RE: [RFC PATCH 0/5]mmc: Soft Command queue implementation for eMMC5.1 device

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




> -----Original Message-----
> From: Ulf Hansson [mailto:ulf.hansson@xxxxxxxxxx]
> Sent: Friday, December 19, 2014 5:02 PM
> To: Dong, Chuanxiao
> Cc: linux-mmc
> Subject: Re: [RFC PATCH 0/5]mmc: Soft Command queue implementation for
> eMMC5.1 device
> 
> On 19 December 2014 at 09:04, Chuanxiao Dong <chuanxiao.dong@xxxxxxxxx>
> wrote:
> > Hello,
> >
> > Seems community already have some implementation for the eMMC5.1
> > device command queue feature, but that require the eMMC host
> > controller to support CMDQ. In my platform, I don't have this kind of
> > eMMC host controller but I have a Samsung eMMC5.1 device which can
> support the Command queue.
> >
> > With this limitation, I have to let eMMC host controller to manually
> > send the CMD44/45/13/46/47. So in this way, more commands are needed
> > for an I/O request, more interrupts/schedule are needed in driver.
> >
> > Even this way have some more software overhead, but it can still use
> > the eMMC5.1 device Command queue feature. After test with the iozone
> command:
> > "iozone -zec -t 4 -i0 -i2 -F iozonefile1 iozonefile2 iozonefile3
> > iozonefile4 -+n -I -r 4k -s 500m -O -R -+r -+D" to test random
> > performance, I saw a performance improvment for random read on my
> eMMC5.1 device:
> >
> >                 Random read
> > SW CMDQ:        5544.6
> > Normal Read:    3993.05
> 
> Thanks for the patchset Chuanxiao! I will spend some time reviewing this in
> more detail as soon as I can.
> 
> One important point though, before I start reviewing. I would like the "Normal
> read" to be performed for a host driver supporting the asynchronous mmc
> request feature. Currently sdhci don't support this, but there is patch
> suggesting to add this which you might want to use/review.
> https://www.marc.info/?l=linux-mmc&m=141811588607432&w=2
> 
> Kind regards
> Uffe
Thanks Uffe for the sharing. I will look into this patch and try on my platform.

Thanks
Chuanxiao

> 
> >
> > So I want to send this serial patches as RFC patch for reviewing
> >
> >
> > Chuanxiao Dong (5):
> >   mmc: replace sbc to precmd and add postcmd
> >   mmc: host: add runtime PM for host class dev
> >   mmc: queue: change mqrq_cur and mqrq_pre to mq qdepth
> >   mmc: core: add support for CMDQ feature in MMC Core stack
> >   mmc: sdhci: add SW CMDQ support for CHT SDHCI host
> >
> >  drivers/mmc/card/block.c      |  538
> ++++++++++++++++++++++++++++++++++++++---
> >  drivers/mmc/card/queue.c      |  213 ++++++++--------
> >  drivers/mmc/card/queue.h      |   14 +-
> >  drivers/mmc/core/core.c       |   78 +++++-
> >  drivers/mmc/core/host.c       |   14 ++
> >  drivers/mmc/core/mmc.c        |   43 +++-
> >  drivers/mmc/host/dw_mmc.c     |    8 +-
> >  drivers/mmc/host/mmci.c       |   14 +-
> >  drivers/mmc/host/omap_hsmmc.c |   18 +-
> >  drivers/mmc/host/sdhci-acpi.c |    1 -
> >  drivers/mmc/host/sdhci-pci.c  |    1 -
> >  drivers/mmc/host/sdhci.c      |  137 +++++++++--
> >  include/linux/mmc/card.h      |    3 +
> >  include/linux/mmc/core.h      |    5 +-
> >  include/linux/mmc/host.h      |    5 +
> >  include/linux/mmc/mmc.h       |   21 ++
> >  include/linux/mmc/pm.h        |    1 +
> >  include/linux/mmc/sdhci.h     |    1 +
> >  18 files changed, 909 insertions(+), 206 deletions(-)
> >
> > --
> > 1.7.10.4
> > --
> > To unsubscribe from this list: send the line "unsubscribe linux-mmc"
> > in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo
> > info at  http://vger.kernel.org/majordomo-info.html
��.n��������+%������w��{.n�����{��i��)��jg��������ݢj����G�������j:+v���w�m������w�������h�����٥





[Index of Archives]     [Linux USB Devel]     [Linux Media]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux