2020-10-21 09:57:18

by Jaegeuk Kim

Subject: [PATCH v2 3/5] scsi: ufs: use WQ_HIGHPRI for gating work

From: Jaegeuk Kim <[email protected]>

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.

Cc: Alim Akhtar <[email protected]>
Cc: Avri Altman <[email protected]>
Cc: Can Guo <[email protected]>
Signed-off-by: Jaegeuk Kim <[email protected]>
---
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;

--
2.29.0.rc1.297.gfa9743e501-goog

2020-10-21 11:58:14

by Can Guo

Subject: Re: [PATCH v2 3/5] scsi: ufs: use WQ_HIGHPRI for gating work

On 2020-10-21 03:52, Jaegeuk Kim wrote:
> From: Jaegeuk Kim <[email protected]>
>
> 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 <[email protected]>
> Cc: Avri Altman <[email protected]>
> Cc: Can Guo <[email protected]>
> Signed-off-by: Jaegeuk Kim <[email protected]>
> ---
> 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;

2020-10-21 18:40:09

by Jaegeuk Kim

Subject: Re: [PATCH v2 3/5] scsi: ufs: use WQ_HIGHPRI for gating work

On 10/21, Can Guo wrote:
> On 2020-10-21 03:52, Jaegeuk Kim wrote:
> > From: Jaegeuk Kim <[email protected]>
> >
> > 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.

Oh, I thought that WQ_HIGHPRI is telling everything tho.

>
> Thanks,
>
> Can Guo.
>
> > Cc: Alim Akhtar <[email protected]>
> > Cc: Avri Altman <[email protected]>
> > Cc: Can Guo <[email protected]>
> > Signed-off-by: Jaegeuk Kim <[email protected]>
> > ---
> > 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;