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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?ux4H8R/lmVIpjj85DXJ4XmxXlaycxrP24gX/wW7gNjyexmVCCA2YBCS3IZxT?= =?us-ascii?Q?6H72U/7RLPsrk0Lhusc0sSdtgw7o2Bvy7CXplZtMAHbiR1r7lr+56Y3y6ZkO?= =?us-ascii?Q?Ndce3N9IVigre4Hx8JnxNJmGDenlEdJifgZzsy8wQHvPJnNjWIpbIT+ehc9T?= =?us-ascii?Q?MZrJx2tNigHSdHzbwRA4diHbsi4hb7lXSAH92cHNfK4GGNbrr9zlU5gzLG2e?= =?us-ascii?Q?dnHIPOKuX88Rus6dEo00JfSq0Ql4nJ8sOOWmv/rRQlG2T3TewQ+3yOHY4PhS?= =?us-ascii?Q?5J41mIL8q0NH9hhg6aEAdvUBNv0Parx6i/cqneBtP4bO9zn8HRMVGN/Dwal6?= =?us-ascii?Q?jBcvj0fjr2d0T9FAhakeIAKujUXS7S6qRTsOfzI4/GrZimv40OOXTEfx5dnR?= =?us-ascii?Q?jgQooXgniOvccPfXExB0zL0aGCMQqIuXcx9dLK4sRlvbY9aSBM3ZDjigxx2e?= =?us-ascii?Q?K8gp5gix4eZw1PsKK5G9ab5eKysXLwO9qUvl7uFmlh7+JZb4Mm3VP4QcriXn?= =?us-ascii?Q?zVEaLJQrN0Q6bd7paYLkeURqj7gn1Y6QacB7snb/ilPHYdPjAqcwbG8SXytI?= =?us-ascii?Q?xeOW/pzb5IzPGhbtZw2Sf5J5pOP6sarSK9TKdZ4D9iESF/JokzWx2n1T6iyt?= =?us-ascii?Q?VqVIoYvjUpNYNquiAxF1yu52Ea7/c4W/Y7Na5+2qtHyjH7xi5XBgK0uwevMY?= =?us-ascii?Q?10/1ig0y+3qo3ds9Ai/ihCTnsUm+yIABNoogFaMH8adKm9k+JKFdM8kWAtl7?= =?us-ascii?Q?WRoJOG/v9MODP/VZ/8Wsc1n7PMD/tFlEXxeXkTowXCc9G0vRGfXaULNAmgrD?= =?us-ascii?Q?NOJizGVK3JwdC8Cao9HEoKHbkX7WbwYOkDjck+CRA2qJfshrqSoj7UMN669Y?= =?us-ascii?Q?7WMDuK2Ql5Iyt/+qAHsHoGOmW0Ht3lr13KAWYMg/SjRW4r8dnXv5b/6IilMk?= =?us-ascii?Q?FM8zKX5HcspBtuNaI8b8mRn71KBT4iYNcS3KnFAiYxk75VL7g33JA2vkIb5Q?= =?us-ascii?Q?PZHdWntxjoSEDE/A3I7RGqi9SIOi/+ZwdF75TylvGLBELF+3G/uXk3q6y9Xu?= =?us-ascii?Q?hJo2aIXI9/NMMqSAO+5nVBIwNKAOV5HSKG08cnx2tJ8trzI08zVvwDsp4RIp?= =?us-ascii?Q?5gMSPgJnnbw4LwVCpQMvRxxpH1xK1lxh1dR5EGhP6n8oqS2eb7hQt03oC1EZ?= =?us-ascii?Q?dyJt2rvVb/rqIRevSKSbz1nLQ/FfOWnKvy54R7hKFseSwGzDt4K7gS+wW/YO?= =?us-ascii?Q?orOyL4wNHLXyQ9UTcZK1POY/hp17v/jA/q3KJeOjcQI/HNdZXRbgWU8nbm8E?= =?us-ascii?Q?2Q0yVK8Mb4EcqVPnhRsrIp5VBTozXhg/p4l6Cp8r2PVTrO+92UZ42SetzFG2?= =?us-ascii?Q?+rmFCKyLYb57A+q5XYzwLiIj53BKER4MDZ4+aZPnNHQHn8unOVujHi5XgP4n?= =?us-ascii?Q?0+2pSjMn+vsgCzfgEm8PVNXJFKJ+umqIQG4hg5o3FzC2RCbWatYBRFZDxIW2?= =?us-ascii?Q?EhxMTYM6A1lI2+DXNslwKCinqG4DuUfn/mzQ65e8jRjTrDOr3iGegiqKMUxn?= =?us-ascii?Q?axv9WIXzh2TXQilaLG/z5vhjXLQXz/H3UJR8N2tM?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 790c1084-3f01-4048-57bb-08dd5b76f6f7 X-MS-Exchange-CrossTenant-AuthSource: SN7PR12MB8059.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Mar 2025 23:47:46.5275 (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: 04lyb2rppscQgXyWdcbJWLO4KTNDc2UWAMpmm31FEipd+uJEiKqOT36RJviCsyJFCVwkzSSRRU41xdjk+/3L+Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY5PR12MB6598 On Tue, Mar 04, 2025 at 03:06:32PM -0500, Steven Rostedt wrote: > On Tue, 4 Mar 2025 15:01:16 -0500 > Joel Fernandes wrote: > > > Currently, RCU boost testing in rcutorture is broken because it relies on > > having RT throttling disabled. This means the test will always pass (or > > rarely fail). This occurs because recently, RT throttling was replaced > > by DL server which boosts CFS tasks even when rcutorture tried to > > disable throttling (see rcu_torture_disable_rt_throttle()). > > > > Therefore this patch prevents DL server from starting when RC torture > > sets the sysctl_sched_rt_runtime to -1. > > > > With this patch, boosting in TREE09 fails more than 50% of boost attempts > > making the test more useful. > > > > Also add a check of this to task_non_contending() because otherwise it > > throws a warning (in the case when DL server was already started before > > rcutorture started). > > > > Hmm, I wonder if dl_server caused a regression. That is, disabling rt > throttling should allow RT tasks to starve anything it wants. And some RT > applications rely on this. > > Should this include a Fixes and Cc stable? Yeah that makes sense to me, I'll include the Fixes tag in the v2. thanks, - Joel