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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 E8FEEC56201 for ; Thu, 12 Nov 2020 11:20:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 974E122246 for ; Thu, 12 Nov 2020 11:20:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727865AbgKLLUX convert rfc822-to-8bit (ORCPT ); Thu, 12 Nov 2020 06:20:23 -0500 Received: from szxga01-in.huawei.com ([45.249.212.187]:4094 "EHLO szxga01-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727920AbgKLLUP (ORCPT ); Thu, 12 Nov 2020 06:20:15 -0500 Received: from DGGEMM404-HUB.china.huawei.com (unknown [172.30.72.57]) by szxga01-in.huawei.com (SkyGuard) with ESMTP id 4CWzfF46gPzXlrk; Thu, 12 Nov 2020 19:20:05 +0800 (CST) Received: from dggema751-chm.china.huawei.com (10.1.198.193) by DGGEMM404-HUB.china.huawei.com (10.3.20.212) with Microsoft SMTP Server (TLS) id 14.3.487.0; Thu, 12 Nov 2020 19:20:12 +0800 Received: from dggema753-chm.china.huawei.com (10.1.198.195) by dggema751-chm.china.huawei.com (10.1.198.193) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1913.5; Thu, 12 Nov 2020 19:20:12 +0800 Received: from dggema753-chm.china.huawei.com ([10.9.48.84]) by dggema753-chm.china.huawei.com ([10.9.48.84]) with mapi id 15.01.1913.007; Thu, 12 Nov 2020 19:20:12 +0800 From: liweihang To: Jason Gunthorpe CC: "dledford@redhat.com" , "leon@kernel.org" , "linux-rdma@vger.kernel.org" , Linuxarm Subject: Re: [PATCH for-next] RDMA/hns: Create QP/CQ with selected QPN/CQN for bank load balance Thread-Topic: [PATCH for-next] RDMA/hns: Create QP/CQ with selected QPN/CQN for bank load balance Thread-Index: AQHWjceX3aRvAeQKjEuzXmMmmBepcA== Date: Thu, 12 Nov 2020 11:20:12 +0000 Message-ID: <4199dbabf478450fa4e2e6aec6b7b776@huawei.com> References: <1599642563-10264-1-git-send-email-liweihang@huawei.com> <20200918142525.GA306144@nvidia.com> <115588ae632747f29e977f6abf0a5733@huawei.com> <20201106133707.GV2620339@nvidia.com> <20201110174615.GQ2620339@nvidia.com> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.67.100.165] Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On 2020/11/11 1:46, Jason Gunthorpe wrote: > On Tue, Nov 10, 2020 at 09:19:39AM +0000, liweihang wrote: >> On 2020/11/6 21:37, Jason Gunthorpe wrote: >>> On Fri, Nov 06, 2020 at 01:52:57AM +0000, liweihang wrote: >>> >>>> There are 8 banks and each of them has a counter which represents >>>> how many QPs are using this bank. We first find the bank with the >>>> smallest count, and then try to find a QPN belongs to this bank >>>> according to the bitmap. The ida will find an unused ID starting >>>> from 0, I think it can't meet our needs. If we use ida here, the >>>> code may looks like: >>> >>> I don't understand, why wouldn't the ida give you a free QPN in a bank >>> directly? >>> >>> Jason >>> >> >> Hi Jason, >> >> Here is the QPN that belongs to each bank: >> >> QPN on bank0：0, 8, 16, 24 ... >> QPN on bank1: 1, 9, 17, 25 ... >> QPN on bank2: 2, 10, 18, 26 ... >> ... >> QPN on bank6: 6, 14, 22, 30 ... >> QPN on bank7: 7, 15, 23, 31 ... >> >> If bank 6 is the one with the lowest load, then we need to find a >> valid QPN belongs to bank6, that means, the lower 3 bits of QPN is >> 6 and it hasn't been used. >> We can't find out a way to use ida in this situation because the >> QPNs of each bank are discontinuous. > > Each bank has an IDA, you allocate from the IDA then shift left and or > in the bank number > > Jason > Thanks for your advice, we will achieve it and do some tests. Weihang