RE: [PATCH v5 06/10] scsi: ufshpb: Add hpb dev reset response

[Avri Altman <Avri.Altman@wdc.com>]

> 
> On 2021-03-02 21:24, Avri Altman wrote:
> > The spec does not define what is the host's recommended response when
> > the device send hpb dev reset response (oper 0x2).
> >
> > We will update all active hpb regions: mark them and do that on the
> > next
> > read.
> >
> > Signed-off-by: Avri Altman <avri.altman@wdc.com>
> > ---
> >  drivers/scsi/ufs/ufshpb.c | 47
> ++++++++++++++++++++++++++++++++++++---
> >  drivers/scsi/ufs/ufshpb.h |  2 ++
> >  2 files changed, 46 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
> > index 0744feb4d484..0034fa03fdc6 100644
> > --- a/drivers/scsi/ufs/ufshpb.c
> > +++ b/drivers/scsi/ufs/ufshpb.c
> > @@ -642,7 +642,8 @@ int ufshpb_prep(struct ufs_hba *hba, struct
> > ufshcd_lrb *lrbp)
> >               if (rgn->reads == ACTIVATION_THRESHOLD)
> >                       activate = true;
> >               spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> > -             if (activate) {
> > +             if (activate ||
> > +                 test_and_clear_bit(RGN_FLAG_UPDATE, &rgn->rgn_flags)) {
> >                       spin_lock_irqsave(&hpb->rsp_list_lock, flags);
> >                       ufshpb_update_active_info(hpb, rgn_idx, srgn_idx);
> >                       hpb->stats.rb_active_cnt++;
> > @@ -1480,6 +1481,20 @@ void ufshpb_rsp_upiu(struct ufs_hba *hba,
> > struct ufshcd_lrb *lrbp)
> >       case HPB_RSP_DEV_RESET:
> >               dev_warn(&hpb->sdev_ufs_lu->sdev_dev,
> >                        "UFS device lost HPB information during PM.\n");
> > +
> > +             if (hpb->is_hcm) {
> > +                     struct scsi_device *sdev;
> > +
> > +                     __shost_for_each_device(sdev, hba->host) {
> > +                             struct ufshpb_lu *h = sdev->hostdata;
> > +
> > +                             if (!h)
> > +                                     continue;
> > +
> > +                             schedule_work(&hpb->ufshpb_lun_reset_work);
> > +                     }
> > +             }
> > +
> >               break;
> >       default:
> >               dev_notice(&hpb->sdev_ufs_lu->sdev_dev,
> > @@ -1594,6 +1609,25 @@ static void
> > ufshpb_run_inactive_region_list(struct ufshpb_lu *hpb)
> >       spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
> >  }
> >
> > +static void ufshpb_reset_work_handler(struct work_struct *work)
> 
> Just curious, directly doing below things inside ufshpb_rsp_upiu() does
> not
> seem a problem to me, does this really deserve a separate work?
I don't know, I never even consider of doing this.
The active region list may contain up to few thousands of regions - 
It is not rare to see configurations that covers the entire device.

But yes, I can do that.
Better to get ack from Daejun first.

Thanks,
Avri

> 
> Thanks,
> Can Guo.
> 
> > +{
> > +     struct ufshpb_lu *hpb;
> > +     struct victim_select_info *lru_info;
> > +     struct ufshpb_region *rgn;
> > +     unsigned long flags;
> > +
> > +     hpb = container_of(work, struct ufshpb_lu, ufshpb_lun_reset_work);
> > +
> > +     lru_info = &hpb->lru_info;
> > +
> > +     spin_lock_irqsave(&hpb->rgn_state_lock, flags);
> > +
> > +     list_for_each_entry(rgn, &lru_info->lh_lru_rgn, list_lru_rgn)
> > +             set_bit(RGN_FLAG_UPDATE, &rgn->rgn_flags);
> > +
> > +     spin_unlock_irqrestore(&hpb->rgn_state_lock, flags);
> > +}
> > +
> >  static void ufshpb_normalization_work_handler(struct work_struct
> > *work)
> >  {
> >       struct ufshpb_lu *hpb;
> > @@ -1798,6 +1832,8 @@ static int ufshpb_alloc_region_tbl(struct
> > ufs_hba *hba, struct ufshpb_lu *hpb)
> >               } else {
> >                       rgn->rgn_state = HPB_RGN_INACTIVE;
> >               }
> > +
> > +             rgn->rgn_flags = 0;
> >       }
> >
> >       return 0;
> > @@ -2012,9 +2048,12 @@ static int ufshpb_lu_hpb_init(struct ufs_hba
> > *hba, struct ufshpb_lu *hpb)
> >       INIT_LIST_HEAD(&hpb->list_hpb_lu);
> >
> >       INIT_WORK(&hpb->map_work, ufshpb_map_work_handler);
> > -     if (hpb->is_hcm)
> > +     if (hpb->is_hcm) {
> >               INIT_WORK(&hpb->ufshpb_normalization_work,
> >                         ufshpb_normalization_work_handler);
> > +             INIT_WORK(&hpb->ufshpb_lun_reset_work,
> > +                       ufshpb_reset_work_handler);
> > +     }
> >
> >       hpb->map_req_cache = kmem_cache_create("ufshpb_req_cache",
> >                         sizeof(struct ufshpb_req), 0, 0, NULL);
> > @@ -2114,8 +2153,10 @@ static void ufshpb_discard_rsp_lists(struct
> > ufshpb_lu *hpb)
> >
> >  static void ufshpb_cancel_jobs(struct ufshpb_lu *hpb)
> >  {
> > -     if (hpb->is_hcm)
> > +     if (hpb->is_hcm) {
> > +             cancel_work_sync(&hpb->ufshpb_lun_reset_work);
> >               cancel_work_sync(&hpb->ufshpb_normalization_work);
> > +     }
> >       cancel_work_sync(&hpb->map_work);
> >  }
> >
> > diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
> > index 84598a317897..37c1b0ea0c0a 100644
> > --- a/drivers/scsi/ufs/ufshpb.h
> > +++ b/drivers/scsi/ufs/ufshpb.h
> > @@ -121,6 +121,7 @@ struct ufshpb_region {
> >       struct list_head list_lru_rgn;
> >       unsigned long rgn_flags;
> >  #define RGN_FLAG_DIRTY 0
> > +#define RGN_FLAG_UPDATE 1
> >
> >       /* region reads - for host mode */
> >       spinlock_t rgn_lock;
> > @@ -217,6 +218,7 @@ struct ufshpb_lu {
> >       /* for selecting victim */
> >       struct victim_select_info lru_info;
> >       struct work_struct ufshpb_normalization_work;
> > +     struct work_struct ufshpb_lun_reset_work;
> >
> >       /* pinned region information */
> >       u32 lu_pinned_start;