From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH -v7][RFC]: mutex: implement adaptive spinning
Date: Mon, 12 Jan 2009 09:40:41 +0100
Message-ID: <20090112084041.GA21976@elte.hu>
References: <alpine.LFD.2.00.0901091347170.6528@localhost.localdomain> <20090109231227.GA25070@elte.hu> <alpine.LFD.2.00.0901091522250.6528@localhost.localdomain> <20090110010125.GA31031@elte.hu> <1231549697.5700.7.camel@brick> <alpine.LFD.2.00.0901091713150.6528@localhost.localdomain> <49682C05.7030407@zytor.com> <alpine.LFD.2.00.0901092119100.6528@localhost.localdomain> <20090111005458.GA5363@elte.hu> <20090112015620.GA6428@shareable.org>
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Harvey Harrison <harvey.harrison@gmail.com>,
	Andi Kleen <andi@firstfloor.org>,
	Chris Mason <chris.mason@oracle.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Steven Rostedt <rostedt@goodmis.org>,
	paulmck@linux.vnet.ibm.com, Gregory Haskins <ghaskins@novell.com>,
	Matthew Wilcox <matthew@wil.cx>,
	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>,
	Heiko Carstens <heiko.carstens@de.ibm.com>
To: Jamie Lokier <jamie@shareable.org>
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* Jamie Lokier <jamie@shareable.org> wrote:

> Ingo Molnar wrote:
> > If it's used once in a single .c file it should be inlined even if
> > it's large.
> 
> As Linus has pointed out, because of GCC not sharing stack among 
> different inlined functions, the above is surprisingly not true.

Yes, but note that this has no relevance to the specific case of 
CONFIG_OPTIMIZE_INLINING: GCC can at most decide to inline _less_, not 
more. I.e. under CONFIG_OPTIMIZE_INLINING we can only end up having less 
stack sharing trouble.

	Ingo