From patchwork Thu Feb 21 09:18:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Benjamin Block X-Patchwork-Id: 10823327 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0720D14E1 for ; Thu, 21 Feb 2019 09:18:15 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E8159301EA for ; Thu, 21 Feb 2019 09:18:14 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D917B3020A; Thu, 21 Feb 2019 09:18:14 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B965F301EA for ; Thu, 21 Feb 2019 09:18:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727489AbfBUJSL (ORCPT ); Thu, 21 Feb 2019 04:18:11 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:60614 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726514AbfBUJSL (ORCPT ); Thu, 21 Feb 2019 04:18:11 -0500 Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x1L96Kjd056612 for ; Thu, 21 Feb 2019 04:18:09 -0500 Received: from e06smtp02.uk.ibm.com (e06smtp02.uk.ibm.com [195.75.94.98]) by mx0b-001b2d01.pphosted.com with ESMTP id 2qsqx4ktr9-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Thu, 21 Feb 2019 04:18:09 -0500 Received: from localhost by e06smtp02.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Thu, 21 Feb 2019 09:18:04 -0000 Received: from d06av26.portsmouth.uk.ibm.com (d06av26.portsmouth.uk.ibm.com [9.149.105.62]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x1L9I3We29491302 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Thu, 21 Feb 2019 09:18:03 GMT Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 43022AE04D; Thu, 21 Feb 2019 09:18:03 +0000 (GMT) Received: from d06av26.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 2E9BFAE045; Thu, 21 Feb 2019 09:18:03 +0000 (GMT) Received: from t480-pf1aa2c2 (unknown [9.145.59.126]) by d06av26.portsmouth.uk.ibm.com (Postfix) with ESMTPS; Thu, 21 Feb 2019 09:18:03 +0000 (GMT) Received: from bblock by t480-pf1aa2c2 with local (Exim 4.91) (envelope-from ) id 1gwkUU-0006fp-CY; Thu, 21 Feb 2019 10:18:02 +0100 From: Benjamin Block To: "James E . J . Bottomley" , "Martin K . Petersen" Cc: Benjamin Block , Steffen Maier , linux-scsi@vger.kernel.org, linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org, Bart Van Assche Subject: [PATCH v2 1/2] scsi: replace GFP_ATOMIC with GFP_KERNEL for allocations in scsi_scan.c Date: Thu, 21 Feb 2019 10:18:00 +0100 X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190220184847.24640-1-bblock@linux.ibm.com> References: <20190220184847.24640-1-bblock@linux.ibm.com> MIME-Version: 1.0 X-TM-AS-GCONF: 00 x-cbid: 19022109-0008-0000-0000-000002C31C86 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19022109-0009-0000-0000-0000222F5666 Message-Id: X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-02-21_06:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=2 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1902210068 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We had a test-report where, under memory pressure, adding LUNs to the systems would fail (the tests add LUNs strictly in sequence): [ 5525.853432] scsi 0:0:1:1088045124: Direct-Access IBM 2107900 .148 PQ: 0 ANSI: 5 [ 5525.853826] scsi 0:0:1:1088045124: alua: supports implicit TPGS [ 5525.853830] scsi 0:0:1:1088045124: alua: device naa.6005076303ffd32700000000000044da port group 0 rel port 43 [ 5525.853931] sd 0:0:1:1088045124: Attached scsi generic sg10 type 0 [ 5525.854075] sd 0:0:1:1088045124: [sdk] Disabling DIF Type 1 protection [ 5525.855495] sd 0:0:1:1088045124: [sdk] 2097152 512-byte logical blocks: (1.07 GB/1.00 GiB) [ 5525.855606] sd 0:0:1:1088045124: [sdk] Write Protect is off [ 5525.855609] sd 0:0:1:1088045124: [sdk] Mode Sense: ed 00 00 08 [ 5525.855795] sd 0:0:1:1088045124: [sdk] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA [ 5525.857838] sdk: sdk1 [ 5525.859468] sd 0:0:1:1088045124: [sdk] Attached SCSI disk [ 5525.865073] sd 0:0:1:1088045124: alua: transition timeout set to 60 seconds [ 5525.865078] sd 0:0:1:1088045124: alua: port group 00 state A preferred supports tolusnA [ 5526.015070] sd 0:0:1:1088045124: alua: port group 00 state A preferred supports tolusnA [ 5526.015213] sd 0:0:1:1088045124: alua: port group 00 state A preferred supports tolusnA [ 5526.587439] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured [ 5526.588562] scsi_alloc_sdev: Allocation failure during SCSI scanning, some SCSI devices might not be configured Looking at the code of scsi_alloc_sdev(), and all the calling contexts, there seems to be no reason to use GFP_ATMOIC here. All the different call-contexts use a mutex at some point, and nothing in between that requires no sleeping, as far as I could see. Additionally, the code that later allocates the block queue for the device (scsi_mq_alloc_queue()) already uses GFP_KERNEL. There are similar allocations in two other functions: scsi_probe_and_add_lun(), and scsi_add_lun(),; that can also be done with GFP_KERNEL. Here is the contexts for the three functions so far: scsi_alloc_sdev() scsi_probe_and_add_lun() scsi_sequential_lun_scan() __scsi_scan_target() scsi_scan_target() mutex_lock() scsi_scan_channel() scsi_scan_host_selected() mutex_lock() scsi_report_lun_scan() __scsi_scan_target() ... __scsi_add_device() mutex_lock() __scsi_scan_target() ... scsi_report_lun_scan() ... scsi_get_host_dev() mutex_lock() scsi_probe_and_add_lun() ... scsi_add_lun() scsi_probe_and_add_lun() ... So replace all these, and give them a bit of a better chance to succeed, with more chances of reclaim. Signed-off-by: Benjamin Block Reviewed-by: Bart Van Assche --- drivers/scsi/scsi_scan.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c index dd0d516f65e2..53380e07b40e 100644 --- a/drivers/scsi/scsi_scan.c +++ b/drivers/scsi/scsi_scan.c @@ -220,7 +220,7 @@ static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget, struct Scsi_Host *shost = dev_to_shost(starget->dev.parent); sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size, - GFP_ATOMIC); + GFP_KERNEL); if (!sdev) goto out; @@ -788,7 +788,7 @@ static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result, */ sdev->inquiry = kmemdup(inq_result, max_t(size_t, sdev->inquiry_len, 36), - GFP_ATOMIC); + GFP_KERNEL); if (sdev->inquiry == NULL) return SCSI_SCAN_NO_RESPONSE; @@ -1079,7 +1079,7 @@ static int scsi_probe_and_add_lun(struct scsi_target *starget, if (!sdev) goto out; - result = kmalloc(result_len, GFP_ATOMIC | + result = kmalloc(result_len, GFP_KERNEL | ((shost->unchecked_isa_dma) ? __GFP_DMA : 0)); if (!result) goto out_free_sdev;