From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH -v9][RFC] mutex: implement adaptive spinning
Date: Tue, 13 Jan 2009 19:12:22 +0100
Message-ID: <20090113181222.GA24910@elte.hu>
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Cc: Peter Zijlstra <peterz@infradead.org>,
	"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>,
	Gregory Haskins <ghaskins@novell.com>,
	Matthew Wilcox <matthew@wil.cx>,
	Andi Kleen <andi@firstfloor.org>,
	Chris Mason <chris.mason@oracle.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	linux-btrfs <linux-btrfs@vger.kernel.org>,
	Thomas Gleixner <tglx@linutronix.de>,
	Nick Piggin <npiggin@suse.de>,
	Peter Morreale <pmorreale@novell.com>,
	Sven Dietrich <SDietrich@novell.com>,
	Dmitry Adamushko <dmitry.adamushko@gmail.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Return-path: <linux-fsdevel-owner@vger.kernel.org>
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* Linus Torvalds <torvalds@linux-foundation.org> wrote:

> 
> 
> On Tue, 13 Jan 2009, Peter Zijlstra wrote:
> > 
> > Ok, tested only 1, but that was the one I remember lockups from -- and
> > that seems to be good with the cmpxchg.
> > 
> > Do you fancy me sending v10 or will you make that change locally?
> 
> I'd like to get this in, but I'm not going to apply it in any case 
> without way more testing.
> 
> It missed the merge window, but I'm potentially willing to let it slip 
> in - but only if there are a fair number of people willing to do numbers 
> and some harsh testing. Preferably people who did see problems earlier, 
> ie at a minimum Chris and Ingo under the loads they used before and saw 
> issues with.

I am tracking Peter's code in tip/core/locking:

 c10b491: mutex: implement adaptive spinning, v8
 c356a7c: mutex: implement adaptive spinning, v7
 b89e5d8: mutex: implement adaptive spinning, v6
 237ac94: mutex: implement adaptive spinning

And v8 is rock solid in all my testing - and i'll give v10 a similar 
workout as well.

Would you prefer a single commit or is this kind of delta development 
history useful, with all the variants (at least the later, more promising 
ones) included?

The commits are in a tight group with no merges inbetween.

	Ingo