scsi: ufs: fix rpm racing issue

PATCH In review [email protected] 2 participants 3 messages Apr 21, 2022 – Apr 26, 2022

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SCSI Arm MediaTek

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2022-04-21 14:42 UTC #0 lore raw

PATCH 1/1 scsi: ufs: fix rpm racing issue

From: Peter Wang <[email protected]>

Device WLun may enter RPM_SUSPENDED and the consumer is RPM_ACTIVE.

The error state is
Device Wlun RPM: status:2, usage_count:0
Consumer: 0:0:0:49476 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:49456 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:0 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:1 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:2 Link: rpm_active:1, RPM: status:0, usage_count:0

Because rpm enable before rpm delay set, scsi_autopm_put_device invoke by scsi_sysfs_add_sdev may cause consumer enter suspend immediately. Thas will always set rpm_active to 1.
If driver_probe_device invoke pm_runtime_get_suppliers just befor previous scsi_autopm_put_device, the rpm_active will change to 1 after pm_runtime_put_suppliers.
Set this delay to avoid scsi_autopm_put_device enter suspend immediately.

Signed-off-by Peter Wang <[email protected]>

---
 drivers/scsi/ufs/ufshcd.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

drivers/scsi/ufs/ufshcd.c +6 -2

index 3f9caafa91bf..1250792d16be 100644
@@ -5024,10 +5024,14 @@ static int ufshcd_slave_configure(struct scsi_device *sdev)
 	 * Block runtime-pm until all consumers are added.
 	 * Refer ufshcd_setup_links().
 	 */
-	if (is_device_wlun(sdev))
+	if (is_device_wlun(sdev)) {
 		pm_runtime_get_noresume(&sdev->sdev_gendev);
-	else if (ufshcd_is_rpm_autosuspend_allowed(hba))
+	} else if (ufshcd_is_rpm_autosuspend_allowed(hba)) {
 		sdev->rpm_autosuspend = 1;
+		pm_runtime_set_autosuspend_delay(&sdev->sdev_gendev,
+			RPM_AUTOSUSPEND_DELAY_MS);
+	}
+
 	/*
 	 * Do not print messages during runtime PM to avoid never-ending cycles
 	 * of messages written back to storage by user space causing runtime

Signature · 1 line

2.18.0

Avri Altman

2022-04-25 08:36 UTC #1 lore raw

Quoted 35 lines

From: Peter Wang <[email protected]>
Device WLun may enter RPM_SUSPENDED and the consumer is RPM_ACTIVE.
The error state is
Device Wlun RPM: status:2, usage_count:0
Consumer: 0:0:0:49476 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:49456 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:0 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:1 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:2 Link: rpm_active:1, RPM: status:0, usage_count:0
Because rpm enable before rpm delay set, scsi_autopm_put_device invoke by scsi_sysfs_add_sdev may cause consumer enter suspend immediately.
Thas will always set rpm_active to 1.
If driver_probe_device invoke pm_runtime_get_suppliers just befor previous scsi_autopm_put_device, the rpm_active will change to 1 after pm_runtime_put_suppliers.
Set this delay to avoid scsi_autopm_put_device enter suspend immediately.
Signed-off-by Peter Wang <[email protected]>
---
 drivers/scsi/ufs/ufshcd.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)
drivers/scsi/ufs/ufshcd.c +0 -0
index 3f9caafa91bf..1250792d16be 100644
@@ -5024,10 +5024,14 @@ static int ufshcd_slave_configure(struct
 scsi_device *sdev)
         * Block runtime-pm until all consumers are added.
         * Refer ufshcd_setup_links().

drivers/scsi/ufs/ufshcd.c static int ufshcd_slave_configure(struct · line 5034

Quoted 10 lines

drivers/scsi/ufs/ufshcd.c +5 -2

         */
-       if (is_device_wlun(sdev))
+       if (is_device_wlun(sdev)) {
                pm_runtime_get_noresume(&sdev->sdev_gendev);
-       else if (ufshcd_is_rpm_autosuspend_allowed(hba))
+       } else if (ufshcd_is_rpm_autosuspend_allowed(hba)) {
                sdev->rpm_autosuspend = 1;
+               pm_runtime_set_autosuspend_delay(&sdev->sdev_gendev,
+                       RPM_AUTOSUSPEND_DELAY_MS);
+       }

Maybe remove ufshcd_blk_pm_runtime_init from ufshcd_scsi_add_wlus, And call here ufshcd_blk_pm_runtime_init() ?

Thanks,
Avri

Quoted 6 lines

drivers/scsi/ufs/ufshcd.c +1 -0
+
        /*
         * Do not print messages during runtime PM to avoid never-ending cycles
* of messages written back to storage by user space causing runtime
--
2.18.0

Peter Wang

author

2022-04-26 12:18 UTC #2 lore raw

Quoted 48 lines · Avri Altman

Quoted 35 lines
From: Peter Wang <[email protected]>
Device WLun may enter RPM_SUSPENDED and the consumer is RPM_ACTIVE.
The error state is
Device Wlun RPM: status:2, usage_count:0
Consumer: 0:0:0:49476 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:49456 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:0 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:1 Link: rpm_active:1, RPM: status:2, usage_count:0
Consumer: 0:0:0:2 Link: rpm_active:1, RPM: status:0, usage_count:0
Because rpm enable before rpm delay set, scsi_autopm_put_device invoke by scsi_sysfs_add_sdev may cause consumer enter suspend immediately.
Thas will always set rpm_active to 1.
If driver_probe_device invoke pm_runtime_get_suppliers just befor previous scsi_autopm_put_device, the rpm_active will change to 1 after pm_runtime_put_suppliers.
Set this delay to avoid scsi_autopm_put_device enter suspend immediately.
Signed-off-by Peter Wang <[email protected]>
---
  drivers/scsi/ufs/ufshcd.c | 8 ++++++--
  1 file changed, 6 insertions(+), 2 deletions(-)
drivers/scsi/ufs/ufshcd.c +0 -0
index 3f9caafa91bf..1250792d16be 100644
@@ -5024,10 +5024,14 @@ static int ufshcd_slave_configure(struct
 scsi_device *sdev)
          * Block runtime-pm until all consumers are added.
          * Refer ufshcd_setup_links().
drivers/scsi/ufs/ufshcd.c static int ufshcd_slave_configure(struct · line 5034
Quoted 10 lines
drivers/scsi/ufs/ufshcd.c +5 -2
          */
-       if (is_device_wlun(sdev))
+       if (is_device_wlun(sdev)) {
                 pm_runtime_get_noresume(&sdev->sdev_gendev);
-       else if (ufshcd_is_rpm_autosuspend_allowed(hba))
+       } else if (ufshcd_is_rpm_autosuspend_allowed(hba)) {
                 sdev->rpm_autosuspend = 1;
+               pm_runtime_set_autosuspend_delay(&sdev->sdev_gendev,
+                       RPM_AUTOSUSPEND_DELAY_MS);
+       }
Maybe remove ufshcd_blk_pm_runtime_init from ufshcd_scsi_add_wlus, And call here ufshcd_blk_pm_runtime_init() ?

Quoted 2 lines

Thanks,
Avri

Hi Arvi,

Thanks review, but I need discard this patch because it is not correct.

Sorry for inconvenient.

Thanks

Peter

Quoted 7 lines

Quoted 7 lines
drivers/scsi/ufs/ufshcd.c +1 -0
+
         /*
          * Do not print messages during runtime PM to avoid never-ending cycles
* of messages written back to storage by user space causing runtime
--
2.18.0