From mboxrd@z Thu Jan 1 00:00:00 1970 From: alex.shi@linaro.org (Alex Shi) Date: Tue, 19 Nov 2013 11:15:12 +0800 Subject: =?GB2312?B?tPC4tDogYSBidWcgb24gTk9fSFpfRlVMTF9BTEw=?= In-Reply-To: <548C3FF8E9B1F945A9FEE3533A16C6CD4E9C319D@szxema507-mbs.china.huawei.com> References: <52843855.5060509@linaro.org> <52847FBE.9070501@linaro.org> <52848547.9080604@linaro.org> <528AD4E4.9010103@linaro.org> <548C3FF8E9B1F945A9FEE3533A16C6CD4E9C319D@szxema507-mbs.china.huawei.com> Message-ID: <528AD7C0.40702@linaro.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 11/19/2013 11:10 AM, Sunshaojie wrote: > Hi Alex > > I tested it on kernel V3.10 and on 32bits ARM system. > Where did you see this option opened only for 64bits? > kernel/time/Kconfig: config NO_HZ_FULL bool "Full dynticks system (tickless)" # NO_HZ_COMMON dependency depends on !ARCH_USES_GETTIMEOFFSET && GENERIC_CLOCKEVENTS # We need at least one periodic CPU for timekeeping depends on SMP # RCU_USER_QS dependency depends on HAVE_CONTEXT_TRACKING # VIRT_CPU_ACCOUNTING_GEN dependency depends on 64BIT <======= select NO_HZ_COMMON select RCU_USER_QS select RCU_NOCB_CPU select VIRT_CPU_ACCOUNTING_GEN select IRQ_WORK > > -----????----- > ???: Alex Shi [mailto:alex.shi at linaro.org] > ????: 2013?11?19? 11:03 > ???: Shaojie Sun; viresh kumar > ??: Vincent Guittot; Fathi Boudra; Guodong Xu; Amit Kucheria; Chris Redpath; Linaro Kernel; LAK; Fr?d?ric Weisbecker; Kevin Hilman; Sunshaojie > ??: Re: a bug on NO_HZ_FULL_ALL > > On 11/14/2013 05:54 PM, Shaojie Sun wrote: >> No, I think it is a bug. >> >> Because I tested the option with NO_HZ_FULL and without >> NO_HZ_FULL_ALL. It had only little interruptes on CPU0 twd. >> With same code, I added NO_HZ_FULL_ALL option. It had too many >> interruptes on CPU0 twd. >> >> So the sumbitter just didn't test twd interrupts, when he expanded >> NO_HZ_FULL option to all cpu. >> >> On Thu, Nov 14, 2013 at 4:09 PM, viresh kumar wrote: >>> On Thursday 14 November 2013 01:35 PM, Vincent Guittot wrote: >>>> AFAICT, It's a none issue. In full nohz, a timer fires periodically >>>> (around 4sec period on ARM IIRC) on one cpu (cpu0). >>> >>> Timer should always be running on CPU0, its out of nohz-full domain. >>> Its cpu 1, where it will fire after long delays.. >>> >>> >>> https://wiki.linaro.org/WorkingGroups/PowerManagement/Doc/AdaptiveTic >>> kless > > > Shaojie, > which kernel version has this bug? > I just find only the v3.13 kernel has opened the NO_HZ_FULL for 32 bit kernel. and my testing base it. > > but for lsk, it is 3.10 kernel, so unless you are using 64bit kernel to do testing, is it right? > > -- > Thanks > Alex > -- Thanks Alex