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Date:   Thu, 16 Mar 2023 00:56:20 +0100 (CET)
From:   Christoph Lameter <cl@gentwo.de>
To:     Marcelo Tosatti <mtosatti@redhat.com>
cc:     Aaron Tomlin <atomlin@atomlin.com>,
        Frederic Weisbecker <frederic@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v2 02/11] this_cpu_cmpxchg: ARM64: switch this_cpu_cmpxchg
 to locked, add _local function
In-Reply-To: <20230209153204.683821550@redhat.com>
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References: <20230209150150.380060673@redhat.com> <20230209153204.683821550@redhat.com>
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On Thu, 9 Feb 2023, Marcelo Tosatti wrote:

> Goal is to have vmstat_shepherd to transfer from
> per-CPU counters to global counters remotely. For this,
> an atomic this_cpu_cmpxchg is necessary.

The definition for this_cpu_functionality is that it is *not* incurring
atomic overhead and it was introduced to *avoid* the overhead of atomic
operations.

This sabotages this_cpu functionality,