Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751221AbdFCUgZ (ORCPT ); Sat, 3 Jun 2017 16:36:25 -0400 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:37107 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751164AbdFCUgX (ORCPT ); Sat, 3 Jun 2017 16:36:23 -0400 Date: Sat, 3 Jun 2017 13:36:20 -0700 From: "Paul E. McKenney" To: Nicolas Pitre Cc: linux-kernel@vger.kernel.org, josh@joshtriplett.org Subject: Re: [PATCH RFC tip/core/rcu] Make SRCU be once again optional Reply-To: paulmck@linux.vnet.ibm.com References: <20170428211546.GA23590@linux.vnet.ibm.com> <20170429001040.GH3956@linux.vnet.ibm.com> <20170512184155.GA9482@linux.vnet.ibm.com> <20170512191005.GE3956@linux.vnet.ibm.com> <20170603035915.GA23375@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 17060320-0048-0000-0000-0000019A2133 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00007166; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000212; SDB=6.00869672; UDB=6.00432357; IPR=6.00649648; BA=6.00005396; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00015695; XFM=3.00000015; UTC=2017-06-03 20:36:22 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 17060320-0049-0000-0000-000041618BDE Message-Id: <20170603203620.GL3721@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2017-06-03_09:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=0 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1703280000 definitions=main-1706030395 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1833 Lines: 42 On Sat, Jun 03, 2017 at 01:18:43AM -0400, Nicolas Pitre wrote: > 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 Ah, thank you for the reminder. I did read that article, but somehow got a few megabytes stuck in my head instead of the correct quarter meg. Anyway, don't look now, but Tiny {S,}RCU just might live on, for a bit longer, anyway. Thanx, Paul