From patchwork Fri Sep 22 09:38:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenchao Hao X-Patchwork-Id: 13395457 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5E78CD4F42 for ; Fri, 22 Sep 2023 09:39:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232890AbjIVJjP (ORCPT ); Fri, 22 Sep 2023 05:39:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233253AbjIVJjO (ORCPT ); Fri, 22 Sep 2023 05:39:14 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A53C51A1; Fri, 22 Sep 2023 02:39:07 -0700 (PDT) Received: from kwepemm000012.china.huawei.com (unknown [172.30.72.53]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4RsRxP42zKz15NSB; Fri, 22 Sep 2023 17:36:57 +0800 (CST) Received: from build.huawei.com (10.175.101.6) by kwepemm000012.china.huawei.com (7.193.23.142) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 22 Sep 2023 17:39:05 +0800 From: Wenchao Hao To: "James E . J . Bottomley" , "Martin K . Petersen" , , CC: , , Wenchao Hao Subject: [PATCH 1/2] scsi: core: cleanup scsi_dev_queue_ready() Date: Fri, 22 Sep 2023 17:38:41 +0800 Message-ID: <20230922093842.2646157-2-haowenchao2@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20230922093842.2646157-1-haowenchao2@huawei.com> References: <20230922093842.2646157-1-haowenchao2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm000012.china.huawei.com (7.193.23.142) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org This is just a cleanup for scsi_dev_queue_ready() to avoid redundant goto and if statement, it did not change the origin logic. Signed-off-by: Wenchao Hao --- drivers/scsi/scsi_lib.c | 35 ++++++++++++++++++----------------- 1 file changed, 18 insertions(+), 17 deletions(-) diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index ca5eb058d5c7..f3e388127dbd 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1254,28 +1254,29 @@ static inline int scsi_dev_queue_ready(struct request_queue *q, int token; token = sbitmap_get(&sdev->budget_map); - if (atomic_read(&sdev->device_blocked)) { - if (token < 0) - goto out; + if (token < 0) + return -1; - if (scsi_device_busy(sdev) > 1) - goto out_dec; + /* + * device_blocked is not set at mostly time, so check it first + * and return token when it is not set. + */ + if (!atomic_read(&sdev->device_blocked)) + return token; - /* - * unblock after device_blocked iterates to zero - */ - if (atomic_dec_return(&sdev->device_blocked) > 0) - goto out_dec; - SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev, - "unblocking device at zero depth\n")); + /* + * unblock after device_blocked iterates to zero + */ + if (scsi_device_busy(sdev) > 1 || + atomic_dec_return(&sdev->device_blocked) > 0) { + sbitmap_put(&sdev->budget_map, token); + return -1; } + SCSI_LOG_MLQUEUE(3, sdev_printk(KERN_INFO, sdev, + "unblocking device at zero depth\n")); + return token; -out_dec: - if (token >= 0) - sbitmap_put(&sdev->budget_map, token); -out: - return -1; } /* From patchwork Fri Sep 22 09:38:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wenchao Hao X-Patchwork-Id: 13395458 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8ECF0CD4F43 for ; Fri, 22 Sep 2023 09:39:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233279AbjIVJjQ (ORCPT ); Fri, 22 Sep 2023 05:39:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233236AbjIVJjO (ORCPT ); Fri, 22 Sep 2023 05:39:14 -0400 Received: from szxga03-in.huawei.com (szxga03-in.huawei.com [45.249.212.189]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5A91D1A8; Fri, 22 Sep 2023 02:39:08 -0700 (PDT) Received: from kwepemm000012.china.huawei.com (unknown [172.30.72.56]) by szxga03-in.huawei.com (SkyGuard) with ESMTP id 4RsRvj2s01zMlmt; Fri, 22 Sep 2023 17:35:29 +0800 (CST) Received: from build.huawei.com (10.175.101.6) by kwepemm000012.china.huawei.com (7.193.23.142) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.31; Fri, 22 Sep 2023 17:39:06 +0800 From: Wenchao Hao To: "James E . J . Bottomley" , "Martin K . Petersen" , , CC: , , Wenchao Hao Subject: [PATCH 2/2] scsi: Add comment of target_destroy in scsi_host_template Date: Fri, 22 Sep 2023 17:38:42 +0800 Message-ID: <20230922093842.2646157-3-haowenchao2@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20230922093842.2646157-1-haowenchao2@huawei.com> References: <20230922093842.2646157-1-haowenchao2@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.175.101.6] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To kwepemm000012.china.huawei.com (7.193.23.142) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org Add comment to tell callback function target_destroy of scsi_host_template is called in atomic context. Signed-off-by: Wenchao Hao --- include/scsi/scsi_host.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h index 49f768d0ff37..a72248fa5adf 100644 --- a/include/scsi/scsi_host.h +++ b/include/scsi/scsi_host.h @@ -245,6 +245,9 @@ struct scsi_host_template { * midlayer calls this point so that the driver may deallocate * and terminate any references to the target. * + * Note: this callback in called with spin_lock held, so donot + * call functions might cause schedule + * * Status: OPTIONAL */ void (* target_destroy)(struct scsi_target *);