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Date: Fri, 9 May 2014 10:21:33 -0700
From: josh@joshtriplett.org
To: Christoph Lameter <cl@linux.com>
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Cc: Sarah Sharp <sarah@minilop.net>, ksummit-discuss@lists.linuxfoundation.org,
	Greg KH <gregkh@linuxfoundation.org>,
	James Bottomley <James.Bottomley@HansenPartnership.com>,
	Julia Lawall <julia.lawall@lip6.fr>, Darren Hart <darren@dvhart.com>,
	Dan Carpenter <dan.carpenter@oracle.com>
Subject: Re: [Ksummit-discuss] [CORE TOPIC] Kernel tinification: shrinking
 the kernel and avoiding size regressions
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On Fri, May 09, 2014 at 11:55:23AM -0500, Christoph Lameter wrote:
> On Fri, 9 May 2014, Steven Rostedt wrote:
> > Size may not be as important as having reuse of code. Perhaps if you
> > can tweak several functions to call one helper function, which may
> > actually increase the total size of the kernel, but having more helper
> > functions that live in cache longer may be of benefit.
> 
> More helper functions means more use of l1 cache lines which reduces
> performance.

If done poorly, but on the other hand, factoring a common code path out
of many call sites into one helper function makes it more likely that
helper function will remain cached.

- Josh Triplett