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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?4X3dVv1tSUoD20dFPwQoUEkgR5mNmmQDM3oe5HonoUvMDnN66LCGsfPMl0R1?= =?us-ascii?Q?b3wHT9UXGNEBLs2Fbip16udVt0GmoJGkGoQWJuy1Y0ifLVMB5foSc6aczGq/?= =?us-ascii?Q?AHpPyTAPxq+VSGXKkmnWq/nKEOq3cte3XtFanuiFE34SlNR6egO4SWdY5zN0?= =?us-ascii?Q?qWMMZRRu6R1xgm0NkprwvC7BVAGERK+vK58WZ4K8WyPFNhsovFAQNFdqymdT?= =?us-ascii?Q?D4i0qpLnrrrnzaTW0sEb1USwvNeVr95iZzlk/RCEnOqILddxdW+cRVeRgCTK?= =?us-ascii?Q?pRbol1NONIoMlyv9wWj9sy6LwrKjNzynaaFkjphHngCxACDZemVmjWX6qqe5?= =?us-ascii?Q?VXoHt/F5w057nJ0CLd/8zJ9dRI5piOom3bqzeUVk4IxVxzJ+YklKQ+8PxdHN?= =?us-ascii?Q?uL88Sd+PICDrxZq4dOOdJJKnmJwSXsa+hE9a84NhfCcLFGHlRu3nONgJCwfo?= =?us-ascii?Q?s/RGs80x0wKeCmcVzwMf6r5LDkCmgj/s386iy4mTPEjw7snbAp87rYdzgfZ/?= =?us-ascii?Q?1AtGZaHtNUjG8sgpSXXuCOMinQmbyAKMK+n+dd11hhpYimEghu9DHclcIj6y?= =?us-ascii?Q?6CnzEG1ww+TT74lvj8bJGSLlfeOj9QUPzzFB5sjaoAQFEO//NIHH/Djas5QH?= =?us-ascii?Q?dzQfeW9FhRrMWM6JqFo4hFMjKO8oIGN4oIpg7B/ptN54RUoyj38mrSJq7KFJ?= =?us-ascii?Q?bgn4dR7p3tyi/BNI8bC5mVeotifJVwjo1+MeYMRT+qRkFdYqfEWHcXBUE9/6?= =?us-ascii?Q?YM5bZeUc961dFXOJkSuwD+qfMpc16zKmRml+4zUbHznfv87hsaPEu2WTAxh0?= =?us-ascii?Q?Azmi6819nDDt0GxcLN4AiRB62fhfsRWgP4E5OpOJgBcN7bghC1nVfNj2u58i?= =?us-ascii?Q?W/HvjM71KuUwiTeambOMERCAN+DWVc/kCJuMrIkCf/Cl4TCvbnsf4W+f8q2r?= =?us-ascii?Q?X33ylZurWRX6ewhusDInC2zDeBQdvAgjql0dKnPHlEdFN/u31WXSmx4BQRLP?= =?us-ascii?Q?/FgeEGA1Wh2N29TUcHFELgff0RId6syLMANN+qK6aUcxmu2j6beoghEgDIu2?= =?us-ascii?Q?/kralIU8E8RPG4+YARbyoB0Y9dPejXAaPTgYxaZ4U5j4esPXs6iLd6jX1p2+?= =?us-ascii?Q?pcRJ09ahUKnI+q+x0k9oybdfevqw/tM0jrlb2e61utUhTDdvSAbp5urcwFi2?= =?us-ascii?Q?w0iuDFltfz1Shi3dPyaUnIEqpRnhbqfNqN1gQd177xl7aPbgHC1Ty5OE+4H9?= =?us-ascii?Q?yolYXCxbXUM9iuXvBXCalZqLgfRNNWurZZj84ukRh7ePLAi4shJwicvZFJ17?= =?us-ascii?Q?h3tL95q0ieY4SXHq5fVJ32JbMMpsctAqiql6GxKjSnNSN6JjKJoqI0Z5Qkzf?= =?us-ascii?Q?/MS+F2e8oiDrrzIcFoWRsctsSKfi7CI6l1e7XvQbiUvh38+W8TLf5J9TepE9?= =?us-ascii?Q?M9+khbYb6L7zW//34g7BBNEcpxQ2CRkgu8nPnFvd2pTZyPq9FOV2vQvTwRiO?= =?us-ascii?Q?fFI5YGMVxAljvSF34EzVgMX8LqkoYUX9KSwb0aJdQrlZ/V2cD+uw0S62Ojbs?= =?us-ascii?Q?QcbGuzL7TbluXyoHJIQ0HbqGDjFdvsVwxCVbq7Q1?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 92033ac6-5daf-419d-0114-08dcfdfaac1d X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Nov 2024 00:33:45.1868 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: dvLFZAzmEc+KiewtLiUazsu1kMXv9LJ1t0Xeb28FqmT8iaBarK51sfMKHe7LXNz7M1LYTHeFZlPah0Ll+6KReg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BL3PR12MB6377 On Tue, Nov 05, 2024 at 02:26:38PM -1000, Tejun Heo wrote: > External email: Use caution opening links or attachments > > > Hello, > > On Wed, Nov 06, 2024 at 12:57:42AM +0100, Andrea Righi wrote: > ... > > Do you think there's any benefit using the idle injection framework here > > instead of this cpu_relax() loop? At the end we're trying to throttle > > the scx scheduler from hammering a DSQ until the scheduler is kicked > > out, so we may just inject real idle cycles? > > That involves switching to the dedicated task and so on, right? When this is > needed, we can't even trust whether the system is going to make forward > progress within the scheduler. I don't think it'd be a good idea to call out > to something more complicated. Also, from forward-progress-guaranteeing > point of view, cpu_relax() is as good as anything else and this shouldn't be > active long enough for power consumption to be a factor. Ok, I see, we want to keep it simple, because the CPUs might be congested (like even from a hardware perspective), so in that case cpu_relax() makes more sense probably. Thanks, -Andrea