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Date: Sat, 3 Jun 2017 01:18:43 -0400 (EDT)
From: Nicolas Pitre <nicolas.pitre@linaro.org>
To: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
cc: linux-kernel@vger.kernel.org, josh@joshtriplett.org
Subject: Re: [PATCH RFC tip/core/rcu] Make SRCU be once again optional
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On Fri, 2 Jun 2017, Paul E. McKenney wrote:

> On Fri, May 12, 2017 at 12:10:05PM -0700, Paul E. McKenney wrote:
> > On Fri, May 12, 2017 at 02:59:48PM -0400, Nicolas Pitre wrote:
> > > On Fri, 12 May 2017, Paul E. McKenney wrote:
> 
> [ . . . ]
> 
> > > No.  "Available in mainline" is the name of the game for all I do. If it 
> > > can't be made acceptable for mainline then it basically has no chance of 
> > > gaining traction and becoming generally useful. My approach is therefore 
> > > to always find solutions that can be maintained upstream and contributed 
> > > to with minimal fuss by anyone.
> > 
> > OK, then wish me luck.  ;-)
> 
> And still quite a bit of back and forth.  How are things with tty?
> 
> One question that came up -- what sort of SoCs are you targeting?
> A number of people are insisting that smartphone SoCs with 256M DRAM
> are the minimal systems of the future.  This seems unlikely to me,
> given the potential for extremely cheap SoCs with EDRAM or some such,
> but figured I should ask what you are targeting.

I'm targetting 256 *kilobytes* of RAM. Most likely SRAM. That's not for 
smart phones but really cheap IoT devices. That's the next area for 
(trimmed down) Linux to conquer. Example targets are STM32 chips.

Please see the following for the rationale and how to get there:

https://lwn.net/Articles/721074/

http://www.mail-archive.com/search?l=mid&q=alpine.LFD.2.20.1703241215540.2304%40knanqh.ubzr


Nicolas