2022-12-29 03:29:08

by Ed Tsai (蔡宗軒)

Subject: [PATCH 1/1] ufs: update the timeout timer after resume

The tags allocation is limited by the number of active queues and a
queue is marked as inactive by the queue timeout worker after up to 30Hz
by default.

Therefore, tags for the general I/O may be limited to half of the max
depth up to 30HZ after resume. To make sure the ufs request queue for pm
usage can be inactive immediately, trigger the timeout worker to release
the tag set.

Signed-off-by: Ed Tsai <[email protected]>
---
drivers/ufs/core/ufshcd.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
index e18c9f4463ec..c77570caa3a8 100644
--- a/drivers/ufs/core/ufshcd.c
+++ b/drivers/ufs/core/ufshcd.c
@@ -8842,6 +8842,7 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
hba->curr_dev_pwr_mode = pwr_mode;
}

+ mod_timer(&sdp->request_queue->timeout, 0);
scsi_device_put(sdp);
hba->host->eh_noresume = 0;
return ret;
--
2.18.0

2022-12-29 14:52:00

by Bart Van Assche

Subject: Re: [PATCH 1/1] ufs: update the timeout timer after resume

On 12/28/22 19:06, Ed Tsai wrote:
> The tags allocation is limited by the number of active queues and a
> queue is marked as inactive by the queue timeout worker after up to 30Hz
> by default.
>
> Therefore, tags for the general I/O may be limited to half of the max
> depth up to 30HZ after resume. To make sure the ufs request queue for pm
> usage can be inactive immediately, trigger the timeout worker to release
> the tag set.
>
> Signed-off-by: Ed Tsai <[email protected]>
> ---
> drivers/ufs/core/ufshcd.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/drivers/ufs/core/ufshcd.c b/drivers/ufs/core/ufshcd.c
> index e18c9f4463ec..c77570caa3a8 100644
> --- a/drivers/ufs/core/ufshcd.c
> +++ b/drivers/ufs/core/ufshcd.c
> @@ -8842,6 +8842,7 @@ static int ufshcd_set_dev_pwr_mode(struct ufs_hba *hba,
> hba->curr_dev_pwr_mode = pwr_mode;
> }
>
> + mod_timer(&sdp->request_queue->timeout, 0);
> scsi_device_put(sdp);
> hba->host->eh_noresume = 0;
> return ret;

Where is the code that restores the timeout to the original value?

Additionally, I think that only the block layer core should manipulate
the request queue timer directly. Please add a helper function in the
block layer and call that helper function from the UFS driver.

Thanks,

Bart.