Re: [PATCH for-4.17 2/2] powerpc: Remove smp_mb() from arch_spin_is_locked()
From: Michael Ellerman
Date: Wed Apr 04 2018 - 06:28:47 EST
Peter Zijlstra <peterz@xxxxxxxxxxxxx> writes:
> On Wed, Mar 28, 2018 at 01:04:36PM +0200, Peter Zijlstra wrote:
>> On Wed, Mar 28, 2018 at 04:25:37PM +1100, Michael Ellerman wrote:
>> > Documenting it would definitely be good, but even then I'd be inclined
>> > to leave the barrier in our implementation. Matching the documented
>> > behaviour is one thing, but the actual real-world behaviour on well
>> > tested platforms (ie. x86) is more important.
>>
>> By that argument you should switch your spinlock implementation to RCpc
>> and include that SYNC in either lock or unlock already ;-)
>
> *RCsc* obviously... clearly I need to wake up moar.
It's just a jumble of letters to me - I didn't even notice ;)
cheers