[PATCH 04/13] powerpc: Use soft_enabled_set api to update paca->soft_enabled

[Madhavan Srinivasan]

On Friday 16 September 2016 03:23 PM, Nicholas Piggin wrote:
> On Thu, 15 Sep 2016 18:31:54 +0530
> Madhavan Srinivasan <maddy at linux.vnet.ibm.com> wrote:
>
>> Force use of soft_enabled_set() wrapper to update paca-soft_enabled
>> wherever possisble. Also add a new wrapper function, soft_enabled_set_return(),
>> added to force the paca->soft_enabled updates.
>>
>> Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
>> ---
>>   arch/powerpc/include/asm/hw_irq.h  | 14 ++++++++++++++
>>   arch/powerpc/include/asm/kvm_ppc.h |  2 +-
>>   arch/powerpc/kernel/irq.c          |  2 +-
>>   arch/powerpc/kernel/setup_64.c     |  4 ++--
>>   arch/powerpc/kernel/time.c         |  6 +++---
>>   5 files changed, 21 insertions(+), 7 deletions(-)
>>
>> diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h
>> index 8fad8c24760b..f828b8f8df02 100644
>> --- a/arch/powerpc/include/asm/hw_irq.h
>> +++ b/arch/powerpc/include/asm/hw_irq.h
>> @@ -53,6 +53,20 @@ static inline notrace void soft_enabled_set(unsigned long enable)
>>   	: : "r" (enable), "i" (offsetof(struct paca_struct, soft_enabled)));
>>   }
>>   
>> +static inline notrace unsigned long soft_enabled_set_return(unsigned long enable)
>> +{
>> +	unsigned long flags;
>> +
>> +	asm volatile(
>> +		"lbz %0,%1(13); stb %2,%1(13)"
>> +		: "=r" (flags)
>> +		: "i" (offsetof(struct paca_struct, soft_enabled)),\
>> +		  "r" (enable)
>> +		: "memory");
>> +
>> +	return flags;
>> +}
> Why do you have the "memory" clobber here while soft_enabled_set() does not?

I did change to function to include a local variable
and update the soft_enabled. But, my bad. It was in the next patch.
I should make the change here. Yes. we dont a "memory" clobber here
which is right. But, this change is not complete and I will correct it.

Maddy

>
> Thanks,
> Nick
>