Hi Haibo. On Mon, Jun 8, 2020 at 2:35 PM BOUGH CHEN <haibo.chen@xxxxxxx> wrote: > > > -----Original Message----- > > From: linux-mmc-owner@xxxxxxxxxxxxxxx > > [mailto:linux-mmc-owner@xxxxxxxxxxxxxxx] On Behalf Of Baolin Wang > > Sent: 2020年2月19日 9:35 > > To: Ulf Hansson <ulf.hansson@xxxxxxxxxx> > > Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>; Asutosh Das > > <asutoshd@xxxxxxxxxxxxxx>; Orson Zhai <orsonzhai@xxxxxxxxx>; Chunyan > > Zhang <zhang.lyra@xxxxxxxxx>; Arnd Bergmann <arnd@xxxxxxxx>; Linus > > Walleij <linus.walleij@xxxxxxxxxx>; Baolin Wang <baolin.wang@xxxxxxxxxx>; > > linux-mmc@xxxxxxxxxxxxxxx; Linux Kernel Mailing List > > <linux-kernel@xxxxxxxxxxxxxxx> > > Subject: Re: [PATCH v9 0/5] Add MMC software queue support > > > > On Wed, Feb 19, 2020 at 7:38 AM Ulf Hansson <ulf.hansson@xxxxxxxxxx> > > wrote: > > > > > > On Wed, 12 Feb 2020 at 05:14, Baolin Wang <baolin.wang7@xxxxxxxxx> > > wrote: > > > > > > > > Hi All, > > > > > > > > Now the MMC read/write stack will always wait for previous request > > > > is completed by mmc_blk_rw_wait(), before sending a new request to > > > > hardware, or queue a work to complete request, that will bring > > > > context switching overhead, especially for high I/O per second > > > > rates, to affect the IO performance. > > > > > > > > Thus this patch set will introduce the MMC software command queue > > > > support based on command queue engine's interfaces, and set the > > > > queue depth as 64 to allow more requests can be be prepared, merged > > > > and inserted into IO scheduler, but we only allow 2 requests in > > > > flight, that is enough to let the irq handler always trigger the > > > > next request without a context switch, as well as avoiding a long latency. > > > > > > > > Moreover we can expand the MMC software queue interface to support > > > > MMC packed request or packed command instead of adding new > > > > interfaces, according to previosus discussion. > > > > > > > > Below are some comparison data with fio tool. The fio command I used > > > > is like below with changing the '--rw' parameter and enabling the > > > > direct IO flag to measure the actual hardware transfer speed in 4K block > > size. > > > > > > > > ./fio --filename=/dev/mmcblk0p30 --direct=1 --iodepth=20 --rw=read > > > > --bs=4K --size=1G --group_reporting --numjobs=20 --name=test_read > > > > > > > > My eMMC card working at HS400 Enhanced strobe mode: > > > > [ 2.229856] mmc0: new HS400 Enhanced strobe MMC card at address > > 0001 > > > > [ 2.237566] mmcblk0: mmc0:0001 HBG4a2 29.1 GiB > > > > [ 2.242621] mmcblk0boot0: mmc0:0001 HBG4a2 partition 1 4.00 MiB > > > > [ 2.249110] mmcblk0boot1: mmc0:0001 HBG4a2 partition 2 4.00 MiB > > > > [ 2.255307] mmcblk0rpmb: mmc0:0001 HBG4a2 partition 3 4.00 MiB, > > chardev (248:0) > > > > > > > > 1. Without MMC software queue > > > > I tested 5 times for each case and output a average speed. > > > > > > > > 1) Sequential read: > > > > Speed: 59.4MiB/s, 63.4MiB/s, 57.5MiB/s, 57.2MiB/s, 60.8MiB/s Average > > > > speed: 59.66MiB/s > > > > > > > > 2) Random read: > > > > Speed: 26.9MiB/s, 26.9MiB/s, 27.1MiB/s, 27.1MiB/s, 27.2MiB/s Average > > > > speed: 27.04MiB/s > > > > > > > > 3) Sequential write: > > > > Speed: 71.6MiB/s, 72.5MiB/s, 72.2MiB/s, 64.6MiB/s, 67.5MiB/s Average > > > > speed: 69.68MiB/s > > > > > > > > 4) Random write: > > > > Speed: 36.3MiB/s, 35.4MiB/s, 38.6MiB/s, 34MiB/s, 35.5MiB/s Average > > > > speed: 35.96MiB/s > > > > > > > > 2. With MMC software queue > > > > I tested 5 times for each case and output a average speed. > > > > > > > > 1) Sequential read: > > > > Speed: 59.2MiB/s, 60.4MiB/s, 63.6MiB/s, 60.3MiB/s, 59.9MiB/s Average > > > > speed: 60.68MiB/s > > > > > > > > 2) Random read: > > > > Speed: 31.3MiB/s, 31.4MiB/s, 31.5MiB/s, 31.3MiB/s, 31.3MiB/s Average > > > > speed: 31.36MiB/s > > > > > > > > 3) Sequential write: > > > > Speed: 71MiB/s, 71.8MiB/s, 72.3MiB/s, 72.2MiB/s, 71MiB/s Average > > > > speed: 71.66MiB/s > > > > > > > > 4) Random write: > > > > Speed: 68.9MiB/s, 68.7MiB/s, 68.8MiB/s, 68.6MiB/s, 68.8MiB/s Average > > > > speed: 68.76MiB/s > > > > > > > > Form above data, we can see the MMC software queue can help to > > > > improve some performance obviously for random read and write, though > > > > no obvious improvement for sequential read and write. > > > > > > > > Any comments are welcome. Thanks a lot. > > > > > > Hi Baolin, > > I refer to your code, and add the software queue support on i.MX based on the Linux next-20200602, but unfortunately, I see an obvious performance drop when change to use software queue. > I test on our imx850-evk board, with eMMC soldered. > From the result listing below, only random write has a little performance improve, for others, seems performance drop a lot. > I noticed that, this software queue need no-removable card, any other limitation? For host? > From the code logic, software queue complete the request in irq handler, seems no other change, I do not figure out why this will trigger a performance drop on my platform. Any comment would be appreciate! Have you tested with below patches, which introduce an atomic_request host ops to submit next request in the irq hard handler context to reduce latency? https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=ed6330330276cba39058e8dbdb28ab8d013d926e https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a374a72baa817388a04825118b7c1ba13064c8c6 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=98a2642f91a47dcd1215d037c14e0e5de33a247d https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e872f1e22ea5f678ae42812949477387fda6725b https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=845c939ee22943786a6eb1d13d03c77b19fcc2c8 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6db96e5810e0a6a345b7d78549de7676ae5b2662 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=48ef8a2a1e5e6a2a189009e880e341ddb452971d https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=61ab64e2f54f4c607428667f83f411cb659843a3 > Without software queue, normal read/write method: > Sequential read: 56MB/s > Random read: 23.5MB/s > Sequential write: 43.7MB/s > Random write: 19MB/s > > With mmc software queue: > Sequential read: 33.5MB/s > Random read: 18.7 MB/s > Sequential write: 37.7MB/s > Random write: 19.8MB/s > > > Here, I also list my change code to support software queue > > diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig > index eb85237bf2d6..996b8cc5c381 100644 > --- a/drivers/mmc/host/Kconfig > +++ b/drivers/mmc/host/Kconfig > @@ -254,6 +254,7 @@ config MMC_SDHCI_ESDHC_IMX > depends on MMC_SDHCI_PLTFM > select MMC_SDHCI_IO_ACCESSORS > select MMC_CQHCI > + select MMC_HSQ > help > This selects the Freescale eSDHC/uSDHC controller support > found on i.MX25, i.MX35 i.MX5x and i.MX6x. > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c > index 1d7f84b23a22..6f163695b08d 100644 > --- a/drivers/mmc/host/sdhci-esdhc-imx.c > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c > @@ -29,6 +29,7 @@ > #include "sdhci-pltfm.h" > #include "sdhci-esdhc.h" > #include "cqhci.h" > +#include "mmc_hsq.h" > > #define ESDHC_SYS_CTRL_DTOCV_MASK 0x0f > #define ESDHC_CTRL_D3CD 0x08 > @@ -1220,6 +1221,15 @@ static u32 esdhc_cqhci_irq(struct sdhci_host *host, u32 intmask) > return 0; > } > > +static void esdhc_request_done(struct sdhci_host *host, struct mmc_request *mrq) > +{ > + /* Validate if the request was from software queue firstly. */ > + if (mmc_hsq_finalize_request(host->mmc, mrq)) > + return; > + > + mmc_request_done(host->mmc, mrq); > +} > + > static struct sdhci_ops sdhci_esdhc_ops = { > .read_l = esdhc_readl_le, > .read_w = esdhc_readw_le, > @@ -1237,6 +1247,7 @@ static struct sdhci_ops sdhci_esdhc_ops = { > .set_uhs_signaling = esdhc_set_uhs_signaling, > .reset = esdhc_reset, > .irq = esdhc_cqhci_irq, > + .request_done = esdhc_request_done, > }; > > static const struct sdhci_pltfm_data sdhci_esdhc_imx_pdata = { > @@ -1301,6 +1312,19 @@ static void sdhci_esdhc_imx_hwinit(struct sdhci_host *host) > writel(tmp, host->ioaddr + ESDHC_VEND_SPEC2); > > host->quirks &= ~SDHCI_QUIRK_NO_BUSY_IRQ; > + > + /* > + * On i.MX8MM, we are running Dual Linux OS, with 1st Linux using SD Card > + * as rootfs storage, 2nd Linux using eMMC as rootfs storage. We let the > + * the 1st linux configure power/clock for the 2nd Linux. > + * > + * When the 2nd Linux is booting into rootfs stage, we let the 1st Linux > + * to destroy the 2nd linux, then restart the 2nd linux, we met SDHCI dump. > + * After we clear the pending interrupt and halt CQCTL, issue gone. > + */ > + tmp = cqhci_readl(cq_host, CQHCI_IS); > + cqhci_writel(cq_host, tmp, CQHCI_IS); > + cqhci_writel(cq_host, CQHCI_HALT, CQHCI_CTL); > } > > if (imx_data->socdata->flags & ESDHC_FLAG_STD_TUNING) { > @@ -1351,9 +1375,6 @@ static void sdhci_esdhc_imx_hwinit(struct sdhci_host *host) > * After we clear the pending interrupt and halt CQCTL, issue gone. > */ > if (cq_host) { > - tmp = cqhci_readl(cq_host, CQHCI_IS); > - cqhci_writel(cq_host, tmp, CQHCI_IS); > - cqhci_writel(cq_host, CQHCI_HALT, CQHCI_CTL); > } > } > } > @@ -1555,6 +1576,7 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > struct sdhci_pltfm_host *pltfm_host; > struct sdhci_host *host; > struct cqhci_host *cq_host; > + struct mmc_hsq *hsq; > int err; > struct pltfm_imx_data *imx_data; > > @@ -1664,6 +1686,16 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > err = cqhci_init(cq_host, host->mmc, false); > if (err) > goto disable_ahb_clk; > + } else if (esdhc_is_usdhc(imx_data)) { > + hsq = devm_kzalloc(&pdev->dev, sizeof(*hsq), GFP_KERNEL); > + if (!hsq) { > + err = -ENOMEM; > + goto disable_ahb_clk; > + } > + > + err = mmc_hsq_init(hsq, host->mmc); > + if (err) > + goto disable_ahb_clk; > } > > if (of_id) > @@ -1673,6 +1705,11 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev) > if (err) > goto disable_ahb_clk; > > + if (!mmc_card_is_removable(host->mmc)) > + host->mmc_host_ops.request_atomic = sdhci_request_atomic; > + else > + host->always_defer_done = true; > + > sdhci_esdhc_imx_hwinit(host); > > err = sdhci_add_host(host); > @@ -1737,6 +1774,8 @@ static int sdhci_esdhc_suspend(struct device *dev) > ret = cqhci_suspend(host->mmc); > if (ret) > return ret; > + } else if (esdhc_is_usdhc(imx_data)) { > + mmc_hsq_suspend(host->mmc); > } > > if ((imx_data->socdata->flags & ESDHC_FLAG_STATE_LOST_IN_LPMODE) && > @@ -1764,6 +1803,8 @@ static int sdhci_esdhc_suspend(struct device *dev) > static int sdhci_esdhc_resume(struct device *dev) > { > struct sdhci_host *host = dev_get_drvdata(dev); > + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host); > + struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host); > int ret; > > ret = pinctrl_pm_select_default_state(dev); > @@ -1777,8 +1818,11 @@ static int sdhci_esdhc_resume(struct device *dev) > if (ret) > return ret; > > - if (host->mmc->caps2 & MMC_CAP2_CQE) > + if (host->mmc->caps2 & MMC_CAP2_CQE) { > ret = cqhci_resume(host->mmc); > + } else if (esdhc_is_usdhc(imx_data)) { > + mmc_hsq_resume(host->mmc); > + } > > if (!ret) > ret = mmc_gpio_set_cd_wake(host->mmc, false); > @@ -1799,6 +1843,8 @@ static int sdhci_esdhc_runtime_suspend(struct device *dev) > ret = cqhci_suspend(host->mmc); > if (ret) > return ret; > + } else if (esdhc_is_usdhc(imx_data)) { > + mmc_hsq_suspend(host->mmc); > } > > ret = sdhci_runtime_suspend_host(host); > @@ -1851,8 +1897,11 @@ static int sdhci_esdhc_runtime_resume(struct device *dev) > if (err) > goto disable_ipg_clk; > > - if (host->mmc->caps2 & MMC_CAP2_CQE) > + if (host->mmc->caps2 & MMC_CAP2_CQE) { > err = cqhci_resume(host->mmc); > + } else if (esdhc_is_usdhc(imx_data)) { > + mmc_hsq_resume(host->mmc); > + } > > return err; > > > > > > > Changes from v8: > > > > - Add more description in the commit message. > > > > - Optimize the failure log when calling cqe_enable(). > > > > > > > > Changes from v7: > > > > - Add reviewed tag from Arnd. > > > > - Use the 'hsq' acronym for varibles and functions in the core layer. > > > > - Check the 'card->ext_csd.cmdq_en' in cqhci.c to make sure the CQE > > > > can work normally. > > > > - Add a new patch to enable the host software queue for the SD card. > > > > - Use the default MMC queue depth for host software queue. > > > > > > > > Changes from v6: > > > > - Change the patch order and set host->always_defer_done = true for > > > > the Spreadtrum host driver. > > > > > > > > Changes from v5: > > > > - Modify the condition of defering to complete request suggested by > > Adrian. > > > > > > > > Changes from v4: > > > > - Add a seperate patch to introduce a variable to defer to complete > > > > data requests for some host drivers, when using host software queue. > > > > > > > > Changes from v3: > > > > - Use host software queue instead of sqhci. > > > > - Fix random config building issue. > > > > - Change queue depth to 32, but still only allow 2 requests in flight. > > > > - Update the testing data. > > > > > > > > Changes from v2: > > > > - Remove reference to 'struct cqhci_host' and 'struct cqhci_slot', > > > > instead adding 'struct sqhci_host', which is only used by software queue. > > > > > > > > Changes from v1: > > > > - Add request_done ops for sdhci_ops. > > > > - Replace virtual command queue with software queue for functions > > > > and variables. > > > > - Rename the software queue file and add sqhci.h header file. > > > > > > > > Baolin Wang (5): > > > > mmc: Add MMC host software queue support > > > > mmc: core: Enable the MMC host software queue for the SD card > > > > mmc: host: sdhci: Add request_done ops for struct sdhci_ops > > > > mmc: host: sdhci: Add a variable to defer to complete requests if > > > > needed > > > > mmc: host: sdhci-sprd: Add software queue support > > > > > > > > drivers/mmc/core/block.c | 61 ++++++++ > > > > drivers/mmc/core/mmc.c | 18 ++- > > > > drivers/mmc/core/queue.c | 22 ++- > > > > drivers/mmc/core/sd.c | 10 ++ > > > > drivers/mmc/host/Kconfig | 8 + > > > > drivers/mmc/host/Makefile | 1 + > > > > drivers/mmc/host/cqhci.c | 8 +- > > > > drivers/mmc/host/mmc_hsq.c | 343 > > +++++++++++++++++++++++++++++++++++++++++ > > > > drivers/mmc/host/mmc_hsq.h | 30 ++++ > > > > drivers/mmc/host/sdhci-sprd.c | 28 ++++ > > > > drivers/mmc/host/sdhci.c | 14 +- > > > > drivers/mmc/host/sdhci.h | 3 + > > > > include/linux/mmc/host.h | 3 + > > > > 13 files changed, 534 insertions(+), 15 deletions(-) create mode > > > > 100644 drivers/mmc/host/mmc_hsq.c create mode 100644 > > > > drivers/mmc/host/mmc_hsq.h > > > > > > > > -- > > > > 1.7.9.5 > > > > > > > > > > Applied for next, thanks! Also, thanks for your patience while moving > > > forward during the reviews! > > > > I am very appreciated for you and Arnd's good sugestion when introducing the > > hsq. > > > > > > > > Note, I did some amending of patch1 to resolve some checkpatch > > > warnings. SPDX licence and Kconfig help texts, please have a look and > > > tell if there are something that doesn't look good. > > > > Thanks for your help and looks good to me. -- Baolin Wang
