2020-12-13 18:59:03

by Can Guo

Subject: [PATCH v4 3/3] scsi: ufs: Revert "Make sure clk scaling happens only when HBA is runtime ACTIVE"

Commit 73cc291c27024 ("Make sure clk scaling happens only when HBA is
runtime ACTIVE") is no longer needed since commit f7a42540928a8 ("scsi:
ufs: Protect some contexts from unexpected clock scaling") is a more
mature fix to protect UFS LLD stability from clock scaling invoked through
sysfs nodes by users.

Signed-off-by: Can Guo <[email protected]>
---
drivers/scsi/ufs/ufshcd.c | 7 -------
1 file changed, 7 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 80f82cb..052479a 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1300,15 +1300,8 @@ static int ufshcd_devfreq_target(struct device *dev,
}
spin_unlock_irqrestore(hba->host->host_lock, irq_flags);

- pm_runtime_get_noresume(hba->dev);
- if (!pm_runtime_active(hba->dev)) {
- pm_runtime_put_noidle(hba->dev);
- ret = -EAGAIN;
- goto out;
- }
start = ktime_get();
ret = ufshcd_devfreq_scale(hba, scale_up);
- pm_runtime_put(hba->dev);

trace_ufshcd_profile_clk_scaling(dev_name(hba->dev),
(scale_up ? "up" : "down"),
--
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.

2020-12-15 06:18:56

by Stanley Chu

Subject: Re: [PATCH v4 3/3] scsi: ufs: Revert "Make sure clk scaling happens only when HBA is runtime ACTIVE"

On Sun, 2020-12-13 at 08:31 -0800, Can Guo wrote:
> Commit 73cc291c27024 ("Make sure clk scaling happens only when HBA is
> runtime ACTIVE") is no longer needed since commit f7a42540928a8 ("scsi:
> ufs: Protect some contexts from unexpected clock scaling") is a more
> mature fix to protect UFS LLD stability from clock scaling invoked through
> sysfs nodes by users.
>
> Signed-off-by: Can Guo <[email protected]>

Reviewed-by: Stanley Chu <[email protected]>