From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1164555AbeCBDTQ (ORCPT ); Thu, 1 Mar 2018 22:19:16 -0500 Received: from userp2120.oracle.com ([156.151.31.85]:55936 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1163203AbeCBDTP (ORCPT ); Thu, 1 Mar 2018 22:19:15 -0500 Subject: Re: [PATCH V2] nvme-pci: assign separate irq vectors for adminq and ioq0 To: Christoph Hellwig Cc: axboe@fb.com, sagi@grimberg.me, linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, keith.busch@intel.com References: <1519832921-13915-1-git-send-email-jianchao.w.wang@oracle.com> <20180228164726.GB16536@lst.de> From: "jianchao.wang" Message-ID: Date: Fri, 2 Mar 2018 11:18:47 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 MIME-Version: 1.0 In-Reply-To: <20180228164726.GB16536@lst.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8819 signatures=668682 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=937 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1803020034 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Christoph Thanks for your kindly response and directive On 03/01/2018 12:47 AM, Christoph Hellwig wrote: > Note that we originally allocates irqs this way, and Keith changed > it a while ago for good reasons. So I'd really like to see good > reasons for moving away from this, and some heuristics to figure > out which way to use. E.g. if the device supports more irqs than > I/O queues your scheme might always be fine. maybe we could add a logic that when get enough irq vectors, assign separate irq vector to adminq, otherwise sharing. Sincerely Jianchao From mboxrd@z Thu Jan 1 00:00:00 1970 From: jianchao.w.wang@oracle.com (jianchao.wang) Date: Fri, 2 Mar 2018 11:18:47 +0800 Subject: [PATCH V2] nvme-pci: assign separate irq vectors for adminq and ioq0 In-Reply-To: <20180228164726.GB16536@lst.de> References: <1519832921-13915-1-git-send-email-jianchao.w.wang@oracle.com> <20180228164726.GB16536@lst.de> Message-ID: Hi Christoph Thanks for your kindly response and directive On 03/01/2018 12:47 AM, Christoph Hellwig wrote: > Note that we originally allocates irqs this way, and Keith changed > it a while ago for good reasons. So I'd really like to see good > reasons for moving away from this, and some heuristics to figure > out which way to use. E.g. if the device supports more irqs than > I/O queues your scheme might always be fine. maybe we could add a logic that when get enough irq vectors, assign separate irq vector to adminq, otherwise sharing. Sincerely Jianchao