From mboxrd@z Thu Jan 1 00:00:00 1970 From: zhanzhenbo@gmail.com (Steve zhan) Date: Sat, 19 Jan 2013 14:33:58 +0800 Subject: ARM: ux500:mach-ux500/cpuidle.c spinlock dis-matching Message-ID: <20130119063358.GA27760@android11.spreadtrum.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Daniel,Linus Walleij. Using MUTT resubmit this for http://lists.infradead.org/pipermail/linux-arm-kernel/2013-January/139893.html --- Steve commit 99d0a05d163bd070eba7caab7e772206edbcbbc9 Author: steve zhan Date: Mon Jan 7 18:19:14 2013 +0800 ARM: ux500: add spin_unlock(&master_lock). Add the missing spin_unlock statement to unlock master_lock when prcmu_gic_decouple() return TRUE Signed-off-by: steve zhan diff --git a/arch/arm/mach-ux500/cpuidle.c b/arch/arm/mach-ux500/cpuidle.c index b54884bd..ce91493 100644 --- a/arch/arm/mach-ux500/cpuidle.c +++ b/arch/arm/mach-ux500/cpuidle.c @@ -40,8 +40,10 @@ static inline int ux500_enter_idle(struct cpuidle_device *dev, goto wfi; /* decouple the gic from the A9 cores */ - if (prcmu_gic_decouple()) + if (prcmu_gic_decouple()) { + spin_unlock(&master_lock); goto out; + } /* If an error occur, we will have to recouple the gic * manually */ 2013/1/7 Daniel Lezcano : > On 01/07/2013 06:50 AM, steve.zhan wrote: >> Hi Daniel, >> >> Happy new year, Thank you for reply. >> Sorry for that i have refer the old patch email. >> I have updated the patch, Pls check the URL: >> http://lists.infradead.org/pipermail/linux-arm-kernel/2012-December/138939.html >> Now i am using gmail GUI tools to send mail, i will switch email tool >> to MUTT to commit the other patchs in the future. > > Ok. > > Please do not introduce a new variable which is at the end pointless and > add more complexity. > > You can simply remove the if statement for prcmu_gic_decouple(), or > unlock if it fails. > > Thanks > -- Daniel > >> -------------- >> steve.zhan >> >> 2013/1/7, Daniel Lezcano : >>> On 12/28/2012 08:06 AM, steve.zhan wrote: >>>> Hi Daniel, >>> >>> Hi Steve, >>> >>> sorry I missed your email. >>> >>>> >>>> I think we must unlock the master spinlock even >>>> prcmu_gic_decouple function now always return 0. >>>> Could you give some infos about this? >>> >>> I agree, that would be cleaner. >>> >>> AFAICS, your patch does not solve the problem because 'recouple' will be >>> false if prcmu_gic_decouple fails, so the lock will never be release. >>> >>> That will be simpler to do: >>> >>> if (prcmu_gic_decouple()) { >>> spin_unlock(&master); >>> goto out; >>> } >>> >>> no ? >>> >>>> Thanks. >>>> >>>> diff --git a/arch/arm/mach-ux500/cpuidle.c >>>> b/arch/arm/mach-ux500/cpuidle.c >>>> index b54884bd..b0759ce 100644 >>>> --- a/arch/arm/mach-ux500/cpuidle.c >>>> +++ b/arch/arm/mach-ux500/cpuidle.c >>>> @@ -29,6 +29,7 @@ static inline int ux500_enter_idle(struct cpuidle_device >>>> *dev, >>>> { >>>> int this_cpu = smp_processor_id(); >>>> bool recouple = false; >>>> + bool locked = false; >>>> >>>> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &this_cpu); >>>> >>>> @@ -39,6 +40,8 @@ static inline int ux500_enter_idle(struct cpuidle_device >>>> *dev, >>>> if (!spin_trylock(&master_lock)) >>>> goto wfi; >>>> >>>> + locked = true; >>>> + >>>> /* decouple the gic from the A9 cores */ >>>> if (prcmu_gic_decouple()) >>>> goto out; >>>> @@ -76,7 +79,7 @@ static inline int ux500_enter_idle(struct cpuidle_device >>>> *dev, >>>> /* When we switch to retention, the prcmu is in charge >>>> * of recoupling the gic automatically */ >>>> recouple = false; >>>> - >>>> + locked = false; >>>> spin_unlock(&master_lock); >>>> } >>>> wfi: >>>> @@ -86,7 +89,8 @@ out: >>>> >>>> if (recouple) { >>>> prcmu_gic_recouple(); >>>> - spin_unlock(&master_lock); >>>> + if (locked) >>>> + spin_unlock(&master_lock); >>>> } >>>> >>>> clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &this_cpu); >>>> >>>> >>>> >>>> Steve Zhan >>>> >>> >>> >>> -- >>> Linaro.org ?? Open source software for ARM SoCs >>> >>> Follow Linaro: Facebook | >>> Twitter | >>> Blog >>> >>> >> >> > > > -- > Linaro.org ?? Open source software for ARM SoCs > > Follow Linaro: Facebook | > Twitter | > Blog >