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Subject: Re: [PATCH 1/3] Tunables: Add tunables of spin count for adaptive
 spin mutex
To: Adhemerval Zanella <adhemerval.zanella@linaro.org>,
 kemi <kemi.wang@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>, Tim Chen
 <tim.c.chen@intel.com>, Andi Kleen <andi.kleen@intel.com>,
 Ying Huang <ying.huang@intel.com>, Aaron Lu <aaron.lu@intel.com>,
 Glibc alpha <libc-alpha@sourceware.org>, aubrey <aubrey.li@intel.com>
References: <1522394093-9835-1-git-send-email-kemi.wang@intel.com>
 <03d60e93-a167-1401-b67e-22d7d2443486@intel.com>
 <f65e64f5-7289-faa4-2314-71ce5e904bf0@linaro.org>
From: Carlos O'Donell <carlos@redhat.com>
Message-ID: <e1f5530c-b7eb-55ba-1784-3032ce657939@redhat.com>
Date: Thu, 05 Apr 2018 01:11:00 -0000
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On 04/04/2018 12:16 PM, Adhemerval Zanella wrote:
>>> Also I not sure if it worth to add environment variable for this tunable,
>>> I would rather avoid adding newer ones (and naming seems off, since afaik
>>> LD_* meaning some parameters that affects the loader).
>>>
>>
>> AFAIK, environment variable is what I can think of to give people the possibility of 
>> tunes in shell for that, maybe you have better idea?
>>
>> Yes, we probably use other name like MUTEX_SPIN_COUNT to avoid confusion, agree?
> 
> The tunables framework already provides a environment variable to this [1],
> the 'env_alias' is mainly to provide compatibility and to use the same logic
> internally.
> 
> So I think it is better to use the default tunable env var.
> 
> [1] https://www.gnu.org/software/libc/manual/html_node/Tunables.html

Fully agree. We should never add any new environment variable, they should all be
automatically used from the top-level tunable env var.

-- 
Cheers,
Carlos.