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[v13,0/2] Enable power management for ufs wlun

Message ID cover.1616633712.git.asutoshd@codeaurora.org
Headers show
Series Enable power management for ufs wlun | expand

Message

Asutosh Das (asd) March 25, 2021, 1:39 a.m. UTC
This patch attempts to fix a deadlock in ufs while sending SSU.
Recently, blk_queue_enter() added a check to not process requests if the
queue is suspended. That leads to a resume of the associated device which
is suspended. In ufs, that device is ufs device wlun and it's parent is
ufs_hba. This resume tries to resume ufs device wlun which in turn tries
to resume ufs_hba, which is already in the process of suspending, thus
causing a deadlock.

This patch takes care of:
* Suspending the ufs device lun only after all other luns are suspended
* Sending SSU during ufs device wlun suspend
* Clearing uac for rpmb and ufs device wlun
* Not sending commands to the device during host suspend

v12 -> v13:
- Addressed Adrian's comments
  * Paired pm_runtime_get_noresume() with pm_runtime_put()
  * no rpm_autosuspend for ufs device wlun
  * Moved runtime-pm init functionality to ufshcd_wl_probe()
- Addressed Bart's comments
  * Expanded abbrevs in commit message

v11 -> v12:
- Addressed Adrian's comments
  * Fixed ahit for Mediatek driver
  * Fixed error handling in ufshcd_core_init()
  * Tested this patch and the issue is still seen.

v10 -> v11:
- Fixed supplier suspending before consumer race
- Addressed Adrian's comments
  * Added proper resume/suspend cb to ufshcd_auto_hibern8_update()
  * Cosmetic changes to ufshcd-pci.c
  * Cleaned up ufshcd_system_suspend()
  * Added ufshcd_debugfs_eh_exit to ufshcd_core_init()

v9 -> v10:
- Addressed Adrian's comments
  * Moved suspend/resume vops to __ufshcd_wl_[suspend/resume]()
  * Added correct resume in ufs_bsg

v8 -> v9:
- Addressed Adrian's comments
  * Moved link transition to __ufshcd_wl_[suspend/resume]()
  * Fixed the other minor comments

v7 -> v8:
- Addressed Adrian's comments
  * Removed separate autosuspend delay for ufs-device lun
  * Fixed the ee handler getting scheduled during pm
  * Always runtime resume in suspend_prepare()
  * Added CONFIG_PM_SLEEP where needed
  
v6 -> v7:
  * Resume the ufs device before shutting it down

v5 -> v6:
- Addressed Adrian's comments
  * Added complete() cb
  * Added suspend_prepare() and complete() to all drivers
  * Moved suspend_prepare() and complete() to ufshcd
  * .poweroff() uses ufhcd_wl_poweroff()
  * Removed several forward declarations
  * Moved scsi_register_driver() to ufshcd_core_init()

v4 -> v5:
- Addressed Adrian's comments
  * Used the rpmb driver contributed by Adrian
  * Runtime-resume the ufs device during suspend to honor spm-lvl
  * Unregister the scsi_driver in ufshcd_remove()
  * Currently shutdown() puts the ufs device to power-down mode
    so, just removed ufshcd_pci_poweroff()
  * Quiesce the scsi device during shutdown instead of remove

v3 RFC -> v4:
- Addressed Bart's comments
  * Except that I didn't get any checkpatch failures
- Addressed Avri's comments
- Addressed Adrian's comments
  * Added a check for deepsleep power mode
  * Removed a couple of forward declarations
  * Didn't separate the scsi drivers because in rpmb case it just sends uac
    in resume and it seemed pretty neat to me.
- Added sysfs changes to resume the devices before accessing

Asutosh Das (2):
  scsi: ufs: Enable power management for wlun
  ufs: sysfs: Resume the proper scsi device

 drivers/scsi/ufs/cdns-pltfrm.c     |   2 +
 drivers/scsi/ufs/tc-dwc-g210-pci.c |   2 +
 drivers/scsi/ufs/ufs-debugfs.c     |   2 +-
 drivers/scsi/ufs/ufs-debugfs.h     |   2 +-
 drivers/scsi/ufs/ufs-exynos.c      |   2 +
 drivers/scsi/ufs/ufs-hisi.c        |   2 +
 drivers/scsi/ufs/ufs-mediatek.c    |  12 +-
 drivers/scsi/ufs/ufs-qcom.c        |   2 +
 drivers/scsi/ufs/ufs-sysfs.c       |  30 +-
 drivers/scsi/ufs/ufs_bsg.c         |   6 +-
 drivers/scsi/ufs/ufshcd-pci.c      |  36 +--
 drivers/scsi/ufs/ufshcd.c          | 627 ++++++++++++++++++++++++++-----------
 drivers/scsi/ufs/ufshcd.h          |   6 +
 include/trace/events/ufs.h         |  20 ++
 14 files changed, 513 insertions(+), 238 deletions(-)

Comments

Asutosh Das (asd) March 29, 2021, 10:48 p.m. UTC | #1
On 3/24/2021 6:39 PM, Asutosh Das wrote:
> This patch attempts to fix a deadlock in ufs while sending SSU.
> Recently, blk_queue_enter() added a check to not process requests if the
> queue is suspended. That leads to a resume of the associated device which
> is suspended. In ufs, that device is ufs device wlun and it's parent is
> ufs_hba. This resume tries to resume ufs device wlun which in turn tries
> to resume ufs_hba, which is already in the process of suspending, thus
> causing a deadlock.
> 
> This patch takes care of:
> * Suspending the ufs device lun only after all other luns are suspended
> * Sending SSU during ufs device wlun suspend
> * Clearing uac for rpmb and ufs device wlun
> * Not sending commands to the device during host suspend
> 
> v12 -> v13:
> - Addressed Adrian's comments
>    * Paired pm_runtime_get_noresume() with pm_runtime_put()
>    * no rpm_autosuspend for ufs device wlun
>    * Moved runtime-pm init functionality to ufshcd_wl_probe()
> - Addressed Bart's comments
>    * Expanded abbrevs in commit message
> 

Hi Adrian
I did a limited testing on your fix in the pm framework along with this 
v13 patchset. I couldn't reproduce the issue.

I'd appreciate if you can please take a look at the v13 changes.
If all looks good in that, I'd do an extensive testing.

Thanks,
-asd

> v11 -> v12:
> - Addressed Adrian's comments
>    * Fixed ahit for Mediatek driver
>    * Fixed error handling in ufshcd_core_init()
>    * Tested this patch and the issue is still seen.
> 
> v10 -> v11:
> - Fixed supplier suspending before consumer race
> - Addressed Adrian's comments
>    * Added proper resume/suspend cb to ufshcd_auto_hibern8_update()
>    * Cosmetic changes to ufshcd-pci.c
>    * Cleaned up ufshcd_system_suspend()
>    * Added ufshcd_debugfs_eh_exit to ufshcd_core_init()
> 
> v9 -> v10:
> - Addressed Adrian's comments
>    * Moved suspend/resume vops to __ufshcd_wl_[suspend/resume]()
>    * Added correct resume in ufs_bsg
> 
> v8 -> v9:
> - Addressed Adrian's comments
>    * Moved link transition to __ufshcd_wl_[suspend/resume]()
>    * Fixed the other minor comments
> 
> v7 -> v8:
> - Addressed Adrian's comments
>    * Removed separate autosuspend delay for ufs-device lun
>    * Fixed the ee handler getting scheduled during pm
>    * Always runtime resume in suspend_prepare()
>    * Added CONFIG_PM_SLEEP where needed
>    
> v6 -> v7:
>    * Resume the ufs device before shutting it down
> 
> v5 -> v6:
> - Addressed Adrian's comments
>    * Added complete() cb
>    * Added suspend_prepare() and complete() to all drivers
>    * Moved suspend_prepare() and complete() to ufshcd
>    * .poweroff() uses ufhcd_wl_poweroff()
>    * Removed several forward declarations
>    * Moved scsi_register_driver() to ufshcd_core_init()
> 
> v4 -> v5:
> - Addressed Adrian's comments
>    * Used the rpmb driver contributed by Adrian
>    * Runtime-resume the ufs device during suspend to honor spm-lvl
>    * Unregister the scsi_driver in ufshcd_remove()
>    * Currently shutdown() puts the ufs device to power-down mode
>      so, just removed ufshcd_pci_poweroff()
>    * Quiesce the scsi device during shutdown instead of remove
> 
> v3 RFC -> v4:
> - Addressed Bart's comments
>    * Except that I didn't get any checkpatch failures
> - Addressed Avri's comments
> - Addressed Adrian's comments
>    * Added a check for deepsleep power mode
>    * Removed a couple of forward declarations
>    * Didn't separate the scsi drivers because in rpmb case it just sends uac
>      in resume and it seemed pretty neat to me.
> - Added sysfs changes to resume the devices before accessing
> 
> Asutosh Das (2):
>    scsi: ufs: Enable power management for wlun
>    ufs: sysfs: Resume the proper scsi device
> 
>   drivers/scsi/ufs/cdns-pltfrm.c     |   2 +
>   drivers/scsi/ufs/tc-dwc-g210-pci.c |   2 +
>   drivers/scsi/ufs/ufs-debugfs.c     |   2 +-
>   drivers/scsi/ufs/ufs-debugfs.h     |   2 +-
>   drivers/scsi/ufs/ufs-exynos.c      |   2 +
>   drivers/scsi/ufs/ufs-hisi.c        |   2 +
>   drivers/scsi/ufs/ufs-mediatek.c    |  12 +-
>   drivers/scsi/ufs/ufs-qcom.c        |   2 +
>   drivers/scsi/ufs/ufs-sysfs.c       |  30 +-
>   drivers/scsi/ufs/ufs_bsg.c         |   6 +-
>   drivers/scsi/ufs/ufshcd-pci.c      |  36 +--
>   drivers/scsi/ufs/ufshcd.c          | 627 ++++++++++++++++++++++++++-----------
>   drivers/scsi/ufs/ufshcd.h          |   6 +
>   include/trace/events/ufs.h         |  20 ++
>   14 files changed, 513 insertions(+), 238 deletions(-)
>
Adrian Hunter March 30, 2021, 10:07 a.m. UTC | #2
On 30/03/21 1:48 am, Asutosh Das (asd) wrote:
> On 3/24/2021 6:39 PM, Asutosh Das wrote:

>> This patch attempts to fix a deadlock in ufs while sending SSU.

>> Recently, blk_queue_enter() added a check to not process requests if the

>> queue is suspended. That leads to a resume of the associated device which

>> is suspended. In ufs, that device is ufs device wlun and it's parent is

>> ufs_hba. This resume tries to resume ufs device wlun which in turn tries

>> to resume ufs_hba, which is already in the process of suspending, thus

>> causing a deadlock.

>>

>> This patch takes care of:

>> * Suspending the ufs device lun only after all other luns are suspended

>> * Sending SSU during ufs device wlun suspend

>> * Clearing uac for rpmb and ufs device wlun

>> * Not sending commands to the device during host suspend

>>

>> v12 -> v13:

>> - Addressed Adrian's comments

>>    * Paired pm_runtime_get_noresume() with pm_runtime_put()

>>    * no rpm_autosuspend for ufs device wlun

>>    * Moved runtime-pm init functionality to ufshcd_wl_probe()

>> - Addressed Bart's comments

>>    * Expanded abbrevs in commit message

>>

> 

> Hi Adrian

> I did a limited testing on your fix in the pm framework along with this v13 patchset. I couldn't reproduce the issue.

> 

> I'd appreciate if you can please take a look at the v13 changes.

> If all looks good in that, I'd do an extensive testing.


I made a couple of comments on the patch, but nothing major.