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

Bart Van Assche
2022-02-15T17:15:48Z

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.