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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 9E76EC47094 for ; Thu, 10 Jun 2021 13:35:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 89F2B613FE for ; Thu, 10 Jun 2021 13:35:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231124AbhFJNgy (ORCPT ); Thu, 10 Jun 2021 09:36:54 -0400 Received: from mga18.intel.com ([134.134.136.126]:31511 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230435AbhFJNgw (ORCPT ); Thu, 10 Jun 2021 09:36:52 -0400 IronPort-SDR: l5TLdD7cGsxIEf4kLEPWMTEPLz31J8RpgiIdSxHcDL43fWCwf06ErFlsxrNvlFGUd7ZDkXQzFN g0+LI8sIzJBA== X-IronPort-AV: E=McAfee;i="6200,9189,10011"; a="192612418" X-IronPort-AV: E=Sophos;i="5.83,263,1616482800"; d="scan'208";a="192612418" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jun 2021 06:32:50 -0700 IronPort-SDR: 7nUpw3RLVnjyioJh0UKy5Niob54pNKBtNcsAgqMkXa/lbEBX7AR284S94bh+XMP7GFHpgFf1mX VIZtpjgBO+Zw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,263,1616482800"; d="scan'208";a="402861024" Received: from ahunter-desktop.fi.intel.com (HELO [10.237.72.79]) ([10.237.72.79]) by orsmga003.jf.intel.com with ESMTP; 10 Jun 2021 06:32:00 -0700 Subject: Re: [PATCH v3 7/9] scsi: ufs: Let host_sem cover the entire system suspend/resume To: Can Guo , asutoshd@codeaurora.org, nguyenb@codeaurora.org, hongwus@codeaurora.org, ziqichen@codeaurora.org, linux-scsi@vger.kernel.org, kernel-team@android.com Cc: Alim Akhtar , Avri Altman , "James E.J. Bottomley" , "Martin K. Petersen" , Stanley Chu , Bean Huo , Jaegeuk Kim , Kiwoong Kim , Satya Tangirala , Bart Van Assche , open list References: <1623300218-9454-1-git-send-email-cang@codeaurora.org> <1623300218-9454-8-git-send-email-cang@codeaurora.org> From: Adrian Hunter Organization: Intel Finland Oy, Registered Address: PL 281, 00181 Helsinki, Business Identity Code: 0357606 - 4, Domiciled in Helsinki Message-ID: <6d31becb-98f8-2302-8ffa-657e6cadd8ec@intel.com> Date: Thu, 10 Jun 2021 16:32:29 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.11.0 MIME-Version: 1.0 In-Reply-To: <1623300218-9454-8-git-send-email-cang@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/06/21 7:43 am, Can Guo wrote: > UFS error handling now is doing more than just re-probing, but also sending > scsi cmds, e.g., for clearing UACs, and recovering runtime PM error, which > may change runtime status of scsi devices. To protect system suspend/resume > from being disturbed by error handling, move the host_sem from wl pm ops > to ufshcd_suspend_prepare() and ufshcd_resume_complete(). Have you checked whether error handling might actually be needed after ufshcd_suspend_prepare()? Wouldn't this complexity go away if we just did recovery directly in __ufshcd_wl_suspend() and __ufshcd_wl_resume()? > > Signed-off-by: Can Guo > --- > drivers/scsi/ufs/ufshcd.c | 8 +++----- > drivers/scsi/ufs/ufshcd.h | 2 +- > 2 files changed, 4 insertions(+), 6 deletions(-) > > diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c > index c418a19..861942b 100644 > --- a/drivers/scsi/ufs/ufshcd.c > +++ b/drivers/scsi/ufs/ufshcd.c > @@ -9060,16 +9060,13 @@ static int ufshcd_wl_suspend(struct device *dev) > ktime_t start = ktime_get(); > > hba = shost_priv(sdev->host); > - down(&hba->host_sem); > > if (pm_runtime_suspended(dev)) > goto out; > > ret = __ufshcd_wl_suspend(hba, UFS_SYSTEM_PM); > - if (ret) { > + if (ret) > dev_err(&sdev->sdev_gendev, "%s failed: %d\n", __func__, ret); > - up(&hba->host_sem); > - } > > out: > if (!ret) > @@ -9102,7 +9099,6 @@ static int ufshcd_wl_resume(struct device *dev) > hba->curr_dev_pwr_mode, hba->uic_link_state); > if (!ret) > hba->is_wl_sys_suspended = false; > - up(&hba->host_sem); > return ret; > } > #endif > @@ -9665,6 +9661,7 @@ void ufshcd_resume_complete(struct device *dev) > ufshcd_rpmb_rpm_put(hba); > hba->rpmb_complete_put = false; > } > + up(&hba->host_sem); > } > EXPORT_SYMBOL_GPL(ufshcd_resume_complete); > > @@ -9691,6 +9688,7 @@ int ufshcd_suspend_prepare(struct device *dev) > ufshcd_rpmb_rpm_get_sync(hba); > hba->rpmb_complete_put = true; > } > + down(&hba->host_sem); > return 0; > } > EXPORT_SYMBOL_GPL(ufshcd_suspend_prepare); > diff --git a/drivers/scsi/ufs/ufshcd.h b/drivers/scsi/ufs/ufshcd.h > index eaebb4e..47da47c 100644 > --- a/drivers/scsi/ufs/ufshcd.h > +++ b/drivers/scsi/ufs/ufshcd.h > @@ -693,7 +693,7 @@ struct ufs_hba_monitor { > * @ee_ctrl_mask: Exception event control mask > * @is_powered: flag to check if HBA is powered > * @shutting_down: flag to check if shutdown has been invoked > - * @host_sem: semaphore used to serialize concurrent contexts > + * @host_sem: semaphore used to avoid concurrency of contexts > * @eh_wq: Workqueue that eh_work works on > * @eh_work: Worker to handle UFS errors that require s/w attention > * @eeh_work: Worker to handle exception events >