From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xbpYL2Q8YzDqNm for ; Tue, 22 Aug 2017 08:40:22 +1000 (AEST) Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v7LMcmqm016685 for ; Mon, 21 Aug 2017 18:40:20 -0400 Received: from e34.co.us.ibm.com (e34.co.us.ibm.com [32.97.110.152]) by mx0a-001b2d01.pphosted.com with ESMTP id 2cg5jxyj5x-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Mon, 21 Aug 2017 18:40:19 -0400 Received: from localhost by e34.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 21 Aug 2017 16:40:19 -0600 Subject: [PATCHv2 1/2] scsi: Move scsi_cmd->jiffies_at_alloc initialization to allocation time From: Brian King To: Bart Van Assche , "linuxppc-dev@lists.ozlabs.org" , "abdhalee@linux.vnet.ibm.com" Cc: "linux-kernel@vger.kernel.org" , "hch@lst.de" , "linux-scsi@vger.kernel.org" , "sfr@canb.auug.org.au" , "sachinp@linux.vnet.ibm.com" , "linux-next@vger.kernel.org" , "hare@suse.com" , "mpe@ellerman.id.au" References: <1502902815.3305.22.camel@abdul.in.ibm.com> <1502904072.2421.3.camel@wdc.com> <2f686064-3e32-df8d-134f-962b5181da9d@linux.vnet.ibm.com> <1502985161.2615.8.camel@wdc.com> <71fb9c1b-9f3f-acdc-8bb5-aa1240aea763@linux.vnet.ibm.com> <1503092473.2622.17.camel@wdc.com> <0f7e2114-eba1-f149-ea80-d32d8b6d212a@linux.vnet.ibm.com> <1503094414.2622.21.camel@wdc.com> <21928108-3a20-577e-99c8-6da05637c158@linux.vnet.ibm.com> Date: Mon, 21 Aug 2017 17:40:14 -0500 MIME-Version: 1.0 In-Reply-To: <21928108-3a20-577e-99c8-6da05637c158@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8 Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This second version also sets up jiffies_at_alloc in scsi_init_request. This has been tested without the second patch in the series and I've confirmed I now see the following in the logs after booting: [ 121.718088] sd 1:2:0:0: timing out command, waited 120s [ 121.798081] sd 1:2:1:0: timing out command, waited 120s Without this patch I was never seeing these messages, indicating the retry timer code wasn't working. Also, after seeing these messages, I've confirmed there are no longer any hung tasks in the kernel with sysrq-w, while before, without this patch, I would see hung tasks for the scsi_report_opcodes calls which were getting retried forever. 8< Move the initialization of scsi_cmd->jiffies_at_alloc to allocation time rather than prep time. Also ensure that jiffies_at_alloc is preserved when we go through prep. This lets us send retries through prep again and not break the overall retry timer logic in scsi_softirq_done. Suggested-by: Bart Van Assche Signed-off-by: Brian King --- Index: linux-2.6.git/drivers/scsi/scsi_lib.c =================================================================== --- linux-2.6.git.orig/drivers/scsi/scsi_lib.c +++ linux-2.6.git/drivers/scsi/scsi_lib.c @@ -1154,6 +1154,7 @@ void scsi_init_command(struct scsi_devic void *buf = cmd->sense_buffer; void *prot = cmd->prot_sdb; unsigned int unchecked_isa_dma = cmd->flags & SCMD_UNCHECKED_ISA_DMA; + unsigned long jiffies_at_alloc = cmd->jiffies_at_alloc; /* zero out the cmd, except for the embedded scsi_request */ memset((char *)cmd + sizeof(cmd->req), 0, @@ -1164,7 +1165,7 @@ void scsi_init_command(struct scsi_devic cmd->prot_sdb = prot; cmd->flags = unchecked_isa_dma; INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); - cmd->jiffies_at_alloc = jiffies; + cmd->jiffies_at_alloc = jiffies_at_alloc; scsi_add_cmd_to_list(cmd); } @@ -2016,6 +2017,7 @@ static int scsi_init_request(struct blk_ if (!cmd->sense_buffer) return -ENOMEM; cmd->req.sense = cmd->sense_buffer; + cmd->jiffies_at_alloc = jiffies; if (scsi_host_get_prot(shost)) { sg = (void *)cmd + sizeof(struct scsi_cmnd) + @@ -2119,6 +2121,7 @@ static int scsi_init_rq(struct request_q if (!cmd->sense_buffer) goto fail; cmd->req.sense = cmd->sense_buffer; + cmd->jiffies_at_alloc = jiffies; if (scsi_host_get_prot(shost) >= SHOST_DIX_TYPE0_PROTECTION) { cmd->prot_sdb = kmem_cache_zalloc(scsi_sdb_cache, gfp);