[v6,00/10] Add Host control mode to HPB

Message

Avri Altman March 22, 2021, 8:10 a.m. UTC

v5 -> v6:
 - attend CanG's comments
 - rebase on Daejun's v31

v4 -> v5:
 - attend Daejun's comments
 - Control the number of inflight map requests

v3 -> v4:
 - rebase on Daejun's v25

v2 -> v3:
 - Attend Greg's and Can's comments
 - rebase on Daejun's v21

v1 -> v2:
 - attend Greg's and Daejun's comments
 - add patch 9 making host mode parameters configurable
 - rebase on Daejun's v19


The HPB spec defines 2 control modes - device control mode and host
control mode. In oppose to device control mode, in which the host obey
to whatever recommendation received from the device - In host control
mode, the host uses its own algorithms to decide which regions should
be activated or inactivated.

We kept the host managed heuristic simple and concise.

Aside from adding a by-spec functionality, host control mode entails
some further potential benefits: makes the hpb logic transparent and
readable, while allow tuning / scaling its various parameters, and
utilize system-wide info to optimize HPB potential.

This series is based on Samsung's V31 device-control HPB2.0 driver, see
msg-id: CGME20210322064159epcms2p6a4c7deed5f81eaa4f2a8340aaedb446c@epcms2p6
in lore.kernel.org.

This version was tested on Galaxy S20, and Xiaomi Mi10 pro.
Your meticulous review and testing is mostly welcome and appreciated.

Thanks,
Avri

Avri Altman (10):
  scsi: ufshpb: Cache HPB Control mode on init
  scsi: ufshpb: Add host control mode support to rsp_upiu
  scsi: ufshpb: Add region's reads counter
  scsi: ufshpb: Make eviction depends on region's reads
  scsi: ufshpb: Region inactivation in host mode
  scsi: ufshpb: Add hpb dev reset response
  scsi: ufshpb: Add "Cold" regions timer
  scsi: ufshpb: Limit the number of inflight map requests
  scsi: ufshpb: Add support for host control mode
  scsi: ufshpb: Make host mode parameters configurable

 Documentation/ABI/testing/sysfs-driver-ufs |  84 +++-
 drivers/scsi/ufs/ufshcd.h                  |   2 +
 drivers/scsi/ufs/ufshpb.c                  | 547 ++++++++++++++++++++-
 drivers/scsi/ufs/ufshpb.h                  |  39 ++
 4 files changed, 635 insertions(+), 37 deletions(-)