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Date: Wed, 25 Oct 2023 08:37:00 -0700
From: Stephen Hemminger <stephen@networkplumber.org>
To: Thomas Monjalon <thomas@monjalon.net>
Cc: dev@dpdk.org, David Marchand <david.marchand@redhat.com>,
 stable@dpdk.org, Morten =?UTF-8?B?QnLDuHJ1cA==?=
 <mb@smartsharesystems.com>, Anatoly Burakov <anatoly.burakov@intel.com>,
 Dmitry Kozlyuk <dmitry.kozliuk@gmail.com>, Narcisa Ana Maria Vasile
 <navasile@linux.microsoft.com>, Dmitry Malloy <dmitrym@microsoft.com>,
 Pallavi Kadam <pallavi.kadam@intel.com>, Tyler Retzlaff
 <roretzla@linux.microsoft.com>, Andrew Rybchenko
 <andrew.rybchenko@oktetlabs.ru>, Konstantin Ananyev
 <konstantin.v.ananyev@yandex.ru>
Subject: Re: [PATCH v2] eal/unix: allow creating thread with real-time priority
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In-Reply-To: <20231025151352.995318-1-thomas@monjalon.net>
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On Wed, 25 Oct 2023 17:13:14 +0200
Thomas Monjalon <thomas@monjalon.net> wrote:

>  	case RTE_THREAD_PRIORITY_REALTIME_CRITICAL:
> +		/*
> +		 * WARNING: Real-time busy loop takes priority on kernel threads,
> +		 *          making the system unstable.
> +		 *          There is also a known issue when using rte_ring.
> +		 */

I was thinking something like:

	static bool warned;
	if (!warned) {
		RTE_LOG(NOTICE, EAL, "Real time priority is unstable when thread is polling without sleep\n");
		warned = true;
	}