RE: [PATCH v1] scsi: ufs: remove clk_scaling_lock when clkscaling isn't supported.

From: Kiwoong Kim
Date: Thu Feb 17 2022 - 03:15:26 EST


> On 2/14/22 22:03, Kiwoong Kim wrote:
> > The benefit that I think is not blocking dev cmd during submitting a
> scsi cmd.
>
> Hi Kiwoong,
>
> Both ufshcd_exec_dev_cmd() and previous versions of
> ufshcd_queuecommand() obtain a reader lock on the clock scaling lock so
> concurrent submission of both command types is allowed. I'm not aware of
> any version of the UFS driver that serializes device commands against SCSI
> commands.
>
> Additionally, please take a look at commit 8d077ede48c1 ("scsi: ufs:
> Optimize the command queueing code"). That patch removes the clock scaling
> lock from ufshcd_queuecommand().
>
> Thanks,
>
> Bart.

Okay, I got it.