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Subject: Re: [TEGRA194_CPUFREQ Patch 2/3] cpufreq: Add Tegra194 cpufreq driver
To:     Viresh Kumar <viresh.kumar@linaro.org>
CC:     <rjw@rjwysocki.net>, <catalin.marinas@arm.com>, <will@kernel.org>,
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From:   Sumit Gupta <sumitg@nvidia.com>
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Date:   Thu, 16 Apr 2020 12:36:30 +0530
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On 16/04/20 9:07 AM, Viresh Kumar wrote:
> External email: Use caution opening links or attachments
> 
> 
> On 15-04-20, 16:55, Sumit Gupta wrote:
>>
>>
>> On 14/04/20 11:15 AM, Viresh Kumar wrote:
>>> External email: Use caution opening links or attachments
>>>
>>>
>>> On 13-04-20, 17:50, Sumit Gupta wrote:
>>>> This was done considering long delay value as explained previously.
>>>> Do you think that smp_call_function_single() would be better than work queue
>>>> here?
>>>
>>> Don't work with assumptions, you should test both and see which one
>>> works better. Workqueue should never be faster than
>>> smp_call_function_single() with my understanding.
>> Checked the time taken and its almost same in both cases.
>> Earlier we used smp_call_function_single(), but delay time period was small
>> in that SOC. In T194, the time period was more. So, this is an optimization
>> done because using work queue has advantage as interrupts will not be
>> disabled for that period.
> 
> Hmm, okay, keep the workqueue and mention the required details in a
> comment for everyone to understand why the implementation is done that
> way.
> 

sure, thank you!

> --
> viresh
>