when kern.smp.cpus > 1 perhaps?).
> 
Yes, an environment variable is good idea.

Regards,
David Xu