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    SubjectRE: Re: [PATCH v5 05/10] scsi: ufshpb: Region inactivation in host mode
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    >>>>>> >> ---
    >>>>>> >> drivers/scsi/ufs/ufshpb.c | 14 ++++++++++++++
    >>>>>> >> drivers/scsi/ufs/ufshpb.h | 1 +
    >>>>>> >> 2 files changed, 15 insertions(+)
    >>>>>> >>
    >>>>>> >> diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c
    >>>>>> >> index 6f4fd22eaf2f..0744feb4d484 100644
    >>>>>> >> --- a/drivers/scsi/ufs/ufshpb.c
    >>>>>> >> +++ b/drivers/scsi/ufs/ufshpb.c
    >>>>>> >> @@ -907,6 +907,7 @@ static int ufshpb_execute_umap_req(struct
    >>>>>> >> ufshpb_lu *hpb,
    >>>>>> >>
    >>>>>> >> blk_execute_rq_nowait(q, NULL, req, 1, ufshpb_umap_req_compl_fn);
    >>>>>> >>
    >>>>>> >> + hpb->stats.umap_req_cnt++;
    >>>>>> >> return 0;
    >>>>>> >> }
    >>>>>> >>
    >>>>>> >> @@ -1103,6 +1104,12 @@ static int ufshpb_issue_umap_req(struct
    >>>>>> >> ufshpb_lu *hpb,
    >>>>>> >> return -EAGAIN;
    >>>>>> >> }
    >>>>>> >>
    >>>>>> >> +static int ufshpb_issue_umap_single_req(struct ufshpb_lu *hpb,
    >>>>>> >> + struct ufshpb_region *rgn)
    >>>>>> >> +{
    >>>>>> >> + return ufshpb_issue_umap_req(hpb, rgn);
    >>>>>> >> +}
    >>>>>> >> +
    >>>>>> >> static int ufshpb_issue_umap_all_req(struct ufshpb_lu *hpb)
    >>>>>> >> {
    >>>>>> >> return ufshpb_issue_umap_req(hpb, NULL);
    >>>>>> >> @@ -1115,6 +1122,10 @@ static void __ufshpb_evict_region(struct
    >>>>>> >> ufshpb_lu *hpb,
    >>>>>> >> struct ufshpb_subregion *srgn;
    >>>>>> >> int srgn_idx;
    >>>>>> >>
    >>>>>> >> +
    >>>>>> >> + if (hpb->is_hcm && ufshpb_issue_umap_single_req(hpb, rgn))
    >>>>>> >
    >>>>>> > __ufshpb_evict_region() is called with rgn_state_lock held and IRQ
    >>>>>> > disabled,
    >>>>>> > when ufshpb_issue_umap_single_req() invokes blk_execute_rq_nowait(),
    >>>>>> > below
    >>>>>> > warning shall pop up every time, fix it?
    >>>>>> >
    >>>>>> > void blk_execute_rq_nowait(struct request_queue *q, struct gendisk
    >>>>>> > *bd_disk,
    >>>>>> > struct request *rq, int at_head,
    >>>>>> > rq_end_io_fn *done)
    >>>>>> > {
    >>>>>> > WARN_ON(irqs_disabled());
    >>>>>> > ...
    >>>>>> >
    >>>>>>
    >>>>>> Moreover, since we are here with rgn_state_lock held and IRQ
    >>>>>> disabled,
    >>>>>> in ufshpb_get_req(), rq = kmem_cache_alloc(hpb->map_req_cache,
    >>>>>> GFP_KERNEL)
    >>>>>> has the GFP_KERNEL flag, scheduling while atomic???
    >>>>> I think your comment applies to ufshpb_issue_umap_all_req as well,
    >>>>> Which is called from slave_configure/scsi_add_lun.
    >>>>>
    >>>>> Since the host-mode series is utilizing the framework laid by the
    >>>>> device-mode,
    >>>>> Maybe you can add this comment to Daejun's last version?
    >>>>
    >>>> Hi Avri, Can Guo
    >>>>
    >>>> I think ufshpb_issue_umap_single_req() can be moved to end of
    >>>> ufshpb_evict_region().
    >>>> Then we can avoid rgn_state_lock when it sends unmap command.
    >>>
    >>> I am not the expert here, please you two fix it. I am just reporting
    >>> what can be wrong. Anyways, ufshpb_issue_umap_single_req() should not
    >>> be called with rgn_state_lock held - think about below (another
    >>> deadly)
    >>> scenario.
    >>>
    >>> lock(rgn_state_lock)
    >>> ufshpb_issue_umap_single_req()
    >>> ufshpb_prep()
    >>> lock(rgn_state_lock) <---------- recursive spin_lock
    >>>
    >>> BTW, @Daejun shouldn't we stop passthrough cmds from stepping
    >>> into ufshpb_prep()? In current code, you are trying to use below
    >>> check to block cmds other than write/discard/read, but a passthrough
    >>> cmd can not be blocked by the check.
    >>>
    >>> if (!ufshpb_is_write_or_discard_cmd(cmd) &&
    >>> !ufshpb_is_read_cmd(cmd) )
    >>> return 0;
    >>
    >> I found this problem too. I fixed it and submit next patch.
    >
    >You mean in V30, which has not been uploaded yet, right?

    Yes, it is about v30.

    Thanks,
    Daejun

    >Thanks,
    >Can Guo.
    >
    >>
    >> if (blk_rq_is_scsi(cmd->request) ||
    >> (!ufshpb_is_write_or_discard_cmd(cmd) &&
    >> !ufshpb_is_read_cmd(cmd)))
    >> return 0;
    >>
    >>
    >> Thanks,
    >> Daejun
    >>
    >>> Thanks,
    >>> Can Guo.
    >>>
    >>>>
    >>>> Thanks,
    >>>> Daejun
    >>>>
    >>>>
    >>>>> Thanks,
    >>>>> Avri
    >>>>>
    >>>>>>
    >>>>>> Can Guo.
    >>>>>>
    >>>>>> > Thanks.
    >>>>>> > Can Guo.
    >>>>>> >
    >>>>>> >> + return;
    >>>>>> >> +
    >>>>>> >> lru_info = &hpb->lru_info;
    >>>>>> >>
    >>>>>> >> dev_dbg(&hpb->sdev_ufs_lu->sdev_dev, "evict region %d\n",
    >>>>>> >> rgn->rgn_idx);
    >>>>>> >> @@ -1855,6 +1866,7 @@ ufshpb_sysfs_attr_show_func(rb_noti_cnt);
    >>>>>> >> ufshpb_sysfs_attr_show_func(rb_active_cnt);
    >>>>>> >> ufshpb_sysfs_attr_show_func(rb_inactive_cnt);
    >>>>>> >> ufshpb_sysfs_attr_show_func(map_req_cnt);
    >>>>>> >> +ufshpb_sysfs_attr_show_func(umap_req_cnt);
    >>>>>> >>
    >>>>>> >> static struct attribute *hpb_dev_stat_attrs[] = {
    >>>>>> >> &dev_attr_hit_cnt.attr,
    >>>>>> >> @@ -1863,6 +1875,7 @@ static struct attribute *hpb_dev_stat_attrs[] =
    >>>>>> >> {
    >>>>>> >> &dev_attr_rb_active_cnt.attr,
    >>>>>> >> &dev_attr_rb_inactive_cnt.attr,
    >>>>>> >> &dev_attr_map_req_cnt.attr,
    >>>>>> >> + &dev_attr_umap_req_cnt.attr,
    >>>>>> >> NULL,
    >>>>>> >> };
    >>>>>> >>
    >>>>>> >> @@ -1978,6 +1991,7 @@ static void ufshpb_stat_init(struct ufshpb_lu
    >>>>>> >> *hpb)
    >>>>>> >> hpb->stats.rb_active_cnt = 0;
    >>>>>> >> hpb->stats.rb_inactive_cnt = 0;
    >>>>>> >> hpb->stats.map_req_cnt = 0;
    >>>>>> >> + hpb->stats.umap_req_cnt = 0;
    >>>>>> >> }
    >>>>>> >>
    >>>>>> >> static void ufshpb_param_init(struct ufshpb_lu *hpb)
    >>>>>> >> diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h
    >>>>>> >> index bd4308010466..84598a317897 100644
    >>>>>> >> --- a/drivers/scsi/ufs/ufshpb.h
    >>>>>> >> +++ b/drivers/scsi/ufs/ufshpb.h
    >>>>>> >> @@ -186,6 +186,7 @@ struct ufshpb_stats {
    >>>>>> >> u64 rb_inactive_cnt;
    >>>>>> >> u64 map_req_cnt;
    >>>>>> >> u64 pre_req_cnt;
    >>>>>> >> + u64 umap_req_cnt;
    >>>>>> >> };
    >>>>>> >>
    >>>>>> >> struct ufshpb_lu {
    >>>>>
    >>>>>
    >>>>>
    >>>
    >>>
    >>>
    >
    >
    >

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