From patchwork Fri Jun 5 01:16:04 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Daejun Park X-Patchwork-Id: 11588825 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5CD3092A for ; Fri, 5 Jun 2020 01:20:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4354520872 for ; Fri, 5 Jun 2020 01:20:06 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="b8wLoTuT" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726142AbgFEBUF (ORCPT ); Thu, 4 Jun 2020 21:20:05 -0400 Received: from mailout1.samsung.com ([203.254.224.24]:58043 "EHLO mailout1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725863AbgFEBUE (ORCPT ); Thu, 4 Jun 2020 21:20:04 -0400 Received: from epcas1p3.samsung.com (unknown [182.195.41.47]) by mailout1.samsung.com (KnoxPortal) with ESMTP id 20200605012002epoutp012bbef540448f8228e478b1c129e910e6~VgRxZb6PX2266422664epoutp01c for ; Fri, 5 Jun 2020 01:20:02 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.samsung.com 20200605012002epoutp012bbef540448f8228e478b1c129e910e6~VgRxZb6PX2266422664epoutp01c DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1591320002; bh=jutr7CvxY0Z0Ep4LAxqYwasBfx4P75gJk8iYttlHMAc=; h=Subject:Reply-To:From:To:CC:Date:References:From; b=b8wLoTuTr/rqiEjfa1zD5pzk1ZqT+GZ9lzTMjyhrlhxRE4zwy+D9A3Pml8/Q4V2j4 DWGdcR1gsn13y+LQ6LaIAngXlW0925lYZC5TjLLzxjarA7Mk4kfkUi6uJU3EX0EZJI 3PZb/YvpaC6G7BpxdIdgUMIKv2jrv6Vg1PBs0Axw= Received: from epcpadp1 (unknown [182.195.40.11]) by epcas1p3.samsung.com (KnoxPortal) with ESMTP id 20200605012001epcas1p38044c63946e19a5bd85da1b0b7d084b7~VgRw1tlm60328903289epcas1p3A; Fri, 5 Jun 2020 01:20:01 +0000 (GMT) Mime-Version: 1.0 Subject: [RFC PATCH 0/5] scsi: ufs: Add Host Performance Booster Support Reply-To: daejun7.park@samsung.com From: Daejun Park To: ALIM AKHTAR , "avri.altman@wdc.com" , "jejb@linux.ibm.com" , "martin.petersen@oracle.com" , "asutoshd@codeaurora.org" , "beanhuo@micron.com" , "stanley.chu@mediatek.com" , "cang@codeaurora.org" , "bvanassche@acm.org" , "tomas.winkler@intel.com" , Daejun Park CC: "linux-scsi@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Sang-yoon Oh , Sung-Jun Park , yongmyung lee , Jinyoung CHOI , Adel Choi , BoRam Shin X-Priority: 3 X-Content-Kind-Code: NORMAL X-CPGS-Detection: blocking_info_exchange X-Drm-Type: N,general X-Msg-Generator: Mail X-Msg-Type: PERSONAL X-Reply-Demand: N Message-ID: <231786897.01591320001492.JavaMail.epsvc@epcpadp1> Date: Fri, 05 Jun 2020 10:16:04 +0900 X-CMS-MailID: 20200605011604epcms2p8bec8ef6682583d7248dc7d9dc1bfc882 X-Sendblock-Type: AUTO_CONFIDENTIAL X-CPGSPASS: Y X-CPGSPASS: Y X-Hop-Count: 3 X-CMS-RootMailID: 20200605011604epcms2p8bec8ef6682583d7248dc7d9dc1bfc882 References: Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org NAND flash memory-based storage devices use Flash Translation Layer (FTL) to translate logical addresses of I/O requests to corresponding flash memory addresses. Mobile storage devices typically have RAM with constrained size, thus lack in memory to keep the whole mapping table. Therefore, mapping tables are partially retrieved from NAND flash on demand, causing random-read performance degradation. To improve random read performance, we propose HPB (Host Performance Booster) which uses host system memory as a cache for the FTL mapping table. By using HPB, FTL data can be read from host memory faster than from NAND flash memory. The current version only supports the DCM (device control mode). This patch consists of 4 parts to support HPB feature. 1) UFS-feature layer 2) HPB probe and initialization process 3) READ -> HPB READ using cached map information 4) L2P (logical to physical) map management The UFS-feature is an additional layer to avoid the structure in which the UFS-core driver and the UFS-feature are entangled with each other in a single module. By adding the layer, UFS-features composed of various combinations can be supported. Also, even if a new feature is added, modification of the UFS-core driver can be minimized. In the HPB probe and init process, the device information of the UFS is queried. After checking supported features, the data structure for the HPB is initialized according to the device information. A read I/O in the active sub-region where the map is cached is changed to HPB READ by the HPB module. The HPB module manages the L2P map using information received from the device. For active sub-region, the HPB module caches through ufshpb_map request. For the in-active region, the HPB module discards the L2P map. When a write I/O occurs in an active sub-region area, associated dirty bitmap checked as dirty for preventing stale read. HPB is shown to have a performance improvement of 58 - 67% for random read workload. [1] This series patches are based on the "5.8/scsi-queue" branch. [1]: https://www.usenix.org/conference/hotstorage17/program/presentation/jeong Daejun park (5): scsi: ufs: Add UFS feature related parameter scsi: ufs: Add UFS feature layer scsi: ufs: Introduce HPB module scsi: ufs: L2P map management for HPB read scsi: ufs: Prepare HPB read for cached sub-region drivers/scsi/ufs/Kconfig | 8 + drivers/scsi/ufs/Makefile | 3 +- drivers/scsi/ufs/ufs.h | 11 + drivers/scsi/ufs/ufsfeature.c | 178 ++++ drivers/scsi/ufs/ufsfeature.h | 95 ++ drivers/scsi/ufs/ufshcd.c | 19 + drivers/scsi/ufs/ufshcd.h | 3 + drivers/scsi/ufs/ufshpb.c | 2029 +++++++++++++++++++++++++++++++++++++++++ drivers/scsi/ufs/ufshpb.h | 257 ++++++ 9 files changed, 2602 insertions(+), 1 deletion(-) created mode 100644 drivers/scsi/ufs/ufsfeature.c created mode 100644 drivers/scsi/ufs/ufsfeature.h created mode 100644 drivers/scsi/ufs/ufshpb.c created mode 100644 drivers/scsi/ufs/ufshpb.h