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To:     Lu Hongfei <luhongfei@vivo.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
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CC:     "opensource.kernel@vivo.com" <opensource.kernel@vivo.com>
Subject: RE: [PATCH v4] scsi: ufs: wb: Add explicit flush_threshold sysfs
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Thread-Topic: [PATCH v4] scsi: ufs: wb: Add explicit flush_threshold sysfs
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Thread-Index: AQHZmrJi4hsth2Igeky+y402m8cNCq+CQbuw
Date:   Fri, 9 Jun 2023 10:18:07 +0000
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>=20
> There are three flags that control Write Booster Feature:
>=20
>     1. WB ON/OFF
>     2. WB Hibern Flush ON/OFF (implicitly)
>     3. WB Flush ON/OFF (explicit)
>=20
> In the case of "Hibern Flush", one of the conditions for flush WB buffer =
is
> that avail_wb_buff < wb_flush_threshold.
>=20
> As we know, different users have different requirements for power
> consumption and performance. Therefore, we need the ability to manually
> set wb_flush_threshold, so that users can easily and flexibly adjust
> the wb_flush_threshold value, thereby achieving a balance between power
> consumption and performance.
>=20
> So the sysfs attribute that controls this is necessary.
>=20
> The meaning of wb_flush_threshold is the percentage of WB's total size,
> such as 1 representing 10%, 2 representing 20%, and so on.
>=20
> Signed-off-by: Lu Hongfei <luhongfei@vivo.com>
Reviewed-by: Avri Altman <avri.altman@wdc.com>