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From:   Avri Altman <Avri.Altman@wdc.com>
To:     Ed Tsai <ed.tsai@mediatek.com>, "axboe@kernel.dk" <axboe@kernel.dk>
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Subject: RE: [PATCH 2/2] ufs: don't use the fair tag sharings
Thread-Topic: [PATCH 2/2] ufs: don't use the fair tag sharings
Thread-Index: AQHZgkMMEfz/mkmxPE2tTXnep9Miz69RlGFw
Date:   Tue, 9 May 2023 08:03:01 +0000
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References: <20230509065230.32552-1-ed.tsai@mediatek.com>
 <20230509065230.32552-3-ed.tsai@mediatek.com>
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=20
> The tags allocation is limited by the fair sharing algorithm. It hurts
> the performance for UFS devices, because the queue depth of general I/O
> is reduced by half once the UFS send a control command.
Ack.

However, I think the decision of that should be of the platform owner,
And not in the core driver.

Thanks,
Avri

>=20
> Signed-off-by: Ed Tsai <ed.tsai@mediatek.com>
> ---
>  drivers/ufs/core/ufshcd.c | 3 +++
>  1 file changed, 3 insertions(+)
>=20
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index 17d7bb875fee..e96a50265285 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -5149,6 +5149,9 @@ static int ufshcd_slave_configure(struct scsi_devic=
e
> *sdev)
>         blk_queue_update_dma_pad(q, PRDT_DATA_BYTE_COUNT_PAD - 1);
>         if (hba->quirks & UFSHCD_QUIRK_4KB_DMA_ALIGNMENT)
>                 blk_queue_update_dma_alignment(q, 4096 - 1);
> +
> +       blk_queue_flag_clear(QUEUE_FLAG_FAIR_TAG_SHARING, q);
> +
>         /*
>          * Block runtime-pm until all consumers are added.
>          * Refer ufshcd_setup_links().
> --
> 2.18.0