| Message ID | 20200416203126.1210-1-beanhuo@micron.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | UFS Host Performance Booster (HPB v1.0) driver | expand |
On Thu, Apr 16, 2020 at 10:31:21PM +0200, huobean@gmail.com wrote: > From: Bean Huo <beanhuo@micron.com> > > Hi, > I disclose my development/changes on UFS HPB (UFS Host Performance Booster) to > the community, as this would enable more UFS developers to test and start an > iterative review and update process. > > The HPB is defined in Jedec Standard Universal Flash (UFS) Host Performance > Booster (HPB) Extension Version 1.0, which is designed to improve read > performance by utilizing the host side memory. Based on our testing, the HPB > can increase the random read performance by up to about 46% in the random read. > > The original HPB driver is from [1]. Based on it, I did optimizations, > simplifications, fixed reliability issues, implemented HPB host control mode > and make it much more readable. which's pushed to here [2] as V1. > > To avoid touching the traditional SCSI core, the HPB driver in this series HPB > patch chooses to develop under SCSI sub-system layer, and sits the same layer > with UFSHCD. At the same time, to minimize changes to UFSHCD driver, the HPB > driver submits its HPB READ BUFFER and HPB WRITE BUFFER requests to the scsi > device->request_queueu to execute, rather than that directly go through > raw UPIU request path. This feature is completley broken, and rather dangerous due to feeding "physical" addresses looked up by the host in. I do not think we should support something that broken in Linux. Independent of that using two requests in the I/O path is not going to fly either. The whole thing seems like an exercise in benchmarketing.
Hi, Christoph Thanks for your feedback. > > To avoid touching the traditional SCSI core, the HPB driver in this > > series HPB patch chooses to develop under SCSI sub-system layer, and > > sits the same layer with UFSHCD. At the same time, to minimize changes > > to UFSHCD driver, the HPB driver submits its HPB READ BUFFER and HPB > > WRITE BUFFER requests to the scsi > > device->request_queueu to execute, rather than that directly go > > device->through > > raw UPIU request path. > > This feature is completley broken, and rather dangerous due to feeding > "physical" addresses looked up by the host in. I do not think we should support > something that broken in Linux. > It Is not plain physical address, has been encrypted before loading from UFS to HPB memory, I think we don't worry about its safety. > Independent of that using two requests in the I/O path is not going to fly either. > The whole thing seems like an exercise in benchmarketing. I agree with you. This is my major concern. I have been thinking about HPB implementation in SCSI layer. That will let SCSI layer manage HPB by calling UFS helper interface. If you don't consider UFS HPB is an idiot design, I want to change in another version. Firstly, we really want to hear your suggestion. Thanks, //Bean
> > Hi, Christoph > Thanks for your feedback. > > > > To avoid touching the traditional SCSI core, the HPB driver in this > > > series HPB patch chooses to develop under SCSI sub-system layer, and > > > sits the same layer with UFSHCD. At the same time, to minimize changes > > > to UFSHCD driver, the HPB driver submits its HPB READ BUFFER and HPB > > > WRITE BUFFER requests to the scsi > > > device->request_queueu to execute, rather than that directly go > > > device->through > > > raw UPIU request path. > > > > This feature is completley broken, and rather dangerous due to feeding > > "physical" addresses looked up by the host in. I do not think we should > support > > something that broken in Linux. > > > > It Is not plain physical address, has been encrypted before loading from UFS > to > HPB memory, I think we don't worry about its safety. > > > Independent of that using two requests in the I/O path is not going to fly > either. > > The whole thing seems like an exercise in benchmarketing. > > I agree with you. This is my major concern. I have been thinking about HPB > implementation in SCSI layer. > That will let SCSI layer manage HPB by calling UFS helper interface. > If you don't consider UFS HPB is an idiot design, I want to change in another > version. Firstly, we really > want to hear your suggestion. > Thanks, > > //Bean If indeed this will move forward, please publish your patches as a RFC, To allow competing approaches to be published as well. Thanks, Avri
From: Bean Huo <beanhuo@micron.com> Hi, I disclose my development/changes on UFS HPB (UFS Host Performance Booster) to the community, as this would enable more UFS developers to test and start an iterative review and update process. The HPB is defined in Jedec Standard Universal Flash (UFS) Host Performance Booster (HPB) Extension Version 1.0, which is designed to improve read performance by utilizing the host side memory. Based on our testing, the HPB can increase the random read performance by up to about 46% in the random read. The original HPB driver is from [1]. Based on it, I did optimizations, simplifications, fixed reliability issues, implemented HPB host control mode and make it much more readable. which's pushed to here [2] as V1. To avoid touching the traditional SCSI core, the HPB driver in this series HPB patch chooses to develop under SCSI sub-system layer, and sits the same layer with UFSHCD. At the same time, to minimize changes to UFSHCD driver, the HPB driver submits its HPB READ BUFFER and HPB WRITE BUFFER requests to the scsi device->request_queueu to execute, rather than that directly go through raw UPIU request path. v1--v2: 1. Rebased the patch on the [3] branch 5.8/scsi-queue 1. Optimized and simplified several functions 2. Add parameter read_threshold in HPB sysfs, by which the user can change read_threshold for the HPB host control mode 3. Add HPB memory limitation, let the user adjust its size according to the system memory capacity [1] https://github.com/OpenMPDK/HPBDriver [2] https://www.spinics.net/lists/kernel/msg3449471.html [3] https://git.kernel.org/pub/scm/linux/kernel/git/mkp/scsi.git Bean Huo (5): scsi; ufs: add device descriptor for Host Performance Booster scsi: ufs: make ufshcd_read_unit_desc_param() non-static func scsi: ufs: add ufs_features parameter in structure ufs_dev_info scsi: ufs: add unit and geometry parameters for HPB scsi: ufs: UFS Host Performance Booster(HPB) driver drivers/scsi/ufs/Kconfig | 62 + drivers/scsi/ufs/Makefile | 1 + drivers/scsi/ufs/ufs.h | 15 + drivers/scsi/ufs/ufshcd.c | 66 +- drivers/scsi/ufs/ufshcd.h | 15 +- drivers/scsi/ufs/ufshpb.c | 3279 +++++++++++++++++++++++++++++++++++++ drivers/scsi/ufs/ufshpb.h | 450 +++++ 7 files changed, 3881 insertions(+), 7 deletions(-) create mode 100644 drivers/scsi/ufs/ufshpb.c create mode 100644 drivers/scsi/ufs/ufshpb.h