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Date:   Sat, 25 Jan 2020 12:19:31 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     Alex Kogan <alex.kogan@oracle.com>
Cc:     Waiman Long <longman@redhat.com>, linux@armlinux.org.uk,
        Ingo Molnar <mingo@redhat.com>,
        Will Deacon <will.deacon@arm.com>,
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        linux-kernel@vger.kernel.org, Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>, hpa@zytor.com, x86@kernel.org,
        Hanjun Guo <guohanjun@huawei.com>,
        Jan Glauber <jglauber@marvell.com>,
        Steven Sistare <steven.sistare@oracle.com>,
        Daniel Jordan <daniel.m.jordan@oracle.com>,
        dave.dice@oracle.com
Subject: Re: [PATCH v8 4/5] locking/qspinlock: Introduce starvation avoidance
 into CNA
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On Fri, Jan 24, 2020 at 01:19:05PM -0500, Alex Kogan wrote:

> Is there a lightweight way to identify such a “prioritized” thread?

No; people might for instance care about tail latencies between their
identically spec'ed worker tasks.

In general it turns out that priority is a dynamic concept, not a static
one.