Re: [PATCH v2 5/5] csky: Cleanup asm/spinlock.h
From: Peter Zijlstra
Date: Thu Jan 07 2021 - 07:46:41 EST
On Sun, Dec 20, 2020 at 03:39:23PM +0000, guoren@xxxxxxxxxx wrote:
> From: Guo Ren <guoren@xxxxxxxxxxxxxxxxx>
>
> There are two implementation of spinlock in arch/csky:
> - simple one (NR_CPU = 1,2)
> - tick's one (NR_CPU = 3,4)
> Remove the simple one.
>
> There is already smp_mb in spinlock, so remove the definition of
> smp_mb__after_spinlock.
Where ? Note that with qspinlock the fast path is
atomic_try_cmpxchg_acquire(), which does not imply anything of the sort.