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Message-ID: <a5160a37-7778-49ff-8c25-92846d42e87e@intel.com>
Date:   Thu, 2 Nov 2023 10:57:46 -0700
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 24/24] selftests/resctrl: Ignore failures from L2 CAT test
 with <= 2 bits
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To:     =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>,
        <linux-kselftest@vger.kernel.org>, Shuah Khan <shuah@kernel.org>,
        "Shaopeng Tan" <tan.shaopeng@jp.fujitsu.com>,
        =?UTF-8?Q?Maciej_Wiecz=C3=B3r-Retman?= 
        <maciej.wieczor-retman@intel.com>,
        Fenghua Yu <fenghua.yu@intel.com>
CC:     <linux-kernel@vger.kernel.org>
References: <20231024092634.7122-1-ilpo.jarvinen@linux.intel.com>
 <20231024092634.7122-25-ilpo.jarvinen@linux.intel.com>
From:   Reinette Chatre <reinette.chatre@intel.com>
In-Reply-To: <20231024092634.7122-25-ilpo.jarvinen@linux.intel.com>
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Hi Ilpo,

On 10/24/2023 2:26 AM, Ilpo Järvinen wrote:
> L2 CAT test with low number of bits tends to occasionally fail because
> of what seems random variation. The margin is quite small to begin with
> for <= 2 bits in CBM. At times, the result can even become negative.
> While it would be possible to allow negative values for those cases, it
> would be more confusing to user.
> 
> Ignore failures from the tests where <= 2 were used to avoid false
> negative results.
> 

I think the core message is that 2 or fewer bits should not be used. Instead
of running the test and ignoring the results the test should perhaps just not
be run.

Reinette