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Date:   Thu, 3 Aug 2023 10:50:04 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Guo Ren <guoren@kernel.org>
Cc:     Alex Kogan <alex.kogan@oracle.com>, linux@armlinux.org.uk,
        mingo@redhat.com, will.deacon@arm.com, arnd@arndb.de,
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        tglx@linutronix.de, bp@alien8.de, hpa@zytor.com, x86@kernel.org,
        guohanjun@huawei.com, jglauber@marvell.com,
        steven.sistare@oracle.com, daniel.m.jordan@oracle.com,
        dave.dice@oracle.com
Subject: Re: [PATCH v15 3/6] locking/qspinlock: Introduce CNA into the slow
 path of qspinlock
Message-ID: <20230803085004.GF212435@hirez.programming.kicks-ass.net>
References: <20210514200743.3026725-1-alex.kogan@oracle.com>
 <20210514200743.3026725-4-alex.kogan@oracle.com>
 <ZMrjPWdWhEhwpZDo@gmail.com>
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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@kernel.org/
> 
> 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?