From patchwork Fri Dec 31 02:08:23 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Douglas Gilbert X-Patchwork-Id: 529732 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 480E6C433FE for ; Fri, 31 Dec 2021 02:16:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242557AbhLaCQR (ORCPT ); Thu, 30 Dec 2021 21:16:17 -0500 Received: from smtp.infotech.no ([82.134.31.41]:46083 "EHLO smtp.infotech.no" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242548AbhLaCQM (ORCPT ); Thu, 30 Dec 2021 21:16:12 -0500 Received: from localhost (localhost [127.0.0.1]) by smtp.infotech.no (Postfix) with ESMTP id E58512041D7; Fri, 31 Dec 2021 03:08:40 +0100 (CET) X-Virus-Scanned: by amavisd-new-2.6.6 (20110518) (Debian) at infotech.no Received: from smtp.infotech.no ([127.0.0.1]) by localhost (smtp.infotech.no [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Bww5kC7yfqSP; Fri, 31 Dec 2021 03:08:39 +0100 (CET) Received: from xtwo70.bingwo.ca (host-45-58-208-241.dyn.295.ca [45.58.208.241]) by smtp.infotech.no (Postfix) with ESMTPA id 868D62041BB; Fri, 31 Dec 2021 03:08:34 +0100 (CET) From: Douglas Gilbert To: linux-scsi@vger.kernel.org Cc: martin.petersen@oracle.com, jejb@linux.vnet.ibm.com Subject: [PATCH 3/9] scsi_debug: use task set full more Date: Thu, 30 Dec 2021 21:08:23 -0500 Message-Id: <20211231020829.29147-4-dgilbert@interlog.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211231020829.29147-1-dgilbert@interlog.com> References: <20211231020829.29147-1-dgilbert@interlog.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org When the internal in_use bit array in this driver is full returning SCSI_MLQUEUE_HOST_BUSY leads to the mid-level re-issueing the request which is unhelpful. Previously TASK SET FULL status was only returned if ALL_TSF [0x400] is placed in the opts variable (at load time or via sysfs). Now ignore that setting and always return TASK SET FULL when in_use array is full. Also set DID_ABORT together with TASK SET FULL so the mid-level gives up immediately. Aside: the situations addressed by this patch lead to lockups and timeouts. They have only been detected when blk_poll() is used. That mechanism is relatively new in the SCSI subsystem suggesting the mid-level may need more work in that area. Signed-off-by: Douglas Gilbert --- drivers/scsi/scsi_debug.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 3fb9e0072627..6d50d248ff3a 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -174,7 +174,7 @@ static const char *sdebug_version_date = "20200710"; #define SDEBUG_OPT_MAC_TIMEOUT 128 #define SDEBUG_OPT_SHORT_TRANSFER 0x100 #define SDEBUG_OPT_Q_NOISE 0x200 -#define SDEBUG_OPT_ALL_TSF 0x400 +#define SDEBUG_OPT_ALL_TSF 0x400 /* ignore */ #define SDEBUG_OPT_RARE_TSF 0x800 #define SDEBUG_OPT_N_WCE 0x1000 #define SDEBUG_OPT_RESET_NOISE 0x2000 @@ -861,7 +861,7 @@ static const int illegal_condition_result = (DID_ABORT << 16) | SAM_STAT_CHECK_CONDITION; static const int device_qfull_result = - (DID_OK << 16) | SAM_STAT_TASK_SET_FULL; + (DID_ABORT << 16) | SAM_STAT_TASK_SET_FULL; static const int condition_met_result = SAM_STAT_CONDITION_MET; @@ -5521,18 +5521,11 @@ static int schedule_resp(struct scsi_cmnd *cmnd, struct sdebug_dev_info *devip, spin_unlock_irqrestore(&sqp->qc_lock, iflags); if (scsi_result) goto respond_in_thread; - else if (SDEBUG_OPT_ALL_TSF & sdebug_opts) - scsi_result = device_qfull_result; + scsi_result = device_qfull_result; if (SDEBUG_OPT_Q_NOISE & sdebug_opts) - sdev_printk(KERN_INFO, sdp, - "%s: max_queue=%d exceeded, %s\n", - __func__, sdebug_max_queue, - (scsi_result ? "status: TASK SET FULL" : - "report: host busy")); - if (scsi_result) - goto respond_in_thread; - else - return SCSI_MLQUEUE_HOST_BUSY; + sdev_printk(KERN_INFO, sdp, "%s: max_queue=%d exceeded: TASK SET FULL\n", + __func__, sdebug_max_queue); + goto respond_in_thread; } set_bit(k, sqp->in_use_bm); atomic_inc(&devip->num_in_q);