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Message-ID: References: <20220623085858.42945-1-thomas.liu@ucloud.cn> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: X-Originating-IP: [10.126.230.35] X-ClientProxiedBy: rnnvmail203.nvidia.com (10.129.68.9) To rnnvmail201.nvidia.com (10.129.68.8) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: a144b870-f1d6-4853-c376-08da581b182a X-MS-TrafficTypeDiagnostic: DM6PR12MB2843:EE_ X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:12.22.5.236;CTRY:US;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:mail.nvidia.com;PTR:InfoNoRecords;CAT:NONE;SFS:(13230016)(4636009)(7916004)(136003)(39860400002)(376002)(346002)(396003)(40470700004)(36840700001)(46966006)(54906003)(107886003)(8676002)(5660300002)(36860700001)(4326008)(316002)(336012)(186003)(6916009)(16526019)(47076005)(9686003)(426003)(82310400005)(40480700001)(70586007)(83380400001)(26005)(70206006)(81166007)(41300700001)(2906002)(33716001)(478600001)(356005)(40460700003)(8936002)(82740400003)(86362001)(36900700001)(67856001);DIR:OUT;SFP:1101; X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Jun 2022 08:57:41.7444 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: a144b870-f1d6-4853-c376-08da581b182a X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=43083d15-7273-40c1-b7db-39efd9ccc17a;Ip=[12.22.5.236];Helo=[mail.nvidia.com] X-MS-Exchange-CrossTenant-AuthSource: BN8NAM11FT061.eop-nam11.prod.protection.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB2843 Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Jun 27, 2022 at 04:45:14PM +0800, Tao Liu wrote: > On Mon, Jun 27, 2022 at 10:42:02AM +0300, Leon Romanovsky wrote: > > On Thu, Jun 23, 2022 at 04:58:58PM +0800, Tao Liu wrote: > > > We hit a divide 0 error in ofed 5.1.2.3.7.1. But dim.c and > > > rdma_dim.c seem same as upstream. <...> > > > Fixes: f4915455dcf0 ("linux/dim: Implement RDMA adaptive moderation (DIM)") > > > Signed-off-by: Tao Liu > > > --- > > > lib/dim/rdma_dim.c | 3 +++ > > > 1 file changed, 3 insertions(+) > > > > I think that this change will be better as it won't change > > decision order in rdma_dim_stats_compare() > > > > diff --git a/include/linux/dim.h b/include/linux/dim.h > > index b698266d0035..69ae238ec2dc 100644 > > --- a/include/linux/dim.h > > +++ b/include/linux/dim.h > > @@ -21,7 +21,7 @@ > > * We consider 10% difference as significant. > > */ > > #define IS_SIGNIFICANT_DIFF(val, ref) \ > > - (((100UL * abs((val) - (ref))) / (ref)) > 10) > > + (ref && (((100UL * abs((val) - (ref))) / (ref)) > 10)) > > > > /* > > * Calculate the gap between two values. > > > > > Reviewed code in net_dim_stats_compare() and rdma_dim_stats_compare(), the > crash point is the only place not covered 0 condition. So it maybe not > need to change the macro. Change in the macro ensures that we check cqe_ratio only when it is needed. Can you please resubmit? Thanks > > But I am not familiar with the algorithm, and not sure what is the right > return value. > > > > > > diff --git a/lib/dim/rdma_dim.c b/lib/dim/rdma_dim.c > > > index 15462d54758d..a657b106343c 100644 > > > --- a/lib/dim/rdma_dim.c > > > +++ b/lib/dim/rdma_dim.c > > > @@ -34,6 +34,9 @@ static int rdma_dim_stats_compare(struct dim_stats *curr, > > > return (curr->cpms > prev->cpms) ? DIM_STATS_BETTER : > > > DIM_STATS_WORSE; > > > > > > + if (!prev->cpe_ratio) > > > + return DIM_STATS_SAME; > > > + > > > if (IS_SIGNIFICANT_DIFF(curr->cpe_ratio, prev->cpe_ratio)) > > > return (curr->cpe_ratio > prev->cpe_ratio) ? DIM_STATS_BETTER : > > > DIM_STATS_WORSE; > > > -- > > > 2.30.1 (Apple Git-130) > > > > >