From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E302BC04AB3 for ; Mon, 27 May 2019 12:03:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BD3CB20883 for ; Mon, 27 May 2019 12:03:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726490AbfE0MD3 (ORCPT ); Mon, 27 May 2019 08:03:29 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:43884 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726071AbfE0MD3 (ORCPT ); Mon, 27 May 2019 08:03:29 -0400 Received: from pps.filterd (m0098394.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4RBrLCC038625 for ; Mon, 27 May 2019 08:03:28 -0400 Received: from e06smtp03.uk.ibm.com (e06smtp03.uk.ibm.com [195.75.94.99]) by mx0a-001b2d01.pphosted.com with ESMTP id 2srdcq7f6a-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Mon, 27 May 2019 08:03:28 -0400 Received: from localhost by e06smtp03.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Mon, 27 May 2019 13:03:25 +0100 Received: from b06cxnps3075.portsmouth.uk.ibm.com (9.149.109.195) by e06smtp03.uk.ibm.com (192.168.101.133) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Mon, 27 May 2019 13:03:22 +0100 Received: from d06av24.portsmouth.uk.ibm.com (d06av24.portsmouth.uk.ibm.com [9.149.105.60]) by b06cxnps3075.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id x4RC3KOC50790566 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 27 May 2019 12:03:20 GMT Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 74ED44204D; Mon, 27 May 2019 12:03:20 +0000 (GMT) Received: from d06av24.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 31ABC42047; Mon, 27 May 2019 12:03:19 +0000 (GMT) Received: from oc2783563651 (unknown [9.145.72.200]) by d06av24.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 27 May 2019 12:03:19 +0000 (GMT) Date: Mon, 27 May 2019 14:03:17 +0200 From: Halil Pasic To: Cornelia Huck Cc: Michael Mueller , KVM Mailing List , Linux-S390 Mailing List , Sebastian Ott , Heiko Carstens , virtualization@lists.linux-foundation.org, "Michael S . Tsirkin" , Christoph Hellwig , Thomas Huth , Christian Borntraeger , Viktor Mihajlovski , Vasily Gorbik , Janosch Frank , Claudio Imbrenda , Farhan Ali , Eric Farman , Pierre Morel Subject: Re: [PATCH v2 5/8] virtio/s390: use cacheline aligned airq bit vectors In-Reply-To: <20190527125531.20038f59.cohuck@redhat.com> References: <20190523162209.9543-1-mimu@linux.ibm.com> <20190523162209.9543-6-mimu@linux.ibm.com> <20190527125531.20038f59.cohuck@redhat.com> Organization: IBM X-Mailer: Claws Mail 3.11.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 x-cbid: 19052712-0012-0000-0000-0000031FE4AD X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 19052712-0013-0000-0000-00002158A819 Message-Id: <20190527140317.5953850d.pasic@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2019-05-27_07:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 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-1905270085 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org On Mon, 27 May 2019 12:55:31 +0200 Cornelia Huck wrote: > On Thu, 23 May 2019 18:22:06 +0200 > Michael Mueller wrote: > > > From: Halil Pasic > > > > The flag AIRQ_IV_CACHELINE was recently added to airq_iv_create(). Let > > us use it! We actually wanted the vector to span a cacheline all along. > > > > Signed-off-by: Halil Pasic > > --- > > drivers/s390/virtio/virtio_ccw.c | 3 ++- > > 1 file changed, 2 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c > > index f995798bb025..1da7430f94c8 100644 > > --- a/drivers/s390/virtio/virtio_ccw.c > > +++ b/drivers/s390/virtio/virtio_ccw.c > > @@ -216,7 +216,8 @@ static struct airq_info *new_airq_info(void) > > if (!info) > > return NULL; > > rwlock_init(&info->lock); > > - info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR); > > + info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR > > + | AIRQ_IV_CACHELINE); > > if (!info->aiv) { > > kfree(info); > > return NULL; > > This patch looks to be independent of the previous patches? > It ain't a clear cut. It could have been a part of the series that introduced AIRQ_IV_CACHELINE. OTOH I'm not sure it buys us anything without patch 4. (I'm no expert on slab allocator so I can't tell much about the probability of getting chacheline aligned memory if we ask for a chacheline sized chunk of memory from kmalloc()). Regards, Halil