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=-8.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS 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 DD8E1C433E0 for ; Wed, 17 Mar 2021 04:42:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D5B764F9E for ; Wed, 17 Mar 2021 04:42:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229587AbhCQElr (ORCPT ); Wed, 17 Mar 2021 00:41:47 -0400 Received: from m42-10.mailgun.net ([69.72.42.10]:32508 "EHLO m42-10.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229540AbhCQEl1 (ORCPT ); Wed, 17 Mar 2021 00:41:27 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1615956087; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=eGTA0+I6gJJJ1efJFiJ/1XC/rmCP98XQ3G6teytT6zA=; b=FOfG4cJG0JprU89SIns7N+z9qYQbB8NrCYl9Vb4HyAIVTSohA+DVi7sBlXnBbk2KRzZn1HY7 onE2u45MS8Pv1UCnFeAYjdwOb2GtgH9v5L6iqdEQ32rg26c7fWGp9XGktc70SsbKhzzQ0k86 dZMBEiUrqAVNSgnuPrrKE/a1JgU= X-Mailgun-Sending-Ip: 69.72.42.10 X-Mailgun-Sid: WyI0MWYwYSIsICJsaW51eC1rZXJuZWxAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n05.prod.us-east-1.postgun.com with SMTP id 605188704db3bb68016708ae (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 17 Mar 2021 04:41:20 GMT Sender: cang=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 1147EC43463; Wed, 17 Mar 2021 04:41:19 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id E73C9C433C6; Wed, 17 Mar 2021 04:41:18 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 17 Mar 2021 12:41:18 +0800 From: Can Guo To: daejun7.park@samsung.com Cc: Avri Altman , "James E . J . Bottomley" , "Martin K . Petersen" , linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, Bart Van Assche , yongmyung lee , ALIM AKHTAR , asutoshd@codeaurora.org, Zang Leigang , Avi Shchislowski , Bean Huo , stanley.chu@mediatek.com Subject: Re: [PATCH v5 05/10] scsi: ufshpb: Region inactivation in host mode In-Reply-To: <2038148563.21615949282962.JavaMail.epsvc@epcpadp4> References: <20210302132503.224670-1-avri.altman@wdc.com> <20210302132503.224670-6-avri.altman@wdc.com> <25da7378d5bf4c52443ae9b47f3fd778@codeaurora.org> <57afb2b5d7edda61a40493d8545785b1@codeaurora.org> <2038148563.21615949282962.JavaMail.epsvc@epcpadp4> Message-ID: <064483451ff0d9ef8703871332ea5c3b@codeaurora.org> X-Sender: cang@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021-03-17 10:28, Daejun Park wrote: >>> >> --- >>> >> drivers/scsi/ufs/ufshpb.c | 14 ++++++++++++++ >>> >> drivers/scsi/ufs/ufshpb.h | 1 + >>> >> 2 files changed, 15 insertions(+) >>> >> >>> >> diff --git a/drivers/scsi/ufs/ufshpb.c b/drivers/scsi/ufs/ufshpb.c >>> >> index 6f4fd22eaf2f..0744feb4d484 100644 >>> >> --- a/drivers/scsi/ufs/ufshpb.c >>> >> +++ b/drivers/scsi/ufs/ufshpb.c >>> >> @@ -907,6 +907,7 @@ static int ufshpb_execute_umap_req(struct >>> >> ufshpb_lu *hpb, >>> >> >>> >> blk_execute_rq_nowait(q, NULL, req, 1, ufshpb_umap_req_compl_fn); >>> >> >>> >> + hpb->stats.umap_req_cnt++; >>> >> return 0; >>> >> } >>> >> >>> >> @@ -1103,6 +1104,12 @@ static int ufshpb_issue_umap_req(struct >>> >> ufshpb_lu *hpb, >>> >> return -EAGAIN; >>> >> } >>> >> >>> >> +static int ufshpb_issue_umap_single_req(struct ufshpb_lu *hpb, >>> >> + struct ufshpb_region *rgn) >>> >> +{ >>> >> + return ufshpb_issue_umap_req(hpb, rgn); >>> >> +} >>> >> + >>> >> static int ufshpb_issue_umap_all_req(struct ufshpb_lu *hpb) >>> >> { >>> >> return ufshpb_issue_umap_req(hpb, NULL); >>> >> @@ -1115,6 +1122,10 @@ static void __ufshpb_evict_region(struct >>> >> ufshpb_lu *hpb, >>> >> struct ufshpb_subregion *srgn; >>> >> int srgn_idx; >>> >> >>> >> + >>> >> + if (hpb->is_hcm && ufshpb_issue_umap_single_req(hpb, rgn)) >>> > >>> > __ufshpb_evict_region() is called with rgn_state_lock held and IRQ >>> > disabled, >>> > when ufshpb_issue_umap_single_req() invokes blk_execute_rq_nowait(), >>> > below >>> > warning shall pop up every time, fix it? >>> > >>> > void blk_execute_rq_nowait(struct request_queue *q, struct gendisk >>> > *bd_disk, >>> > struct request *rq, int at_head, >>> > rq_end_io_fn *done) >>> > { >>> > WARN_ON(irqs_disabled()); >>> > ... >>> > >>> >>> Moreover, since we are here with rgn_state_lock held and IRQ >>> disabled, >>> in ufshpb_get_req(), rq = kmem_cache_alloc(hpb->map_req_cache, >>> GFP_KERNEL) >>> has the GFP_KERNEL flag, scheduling while atomic??? >> I think your comment applies to ufshpb_issue_umap_all_req as well, >> Which is called from slave_configure/scsi_add_lun. >> >> Since the host-mode series is utilizing the framework laid by the >> device-mode, >> Maybe you can add this comment to Daejun's last version? > > Hi Avri, Can Guo > > I think ufshpb_issue_umap_single_req() can be moved to end of > ufshpb_evict_region(). > Then we can avoid rgn_state_lock when it sends unmap command. I am not the expert here, please you two fix it. I am just reporting what can be wrong. Anyways, ufshpb_issue_umap_single_req() should not be called with rgn_state_lock held - think about below (another deadly) scenario. lock(rgn_state_lock) ufshpb_issue_umap_single_req() ufshpb_prep() lock(rgn_state_lock) <---------- recursive spin_lock BTW, @Daejun shouldn't we stop passthrough cmds from stepping into ufshpb_prep()? In current code, you are trying to use below check to block cmds other than write/discard/read, but a passthrough cmd can not be blocked by the check. if (!ufshpb_is_write_or_discard_cmd(cmd) && !ufshpb_is_read_cmd(cmd)) return 0; Thanks, Can Guo. > > Thanks, > Daejun > > >> Thanks, >> Avri >> >>> >>> Can Guo. >>> >>> > Thanks. >>> > Can Guo. >>> > >>> >> + return; >>> >> + >>> >> lru_info = &hpb->lru_info; >>> >> >>> >> dev_dbg(&hpb->sdev_ufs_lu->sdev_dev, "evict region %d\n", >>> >> rgn->rgn_idx); >>> >> @@ -1855,6 +1866,7 @@ ufshpb_sysfs_attr_show_func(rb_noti_cnt); >>> >> ufshpb_sysfs_attr_show_func(rb_active_cnt); >>> >> ufshpb_sysfs_attr_show_func(rb_inactive_cnt); >>> >> ufshpb_sysfs_attr_show_func(map_req_cnt); >>> >> +ufshpb_sysfs_attr_show_func(umap_req_cnt); >>> >> >>> >> static struct attribute *hpb_dev_stat_attrs[] = { >>> >> &dev_attr_hit_cnt.attr, >>> >> @@ -1863,6 +1875,7 @@ static struct attribute *hpb_dev_stat_attrs[] = >>> >> { >>> >> &dev_attr_rb_active_cnt.attr, >>> >> &dev_attr_rb_inactive_cnt.attr, >>> >> &dev_attr_map_req_cnt.attr, >>> >> + &dev_attr_umap_req_cnt.attr, >>> >> NULL, >>> >> }; >>> >> >>> >> @@ -1978,6 +1991,7 @@ static void ufshpb_stat_init(struct ufshpb_lu >>> >> *hpb) >>> >> hpb->stats.rb_active_cnt = 0; >>> >> hpb->stats.rb_inactive_cnt = 0; >>> >> hpb->stats.map_req_cnt = 0; >>> >> + hpb->stats.umap_req_cnt = 0; >>> >> } >>> >> >>> >> static void ufshpb_param_init(struct ufshpb_lu *hpb) >>> >> diff --git a/drivers/scsi/ufs/ufshpb.h b/drivers/scsi/ufs/ufshpb.h >>> >> index bd4308010466..84598a317897 100644 >>> >> --- a/drivers/scsi/ufs/ufshpb.h >>> >> +++ b/drivers/scsi/ufs/ufshpb.h >>> >> @@ -186,6 +186,7 @@ struct ufshpb_stats { >>> >> u64 rb_inactive_cnt; >>> >> u64 map_req_cnt; >>> >> u64 pre_req_cnt; >>> >> + u64 umap_req_cnt; >>> >> }; >>> >> >>> >> struct ufshpb_lu { >> >> >>