On Tue, 16 Mar 2021, Nicholas Piggin wrote:
One request, could you add a comment in place that references
smp_cond_load_relaxed() so this commit can be found again if
someone looks at it? Something like this
/*
* smp_cond_load_relaxed was found to have performance problems if
* implemented
Excerpts from Davidlohr Bueso's message of March 9, 2021 11:59 am:
> 49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
> busy-waiting pausing with a preferred SMT priority pattern, lowering
> the priority (reducing decode cycles) during the whole loop slowpath.
>
> However, data
On Tue, Mar 09, 2021 at 07:46:11AM -0800, Davidlohr Bueso wrote:
> On Tue, 09 Mar 2021, Michal Such�nek wrote:
>
> > On Mon, Mar 08, 2021 at 05:59:50PM -0800, Davidlohr Bueso wrote:
> > > 49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
> > > busy-waiting pausing with a preferred
On Tue, 09 Mar 2021, Michal Such�nek wrote:
On Mon, Mar 08, 2021 at 05:59:50PM -0800, Davidlohr Bueso wrote:
49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
busy-waiting pausing with a preferred SMT priority pattern, lowering
the priority (reducing decode cycles) during the
On Mon, Mar 08, 2021 at 05:59:50PM -0800, Davidlohr Bueso wrote:
> 49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
> busy-waiting pausing with a preferred SMT priority pattern, lowering
> the priority (reducing decode cycles) during the whole loop slowpath.
>
> However, data shows
49a7d46a06c3 (powerpc: Implement smp_cond_load_relaxed()) added
busy-waiting pausing with a preferred SMT priority pattern, lowering
the priority (reducing decode cycles) during the whole loop slowpath.
However, data shows that while this pattern works well with simple
spinlocks, queued spinlocks
