Re: [PATCH v2 1/3] scsi: ufs: Minor adjustments to error handling

[Can Guo <cang@xxxxxxxxxxxxxx>]

Hi Avri,

On 2021-03-03 15:22, Avri Altman wrote:
> > In error handling prepare stage, after SCSI requests are blocked, do a
> > down/up_write(clk_scaling_lock) to clean up the queuecommand() path.
> > Meanwhile, stop eeh_work in case it disturbs error recovery. Moreover,
> > reset ufshcd_state at the entrance of ufshcd_probe_hba(), since it may 
> > be
> > called multiple times during error recovery.
> >
> > Signed-off-by: Can Guo <cang@xxxxxxxxxxxxxx>
> I noticed that you tagged Adrian's patch -
> https://lore.kernel.org/lkml/20210301191940.15247-1-adrian.hunter@xxxxxxxxx/
> So this patch needs to be adjusted accordingly?

Thanks for pointing me to that one, I will rebase mine.

Regards,
Can Guo.

> Thanks,
> Avri
>
> > ---
> >  drivers/scsi/ufs/ufshcd.c | 18 ++++++++++++------
> >  1 file changed, 12 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
> > index 80620c8..013eb73 100644
> > --- a/drivers/scsi/ufs/ufshcd.c
> > +++ b/drivers/scsi/ufs/ufshcd.c
> > @@ -4987,6 +4987,7 @@ ufshcd_transfer_rsp_status(struct ufs_hba *hba,
> > struct ufshcd_lrb *lrbp)
> >                          * UFS device needs urgent BKOPs.
> >                          */
> >                         if (!hba->pm_op_in_progress &&
> > +                           !ufshcd_eh_in_progress(hba) &&
> >                             
> > ufshcd_is_exception_event(lrbp->ucd_rsp_ptr) &&
> >                             schedule_work(&hba->eeh_work)) {
> >                                 /*
> > @@ -5784,13 +5785,20 @@ static void ufshcd_err_handling_prepare(struct
> > ufs_hba *hba)
> >                         ufshcd_suspend_clkscaling(hba);
> >                 ufshcd_clk_scaling_allow(hba, false);
> >         }
> > +       ufshcd_scsi_block_requests(hba);
> > +       /* Drain ufshcd_queuecommand() */
> > +       down_write(&hba->clk_scaling_lock);
> > +       up_write(&hba->clk_scaling_lock);
> > +       cancel_work_sync(&hba->eeh_work);
> >  }
> >
> >  static void ufshcd_err_handling_unprepare(struct ufs_hba *hba)
> >  {
> > +       ufshcd_scsi_unblock_requests(hba);
> >         ufshcd_release(hba);
> >         if (ufshcd_is_clkscaling_supported(hba))
> >                 ufshcd_clk_scaling_suspend(hba, false);
> > +       ufshcd_clear_ua_wluns(hba);
> >         pm_runtime_put(hba->dev);
> >  }
> >
> > @@ -5882,8 +5890,8 @@ static void ufshcd_err_handler(struct 
> > work_struct
> > *work)
> >         spin_unlock_irqrestore(hba->host->host_lock, flags);
> >         ufshcd_err_handling_prepare(hba);
> >         spin_lock_irqsave(hba->host->host_lock, flags);
> > -       ufshcd_scsi_block_requests(hba);
> > -       hba->ufshcd_state = UFSHCD_STATE_RESET;
> > +       if (hba->ufshcd_state != UFSHCD_STATE_ERROR)
> > +               hba->ufshcd_state = UFSHCD_STATE_RESET;
> >
> >         /* Complete requests that have door-bell cleared by h/w */
> >         ufshcd_complete_requests(hba);
> > @@ -6042,12 +6050,8 @@ static void ufshcd_err_handler(struct 
> > work_struct
> > *work)
> >         }
> >         ufshcd_clear_eh_in_progress(hba);
> >         spin_unlock_irqrestore(hba->host->host_lock, flags);
> > -       ufshcd_scsi_unblock_requests(hba);
> >         ufshcd_err_handling_unprepare(hba);
> >         up(&hba->host_sem);
> > -
> > -       if (!err && needs_reset)
> > -               ufshcd_clear_ua_wluns(hba);
> >  }
> >
> >  /**
> > @@ -7858,6 +7862,8 @@ static int ufshcd_probe_hba(struct ufs_hba *hba,
> > bool async)
> >         unsigned long flags;
> >         ktime_t start = ktime_get();
> >
> > +       hba->ufshcd_state = UFSHCD_STATE_RESET;
> > +
> >         ret = ufshcd_link_startup(hba);
> >         if (ret)
> >                 goto out;
> > --
> > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a 
> > Linux
> > Foundation Collaborative Project.