RE: RE: [PATCH v5 05/10] scsi: ufshpb: Region inactivation in host mode

From: Daejun Park
Date: Tue Mar 16 2021 - 22:48:41 EST


>> >> ---
>> >> 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.

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 {
>
>
>