From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31F8BC5DF62 for ; Wed, 6 Nov 2019 10:10:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 096ED206A3 for ; Wed, 6 Nov 2019 10:10:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731728AbfKFKKr (ORCPT ); Wed, 6 Nov 2019 05:10:47 -0500 Received: from mga12.intel.com ([192.55.52.136]:20726 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729164AbfKFKKq (ORCPT ); Wed, 6 Nov 2019 05:10:46 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 06 Nov 2019 02:10:46 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.68,274,1569308400"; d="scan'208";a="196154035" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.197]) ([10.237.72.197]) by orsmga008.jf.intel.com with ESMTP; 06 Nov 2019 02:10:42 -0800 Subject: Re: [PATCH v5 4/4] mmc: host: sdhci: Add a variable to defer to complete data requests if needed To: Baolin Wang , ulf.hansson@linaro.org, asutoshd@codeaurora.org Cc: orsonzhai@gmail.com, zhang.lyra@gmail.com, arnd@arndb.de, linus.walleij@linaro.org, vincent.guittot@linaro.org, baolin.wang7@gmail.com, linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org References: <19910a2f34b9be81f64637a5a5fc8d07bd5f4885.1572326519.git.baolin.wang@linaro.org> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: Date: Wed, 6 Nov 2019 12:09:42 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <19910a2f34b9be81f64637a5a5fc8d07bd5f4885.1572326519.git.baolin.wang@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29/10/19 7:43 AM, Baolin Wang wrote: > When using the host software queue, it will trigger the next request in > irq handler without a context switch. But the sdhci_request() can not be > called in interrupt context when using host software queue for some host > drivers, due to the get_cd() ops can be sleepable. > > But for some host drivers, such as Spreadtrum host driver, the card is > nonremovable, so the get_cd() ops is not sleepable, which means we can > complete the data request and trigger the next request in irq handler > to remove the context switch for the Spreadtrum host driver. > > Thus we still need introduce a variable in struct sdhci_host to indicate > that we will always to defer to complete data requests if the sdhci_request() > can not be called in interrupt context for some host drivers, when using > the host software queue. > > Suggested-by: Adrian Hunter > Signed-off-by: Baolin Wang > --- > drivers/mmc/host/sdhci.c | 2 +- > drivers/mmc/host/sdhci.h | 1 + > 2 files changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c > index 850241f..9cf2130 100644 > --- a/drivers/mmc/host/sdhci.c > +++ b/drivers/mmc/host/sdhci.c > @@ -3035,7 +3035,7 @@ static inline bool sdhci_defer_done(struct sdhci_host *host, > { > struct mmc_data *data = mrq->data; > > - return host->pending_reset || > + return host->pending_reset || (host->always_defer_done && data) || I didn't realize you still wanted to call the request function in interrupt context. In my view that needs a new host API i.e. int (*request_atomic)(struct mmc_host *mmc, struct mmc_request *mrq) > ((host->flags & SDHCI_REQ_USE_DMA) && data && > data->host_cookie == COOKIE_MAPPED); > } > diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h > index d89cdb9..38fbd18 100644 > --- a/drivers/mmc/host/sdhci.h > +++ b/drivers/mmc/host/sdhci.h > @@ -533,6 +533,7 @@ struct sdhci_host { > bool pending_reset; /* Cmd/data reset is pending */ > bool irq_wake_enabled; /* IRQ wakeup is enabled */ > bool v4_mode; /* Host Version 4 Enable */ > + bool always_defer_done; /* Always defer to complete data requests */ > > struct mmc_request *mrqs_done[SDHCI_MAX_MRQS]; /* Requests done */ > struct mmc_command *cmd; /* Current command */ >