RE: [PATCH v5 03/10] scsi: ufshpb: Add region's reads counter

[Avri Altman]

> > +
> > +             if (hpb->is_hcm) {
> > +                     spin_lock_irqsave(&rgn->rgn_lock, flags);
> 
> rgn_lock is never used in IRQ contexts, so no need of irqsave and
> irqrestore everywhere, which can impact performance. Please correct
> me if I am wrong.
Thanks.  Will do.

> 
> Meanwhile, have you ever initialized the rgn_lock before use it???
Yep - forgot to do that here (but not in gs20 and mi10).  Thanks.

Thanks,
Avri

> 
> Thanks,
> Can Guo.
> 
> > +                     rgn->reads = 0;
> > +                     spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> > +             }
> > +
> >               return 0;
> >       }
> >
> >       if (!ufshpb_is_support_chunk(hpb, transfer_len))
> >               return 0;
> >
> > +     if (hpb->is_hcm) {
> > +             bool activate = false;
> > +             /*
> > +              * in host control mode, reads are the main source for
> > +              * activation trials.
> > +              */
> > +             spin_lock_irqsave(&rgn->rgn_lock, flags);
> > +             rgn->reads++;
> > +             if (rgn->reads == ACTIVATION_THRESHOLD)
> > +                     activate = true;
> > +             spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> > +             if (activate) {
> > +                     spin_lock_irqsave(&hpb->rsp_list_lock, flags);
> > +                     ufshpb_update_active_info(hpb, rgn_idx, srgn_idx);
> > +                     hpb->stats.rb_active_cnt++;
> > +                     spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
> > +                     dev_dbg(&hpb->sdev_ufs_lu->sdev_dev,
> > +                             "activate region %d-%d\n", rgn_idx, srgn_idx);
> > +             }
> > +
> > +             /* keep those counters normalized */
> > +             if (rgn->reads > hpb->entries_per_srgn)
> > +                     schedule_work(&hpb->ufshpb_normalization_work);
> > +     }
> > +
> >       spin_lock_irqsave(&hpb->rgn_state_lock, flags);
> >       if (ufshpb_test_ppn_dirty(hpb, rgn_idx, srgn_idx, srgn_offset,
> >                                  transfer_len)) {
> > @@ -745,21 +794,6 @@ static int ufshpb_clear_dirty_bitmap(struct
> > ufshpb_lu *hpb,
> >       return 0;
> >  }
> >
> > -static void ufshpb_update_active_info(struct ufshpb_lu *hpb, int
> > rgn_idx,
> > -                                   int srgn_idx)
> > -{
> > -     struct ufshpb_region *rgn;
> > -     struct ufshpb_subregion *srgn;
> > -
> > -     rgn = hpb->rgn_tbl + rgn_idx;
> > -     srgn = rgn->srgn_tbl + srgn_idx;
> > -
> > -     list_del_init(&rgn->list_inact_rgn);
> > -
> > -     if (list_empty(&srgn->list_act_srgn))
> > -             list_add_tail(&srgn->list_act_srgn, &hpb->lh_act_srgn);
> > -}
> > -
> >  static void ufshpb_update_inactive_info(struct ufshpb_lu *hpb, int
> > rgn_idx)
> >  {
> >       struct ufshpb_region *rgn;
> > @@ -1079,6 +1113,14 @@ static void __ufshpb_evict_region(struct
> > ufshpb_lu *hpb,
> >
> >       ufshpb_cleanup_lru_info(lru_info, rgn);
> >
> > +     if (hpb->is_hcm) {
> > +             unsigned long flags;
> > +
> > +             spin_lock_irqsave(&rgn->rgn_lock, flags);
> > +             rgn->reads = 0;
> > +             spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> > +     }
> > +
> >       for_each_sub_region(rgn, srgn_idx, srgn)
> >               ufshpb_purge_active_subregion(hpb, srgn);
> >  }
> > @@ -1523,6 +1565,31 @@ static void
> > ufshpb_run_inactive_region_list(struct ufshpb_lu *hpb)
> >       spin_unlock_irqrestore(&hpb->rsp_list_lock, flags);
> >  }
> >
> > +static void ufshpb_normalization_work_handler(struct work_struct
> > *work)
> > +{
> > +     struct ufshpb_lu *hpb;
> > +     int rgn_idx;
> > +     unsigned long flags;
> > +
> > +     hpb = container_of(work, struct ufshpb_lu,
> > ufshpb_normalization_work);
> > +
> > +     for (rgn_idx = 0; rgn_idx < hpb->rgns_per_lu; rgn_idx++) {
> > +             struct ufshpb_region *rgn = hpb->rgn_tbl + rgn_idx;
> > +
> > +             spin_lock_irqsave(&rgn->rgn_lock, flags);
> > +             rgn->reads = (rgn->reads >> 1);
> > +             spin_unlock_irqrestore(&rgn->rgn_lock, flags);
> > +
> > +             if (rgn->rgn_state != HPB_RGN_ACTIVE || rgn->reads)
> > +                     continue;
> > +
> > +             /* if region is active but has no reads - inactivate it */
> > +             spin_lock(&hpb->rsp_list_lock);
> > +             ufshpb_update_inactive_info(hpb, rgn->rgn_idx);
> > +             spin_unlock(&hpb->rsp_list_lock);
> > +     }
> > +}
> > +
> >  static void ufshpb_map_work_handler(struct work_struct *work)
> >  {
> >       struct ufshpb_lu *hpb = container_of(work, struct ufshpb_lu,
> > map_work);
> > @@ -1913,6 +1980,9 @@ 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)
> > +             INIT_WORK(&hpb->ufshpb_normalization_work,
> > +                       ufshpb_normalization_work_handler);
> >
> >       hpb->map_req_cache = kmem_cache_create("ufshpb_req_cache",
> >                         sizeof(struct ufshpb_req), 0, 0, NULL);
> > @@ -2012,6 +2082,8 @@ static void ufshpb_discard_rsp_lists(struct
> > ufshpb_lu *hpb)
> >
> >  static void ufshpb_cancel_jobs(struct ufshpb_lu *hpb)
> >  {
> > +     if (hpb->is_hcm)
> > +             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 8119b1a3d1e5..bd4308010466 100644
> > --- a/drivers/scsi/ufs/ufshpb.h
> > +++ b/drivers/scsi/ufs/ufshpb.h
> > @@ -121,6 +121,10 @@ struct ufshpb_region {
> >       struct list_head list_lru_rgn;
> >       unsigned long rgn_flags;
> >  #define RGN_FLAG_DIRTY 0
> > +
> > +     /* region reads - for host mode */
> > +     spinlock_t rgn_lock;
> > +     unsigned int reads;
> >  };
> >
> >  #define for_each_sub_region(rgn, i, srgn)                            \
> > @@ -211,6 +215,7 @@ struct ufshpb_lu {
> >
> >       /* for selecting victim */
> >       struct victim_select_info lru_info;
> > +     struct work_struct ufshpb_normalization_work;
> >
> >       /* pinned region information */
> >       u32 lu_pinned_start;