RE:(2) [PATCH] scsi: ufs: Optimize the WB flush process to save device power consumption

[Jinyoung CHOI]

>> 
>> In the original logic, WB Hibern Flush was always on.
>> During suspend flow, the host will determine whether the device needs
>> BKOP or WB flush, and if so, it will keep VCC supply.
>> WB flush is only a part of BKOP, and device that needs BKOP do not
>> necessarily need WB flush if the conditions are not met. Therefore,
>> if WB flush is not needed, it will be better to disable WB Hibern
>> Flush,..... 
>I beg to differ on this conclusion.
>If you expect SLC write performance, without fluctuations,
>the host should let the device manage its wb buffer on its own.
>This is exactly what flush on hibernate does and better leave it be.
>
>Thanks,
>Avri

Hi, Lu Hongfei.

I agree with avri.
In fact, I am not sure if there will be a significant improvement in
power consumption.
In addition, for the toggle of the function, a code that compares with
the existing value must be added to prevent unnecessary queries.

Best Regards,
Jinyoung.