2017-06-02 18:36:29

by Vineet Gupta

Subject: Re: [PATCH v2 08/11] ARC: [plat-eznps] spinlock aware for MTM

On 05/27/2017 11:52 PM, Noam Camus wrote:
> From: Noam Camus <[email protected]>
>
> This way when we execute "ex" during trying to hold lock we can switch to
> other HW thread and utilize the core intead of just spinning on a lock.
>
> We noticed about 10% improvement of execution time with hackbench test.
>
> Signed-off-by: Noam Camus <[email protected]>
> ---
> arch/arc/include/asm/spinlock.h | 6 ++++++
> 1 files changed, 6 insertions(+), 0 deletions(-)
>
> diff --git a/arch/arc/include/asm/spinlock.h b/arch/arc/include/asm/spinlock.h
> index 233d5ff..0a54ce7 100644
> --- a/arch/arc/include/asm/spinlock.h
> +++ b/arch/arc/include/asm/spinlock.h
> @@ -252,9 +252,15 @@ static inline void arch_spin_lock(arch_spinlock_t *lock)
>
> __asm__ __volatile__(
> "1: ex %0, [%1] \n"
> +#ifdef CONFIG_EZNPS_MTM_EXT
> + " .word %3 \n"
> +#endif
> " breq %0, %2, 1b \n"
> : "+&r" (val)
> : "r"(&(lock->slock)), "ir"(__ARCH_SPIN_LOCK_LOCKED__)
> +#ifdef CONFIG_EZNPS_MTM_EXT
> + , "i"(CTOP_INST_SCHD_RW)
> +#endif
> : "memory");
>
> /*
>

This is ugly - I will fix it up here to create an NPS version of arch_spin_lock !

-Vineet

2017-06-04 06:11:45

by Noam Camus

Subject: RE: [PATCH v2 08/11] ARC: [plat-eznps] spinlock aware for MTM

> From: Vineet Gupta [mailto:[email protected]]
> Sent: Friday, June 2, 2017 21:36 PM
...

>> arch/arc/include/asm/spinlock.h | 6 ++++++
>> 1 files changed, 6 insertions(+), 0 deletions(-)
>>
>> diff --git a/arch/arc/include/asm/spinlock.h
>> b/arch/arc/include/asm/spinlock.h index 233d5ff..0a54ce7 100644
>> --- a/arch/arc/include/asm/spinlock.h
>> +++ b/arch/arc/include/asm/spinlock.h
>> @@ -252,9 +252,15 @@ static inline void arch_spin_lock(arch_spinlock_t
>> *lock)
>>
>> __asm__ __volatile__(
>> "1: ex %0, [%1] \n"
>> +#ifdef CONFIG_EZNPS_MTM_EXT
>> + " .word %3 \n"
>> +#endif
>> " breq %0, %2, 1b \n"
>> : "+&r" (val)
>> : "r"(&(lock->slock)), "ir"(__ARCH_SPIN_LOCK_LOCKED__)
>> +#ifdef CONFIG_EZNPS_MTM_EXT
>> + , "i"(CTOP_INST_SCHD_RW)
>> +#endif
>> : "memory");
>>
>> /*
>>

>This is ugly - I will fix it up here to create an NPS version of arch_spin_lock !
TNX

-Noam