Re: [PATCH v15 3/6] locking/qspinlock: Introduce CNA into the slow path of qspinlock

From: Peter Zijlstra
Date: Thu Aug 03 2023 - 04:50:51 EST


On Wed, Aug 02, 2023 at 07:14:05PM -0400, Guo Ren wrote:

> The pv_ops is belongs to x86 custom frame work, and it prevent other
> architectures connect to the CNA spinlock.

static_call() exists as a arch neutral variant of this.

> I'm working on riscv qspinlock on sg2042 64 cores 2/4 NUMA nodes
> platforms. Here are the patches about riscv CNA qspinlock:
> https://lore.kernel.org/linux-riscv/20230802164701.192791-19-guoren@xxxxxxxxxx/
>
> What's the next plan for this patch series? I think the two-queue design
> has satisfied most platforms with two NUMA nodes.

What has been your reason for working on CNA? What lock has been so
contended you need this?