RE: [PATCH V5 00/13] mmc: Add Command Queue support

Bough Chen
2017-08-17T07:45:18Z

> -----Original Message-----
> From: linux-mmc-owner@vger.kernel.org [mailto:linux-mmc-
> owner@vger.kernel.org] On Behalf Of Adrian Hunter
> Sent: Thursday, August 10, 2017 8:08 PM
> To: Ulf Hansson <ulf.hansson@linaro.org>
> Cc: linux-mmc <linux-mmc@vger.kernel.org>; Bough Chen
> <haibo.chen@nxp.com>; Alex Lemberg <alex.lemberg@sandisk.com>;
> Mateusz Nowak <mateusz.nowak@intel.com>; Yuliy Izrailov
> <Yuliy.Izrailov@sandisk.com>; Jaehoon Chung <jh80.chung@samsung.com>;
> Dong Aisheng <dongas86@gmail.com>; Das Asutosh
> <asutoshd@codeaurora.org>; Zhangfei Gao <zhangfei.gao@gmail.com>;
> Sahitya Tummala <stummala@codeaurora.org>; Harjani Ritesh
> <riteshh@codeaurora.org>; Venu Byravarasu <vbyravarasu@nvidia.com>;
> Linus Walleij <linus.walleij@linaro.org>; Shawn Lin <shawn.lin@rock-chips.com>
> Subject: [PATCH V5 00/13] mmc: Add Command Queue support
>
> Hi
>
> Here is V5 of the hardware command queue patches without the software
> command queue patches.
>
> HW CMDQ offers 25% - 50% better random multi-threaded I/O. I see a slight 2%
> drop in sequential read speed but no change to sequential write.
>
>
Hi Adrian,

I test the performance on the i.MX8. Here in my side, I use 'dd' to test the
sequential read/write speed, see a slight 3% drop for both read and write.

---------------------------------------------
| | read (KB/s)| write (KB/s) |
---------------------------------------------
|CMDQ in HS400ES| 257 | 94.5 |
---------------------------------------------
| HS400ES | 265 | 96.6 |
---------------------------------------------

For random multi-threaded I/O, I use 'fio' to test, the test command:
fio -filename=/mnt/test -direct=1 -iodepth 1 -thread -rw=randread - ioengine=psync -bs=4k -size=2G -numjobs=10 -runtime=60 -group_reporting - name=mytest

I test 5 times, and get the average value.
For CMDQ in HS400ES
----------------------------------------------------
| block size | 4KB | 8KB | 16KB |
----------------------------------------------------
| random read | 26340KB/s | 51844KB/s | 85738KB/s |
----------------------------------------------------
| random write | 12691KB/s | 15879KB/s | 17535KB/s |
----------------------------------------------------

HS400ES without CMDQ
----------------------------------------------------
| block size | 4KB | 8KB | 16KB |
----------------------------------------------------
| random read | 18585KB/s | 35041KB/s | 63880KB/s |
----------------------------------------------------
| random write | 16465KB/s | 19210KB/s | 22672KB/s |
----------------------------------------------------

For random write from the test, I find every test value differ greatly no matter enable CMDQ or not.

>From the test, I see CMDQ random read speed increase 34%~48%, but for random write, the speed
drop 17.4% ~ 33%.

When you send software cmdq V5 patch, you give some explanation for the random write. But the
average random write speed also drops a lot, I think it is now a good news, which need attention!

Maybe Shawn Lin can double test this random write performance.

Best Regards
Haibo Chen

> Changes since V4:
> mmc: core: Add mmc_retune_hold_now()
> Add explanation to commit message.
> mmc: host: Add CQE interface
> Add comments to callback declarations.
> mmc: core: Turn off CQE before sending commands
> Add explanation to commit message.
> mmc: core: Add support for handling CQE requests
> Add comments as requested by Ulf.
> mmc: core: Remove unused MMC_CAP2_PACKED_CMD
> New patch.
> mmc: mmc: Enable Command Queuing
> Adjust for removal of MMC_CAP2_PACKED_CMD.
> Add a comment about Packed Commands.
> mmc: mmc: Enable CQE's
> Remove un-necessary check for MMC_CAP2_CQE
> mmc: block: Use local variables in mmc_blk_data_prep()
> New patch.
> mmc: block: Prepare CQE data
> Adjust due to "mmc: block: Use local variables in
> mmc_blk_data_prep()"
> Remove priority setting.
> Add explanation to commit message.
> mmc: cqhci: support for command queue enabled host
> Fix transfer descriptor setting in cqhci_set_tran_desc() for 32-bit DMA
>
> Changes since V3:
> Adjusted ...blk_end_request...() for new block status codes
> Fixed CQHCI transaction descriptor for "no DCMD" case
>
> Changes since V2:
> Dropped patches that have been applied.
> Re-based
> Added "mmc: sdhci-pci: Add CQHCI support for Intel GLK"
>
> Changes since V1:
>
> "Share mmc request array between partitions" is dependent
> on changes in "Introduce queue semantics", so added that
> and block fixes:
>
> Added "Fix is_waiting_last_req set incorrectly"
> Added "Fix cmd error reset failure path"
> Added "Use local var for mqrq_cur"
> Added "Introduce queue semantics"
>
> Changes since RFC:
>
> Re-based on next.
> Added comment about command queue priority.
> Added some acks and reviews.
>
>
> Adrian Hunter (12):
> mmc: core: Add mmc_retune_hold_now()
> mmc: core: Add members to mmc_request and mmc_data for CQE's
> mmc: host: Add CQE interface
> mmc: core: Turn off CQE before sending commands
> mmc: core: Add support for handling CQE requests
> mmc: core: Remove unused MMC_CAP2_PACKED_CMD
> mmc: mmc: Enable Command Queuing
> mmc: mmc: Enable CQE's
> mmc: block: Use local variables in mmc_blk_data_prep()
> mmc: block: Prepare CQE data
> mmc: block: Add CQE support
> mmc: sdhci-pci: Add CQHCI support for Intel GLK
>
> Venkat Gopalakrishnan (1):
> mmc: cqhci: support for command queue enabled host
>
> drivers/mmc/core/block.c | 238 +++++++-
> drivers/mmc/core/block.h | 7 +
> drivers/mmc/core/bus.c | 7 +
> drivers/mmc/core/core.c | 178 +++++-
> drivers/mmc/core/host.c | 6 +
> drivers/mmc/core/host.h | 1 +
> drivers/mmc/core/mmc.c | 42 +-
> drivers/mmc/core/queue.c | 273 ++++++++-
> drivers/mmc/core/queue.h | 42 +-
> drivers/mmc/host/Kconfig | 14 +
> drivers/mmc/host/Makefile | 1 +
> drivers/mmc/host/cqhci.c | 1154
> +++++++++++++++++++++++++++++++++++++
> drivers/mmc/host/cqhci.h | 240 ++++++++
> drivers/mmc/host/sdhci-pci-core.c | 153 ++++-
> include/linux/mmc/core.h | 18 +-
> include/linux/mmc/host.h | 63 +-
> include/trace/events/mmc.h | 36 +-
> 17 files changed, 2412 insertions(+), 61 deletions(-) create mode 100644
> drivers/mmc/host/cqhci.c create mode 100644 drivers/mmc/host/cqhci.h
>
>
> Regards
> Adrian
> --
> To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the
> body of a message to majordomo@vger.kernel.org More majordomo info at
> http://vger.kernel.org/majordomo-info.html