diff options
Diffstat (limited to 'mmc-sdio-Use-mmc_pre_req-mmc_post_req.patch')
| -rw-r--r-- | mmc-sdio-Use-mmc_pre_req-mmc_post_req.patch | 156 |
1 files changed, 156 insertions, 0 deletions
diff --git a/mmc-sdio-Use-mmc_pre_req-mmc_post_req.patch b/mmc-sdio-Use-mmc_pre_req-mmc_post_req.patch new file mode 100644 index 000000000..123e2c6f8 --- /dev/null +++ b/mmc-sdio-Use-mmc_pre_req-mmc_post_req.patch @@ -0,0 +1,156 @@ +From patchwork Thu Sep 3 08:20:07 2020 +Content-Type: text/plain; charset="utf-8" +MIME-Version: 1.0 +Content-Transfer-Encoding: 7bit +X-Patchwork-Submitter: Adrian Hunter <adrian.hunter@intel.com> +X-Patchwork-Id: 11752795 +Return-Path: <SRS0=lwnd=CM=vger.kernel.org=linux-mmc-owner@kernel.org> +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 C9EBB14E5 + for <patchwork-linux-mmc@patchwork.kernel.org>; + Thu, 3 Sep 2020 08:20:33 +0000 (UTC) +Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) + by mail.kernel.org (Postfix) with ESMTP id BC26D2071B + for <patchwork-linux-mmc@patchwork.kernel.org>; + Thu, 3 Sep 2020 08:20:33 +0000 (UTC) +Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand + id S1728222AbgICIUc (ORCPT + <rfc822;patchwork-linux-mmc@patchwork.kernel.org>); + Thu, 3 Sep 2020 04:20:32 -0400 +Received: from mga05.intel.com ([192.55.52.43]:36764 "EHLO mga05.intel.com" + rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP + id S1726967AbgICIUc (ORCPT <rfc822;linux-mmc@vger.kernel.org>); + Thu, 3 Sep 2020 04:20:32 -0400 +IronPort-SDR: + UAhQwI9nWr5N0Ssk91Enat0eUs15ciWos+Mpf9aZyd9VfUitB9WC+vPWh1uI8SDDj4GleLaAws + HrPm3i/171hQ== +X-IronPort-AV: E=McAfee;i="6000,8403,9732"; a="242356326" +X-IronPort-AV: E=Sophos;i="5.76,385,1592895600"; + d="scan'208";a="242356326" +X-Amp-Result: SKIPPED(no attachment in message) +X-Amp-File-Uploaded: False +Received: from fmsmga002.fm.intel.com ([10.253.24.26]) + by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; + 03 Sep 2020 01:20:31 -0700 +IronPort-SDR: + us9vTGT33QbxjZoviJb7le3HTC8FOUlIec36VMhX5tXlhCcvcPW9B/SKFJcwEJiMvCa3zvNnDf + 7Vbl3UaoRlmQ== +X-ExtLoop1: 1 +X-IronPort-AV: E=Sophos;i="5.76,385,1592895600"; + d="scan'208";a="334396201" +Received: from slisovsk-lenovo-ideapad-720s-13ikb.fi.intel.com (HELO + ahunter-Desktop.fi.intel.com) ([10.237.72.190]) + by fmsmga002.fm.intel.com with ESMTP; 03 Sep 2020 01:20:29 -0700 +From: Adrian Hunter <adrian.hunter@intel.com> +To: Ulf Hansson <ulf.hansson@linaro.org> +Cc: linux-mmc <linux-mmc@vger.kernel.org>, + =?utf-8?q?Pali_Roh=C3=A1r?= <pali@kernel.org>, + Haibo Chen <haibo.chen@nxp.com>, Yue Hu <huyue2@yulong.com>, + Douglas Anderson <dianders@chromium.org>, Dmitry Osipenko <digetx@gmail.com> +Subject: [PATCH] mmc: sdio: Use mmc_pre_req() / mmc_post_req() +Date: Thu, 3 Sep 2020 11:20:07 +0300 +Message-Id: <20200903082007.18715-1-adrian.hunter@intel.com> +X-Mailer: git-send-email 2.17.1 +Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, + Business Identity Code: 0357606 - 4, Domiciled in Helsinki +Sender: linux-mmc-owner@vger.kernel.org +Precedence: bulk +List-ID: <linux-mmc.vger.kernel.org> +X-Mailing-List: linux-mmc@vger.kernel.org + +SDHCI changed from using a tasklet to finish requests, to using an IRQ +thread i.e. commit c07a48c2651965 ("mmc: sdhci: Remove finish_tasklet"). +Because this increased the latency to complete requests, a preparatory +change was made to complete the request from the IRQ handler if +possible i.e. commit 19d2f695f4e827 ("mmc: sdhci: Call mmc_request_done() +from IRQ handler if possible"). That alleviated the situation for MMC +block devices because the MMC block driver makes use of mmc_pre_req() +and mmc_post_req() so that successful requests are completed in the IRQ +handler and any DMA unmapping is handled separately in mmc_post_req(). +However SDIO was still affected, and an example has been reported with +up to 20% degradation in performance. + +Looking at SDIO I/O helper functions, sdio_io_rw_ext_helper() appeared +to be a possible candidate for making use of asynchronous requests +within its I/O loops, but analysis revealed that these loops almost +never iterate more than once, so the complexity of the change would not +be warrented. + +Instead, mmc_pre_req() and mmc_post_req() are added before and after I/O +submission (mmc_wait_for_req) in mmc_io_rw_extended(). This still has +the potential benefit of reducing the duration of interrupt handlers, as +well as addressing the latency issue for SDHCI. It also seems a more +reasonable solution than forcing drivers to do everything in the IRQ +handler. + +Reported-by: Dmitry Osipenko <digetx@gmail.com> +Fixes: c07a48c2651965 ("mmc: sdhci: Remove finish_tasklet") +Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> +Tested-by: Dmitry Osipenko <digetx@gmail.com> +--- + drivers/mmc/core/sdio_ops.c | 39 +++++++++++++++++++++---------------- + 1 file changed, 22 insertions(+), 17 deletions(-) + +diff --git a/drivers/mmc/core/sdio_ops.c b/drivers/mmc/core/sdio_ops.c +index 93d346c01110..4c229dd2b6e5 100644 +--- a/drivers/mmc/core/sdio_ops.c ++++ b/drivers/mmc/core/sdio_ops.c +@@ -121,6 +121,7 @@ int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn, + struct sg_table sgtable; + unsigned int nents, left_size, i; + unsigned int seg_size = card->host->max_seg_size; ++ int err; + + WARN_ON(blksz == 0); + +@@ -170,28 +171,32 @@ int mmc_io_rw_extended(struct mmc_card *card, int write, unsigned fn, + + mmc_set_data_timeout(&data, card); + +- mmc_wait_for_req(card->host, &mrq); ++ mmc_pre_req(card->host, &mrq); + +- if (nents > 1) +- sg_free_table(&sgtable); ++ mmc_wait_for_req(card->host, &mrq); + + if (cmd.error) +- return cmd.error; +- if (data.error) +- return data.error; +- +- if (mmc_host_is_spi(card->host)) { ++ err = cmd.error; ++ else if (data.error) ++ err = data.error; ++ else if (mmc_host_is_spi(card->host)) + /* host driver already reported errors */ +- } else { +- if (cmd.resp[0] & R5_ERROR) +- return -EIO; +- if (cmd.resp[0] & R5_FUNCTION_NUMBER) +- return -EINVAL; +- if (cmd.resp[0] & R5_OUT_OF_RANGE) +- return -ERANGE; +- } ++ err = 0; ++ else if (cmd.resp[0] & R5_ERROR) ++ err = -EIO; ++ else if (cmd.resp[0] & R5_FUNCTION_NUMBER) ++ err = -EINVAL; ++ else if (cmd.resp[0] & R5_OUT_OF_RANGE) ++ err = -ERANGE; ++ else ++ err = 0; + +- return 0; ++ mmc_post_req(card->host, &mrq, err); ++ ++ if (nents > 1) ++ sg_free_table(&sgtable); ++ ++ return err; + } + + int sdio_reset(struct mmc_host *host) |