From patchwork Mon Nov 12 16:06:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ursula Braun X-Patchwork-Id: 996523 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=linux.ibm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42twc24wH3z9s1x for ; Tue, 13 Nov 2018 03:06:26 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729744AbeKMCAQ (ORCPT ); Mon, 12 Nov 2018 21:00:16 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:55979 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729674AbeKMCAQ (ORCPT ); Mon, 12 Nov 2018 21:00:16 -0500 Received: from pps.filterd (m0098409.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.22/8.16.0.22) with SMTP id wACG5Yxa004231 for ; Mon, 12 Nov 2018 11:06:23 -0500 Received: from e06smtp07.uk.ibm.com (e06smtp07.uk.ibm.com [195.75.94.103]) by mx0a-001b2d01.pphosted.com with ESMTP id 2nqa1598r3-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 12 Nov 2018 11:06:23 -0500 Received: from localhost by e06smtp07.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 12 Nov 2018 16:06:20 -0000 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp07.uk.ibm.com (192.168.101.137) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 12 Nov 2018 16:06:17 -0000 Received: from d06av21.portsmouth.uk.ibm.com (d06av21.portsmouth.uk.ibm.com [9.149.105.232]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id wACG6FGQ59244594 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Mon, 12 Nov 2018 16:06:15 GMT Received: from d06av21.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id BF52352059; Mon, 12 Nov 2018 16:06:15 +0000 (GMT) Received: from tuxmaker.boeblingen.de.ibm.com (unknown [9.152.85.9]) by d06av21.portsmouth.uk.ibm.com (Postfix) with ESMTPS id 865CE52057; Mon, 12 Nov 2018 16:06:15 +0000 (GMT) From: Ursula Braun To: davem@davemloft.net Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.ibm.com, ubraun@linux.ibm.com Subject: [PATCH net 1/1] s390/ism: clear dmbe_mask bit before SMC IRQ handling Date: Mon, 12 Nov 2018 17:06:12 +0100 X-Mailer: git-send-email 2.16.4 X-TM-AS-GCONF: 00 x-cbid: 18111216-0028-0000-0000-00000318BA9D X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18111216-0029-0000-0000-000023D51CD6 Message-Id: <20181112160612.31936-1-ubraun@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-11-12_11:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=1 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=809 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1807170000 definitions=main-1811120140 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org SMC-D stress workload showed connection stalls. Since the firmware decides to skip raising an interrupt if the SBA DMBE mask bit is still set, this SBA DMBE mask bit should be cleared before the IRQ handling in the SMC code runs. Otherwise there are small windows possible with missing interrupts for incoming data. SMC-D currently does not care about the old value of the SBA DMBE mask. Acked-by: Sebastian Ott Signed-off-by: Ursula Braun --- drivers/s390/net/ism_drv.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/s390/net/ism_drv.c b/drivers/s390/net/ism_drv.c index f96ec68af2e5..dcbf5c857743 100644 --- a/drivers/s390/net/ism_drv.c +++ b/drivers/s390/net/ism_drv.c @@ -415,9 +415,9 @@ static irqreturn_t ism_handle_irq(int irq, void *data) break; clear_bit_inv(bit, bv); + ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0; barrier(); smcd_handle_irq(ism->smcd, bit + ISM_DMB_BIT_OFFSET); - ism->sba->dmbe_mask[bit + ISM_DMB_BIT_OFFSET] = 0; } if (ism->sba->e) {