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Date:   Wed, 21 Oct 2020 08:57:32 +0800
From:   Can Guo <cang@codeaurora.org>
To:     Jaegeuk Kim <jaegeuk@kernel.org>
Cc:     linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, kernel-team@android.com,
        Jaegeuk Kim <jaegeuk@google.com>,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Avri Altman <avri.altman@wdc.com>
Subject: Re: [PATCH v2 3/5] scsi: ufs: use WQ_HIGHPRI for gating work
In-Reply-To: <20201020195258.2005605-4-jaegeuk@kernel.org>
References: <20201020195258.2005605-1-jaegeuk@kernel.org>
 <20201020195258.2005605-4-jaegeuk@kernel.org>
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On 2020-10-21 03:52, Jaegeuk Kim wrote:
> From: Jaegeuk Kim <jaegeuk@google.com>
> 
> Must have WQ_MEM_RECLAIM
> ``WQ_MEM_RECLAIM``
>   All wq which might be used in the memory reclaim paths **MUST**
>   have this flag set.  The wq is guaranteed to have at least one
>   execution context regardless of memory pressure.
> 

You misunderstood my point. I meant you need to give more info about why
we are adding WQ_HIGHPRI flag but not why WQ_MEM_RECLAIM must be there.

Thanks,

Can Guo.

> Cc: Alim Akhtar <alim.akhtar@samsung.com>
> Cc: Avri Altman <avri.altman@wdc.com>
> Cc: Can Guo <cang@codeaurora.org>
> Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
> ---
>  drivers/scsi/ufs/ufshcd.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> index feb10ebf7a35..0858c0b55eac 100644
> --- a/drivers/scsi/ufs/ufshcd.c
> +++ b/drivers/scsi/ufs/ufshcd.c
> @@ -1867,7 +1867,7 @@ static void ufshcd_init_clk_gating(struct ufs_hba 
> *hba)
>  	snprintf(wq_name, ARRAY_SIZE(wq_name), "ufs_clk_gating_%d",
>  		 hba->host->host_no);
>  	hba->clk_gating.clk_gating_workq = alloc_ordered_workqueue(wq_name,
> -							   WQ_MEM_RECLAIM);
> +					WQ_MEM_RECLAIM | WQ_HIGHPRI);
> 
>  	hba->clk_gating.is_enabled = true;