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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?KvJlEqnVYF1yfhpt9QXZ5ujHNPFRHe7b11TCMoJoTyOWEr9s3zbeRVdemshm?= =?us-ascii?Q?FA19gMO2/5gu4xzCS0LyLKNn01DWnkXxUWbu9HeY5YGFjW2RJgDLS3x+EgTZ?= =?us-ascii?Q?gFYeIZKIfqAWVr7S7FHFRL4Jupj2I+yu26I9VCR8vERkK2U9EW7toQd3U9a1?= =?us-ascii?Q?VLxllDDXLt+UqGM2E+iPktyI9jm1HsyZ5mrUIlqZ6FJ3wpUDwGHHKvNOHzkX?= =?us-ascii?Q?YvfgNbKw8Av3jn7Ri2X8q6c/ubTAZg41OE7y9zEpM3bNMQElDzhmmLH6uccB?= =?us-ascii?Q?/vgaSbN+2cH9jM3xTyrPuaiw+qfpit9wv/eu7CUCT9t3wbnIt/u23T5wlXRY?= =?us-ascii?Q?pcJsL34Xg/RF20XVg8YIC1J648nZ1J1SBvpU/Fnuz7QybjHeTwuflYlNke1N?= =?us-ascii?Q?tp5Ol57LdoTbv/LlI28ipMXCye9r62xp6Vrg7WOY/4M66assdZ6lfiX3RMNA?= =?us-ascii?Q?fmAxlMCo46ap3pIR3ufIGv86OzNFMObQUUQuf6uBtlRREcUYJ0J11Gc5DX36?= =?us-ascii?Q?BduPFRkBZUrAFq0B7K2ULs74xtBm/WvTkQpFbEbq89zGjkHJ9ji3/hD6wfjr?= =?us-ascii?Q?oQl1YRtwunDvcRZa+CPpuSCGwCZze9vV0bg0IQwBNMy5YXzm9bZliz5WyfzM?= =?us-ascii?Q?hawj3rXx6qiUkLeIdpHlkqj0tfOjvOgNndUNKB86xb4BiC/28mYll9q4aKYg?= =?us-ascii?Q?CSi1pYt1xd+oWd+Uql8QQrvEiLNBPGKfupjYnOJ2hfrvpxtmUWfWijOEu+87?= =?us-ascii?Q?eBAIs7WDDhaMhnAewEGERGt9euFTHY1bf4tUFcxrbaoQAkz67IETd1tjUfb4?= =?us-ascii?Q?EkawFdElCQ3qkFFRbOI316K6wUEZJjGyz6vlZ8SyZ31UXsqG+1qj5rnn0sxl?= =?us-ascii?Q?Dxi0JFHuWvB1T+nUa1xQt5DCblmWq0sn3Xr+ThaBRgCU7sD1ay9f54pYJalM?= =?us-ascii?Q?95u/T+Bk9dJ5Fdalt0Ts4nErKJukQxxS0KWG2ib1zwMJKIhGoSscOKGtOd52?= =?us-ascii?Q?HwffFN6lGmVGEBe3xLBd6XKNKo4cHV15Yom6yeUxJW46pzZX89aP5gu9Wmz/?= =?us-ascii?Q?z3IkG9JPEsTr2MbcDsyixNtrjtVs7PkWdlzJd+o5K64rT5HFkRd/qFWw1VMg?= =?us-ascii?Q?gDUr2F+L4Qwe/f3MtoA0mn6+LXZvPdi1sYnxJmny2yerY73ueLuZ1yKo5S4D?= =?us-ascii?Q?wjYrGaDErWMRiU/jSSQC3JS2A4Y2Jwh5tntoEh3X5+M2DxG6bo6gkpqnapmH?= =?us-ascii?Q?G44b8smHx4GK4FjVhsIRPnWSe5ZjoJvpGr6btxU2y2GbXgyNwnfcKRHA3ojq?= =?us-ascii?Q?OUAKS/Lk/3MtdHxct4q2xGlC4qyOuwdgQX9DG/43aPHOd5vp9sO5SAYXPs2s?= =?us-ascii?Q?N/8G9r90fHrvsDOdydNXsTdKWJJSj0qvUeuCYS6xFcnp87F7hBRJGpJzyLDc?= =?us-ascii?Q?ous7wLCsSVATYelldYlJc1TQOXL8aFkdva/eXlVqTL2sn3rScd/1F0o1wJ1b?= =?us-ascii?Q?O9c+BLlQQBgYSLp3FOd/e1lEXr4ngt0MyfnvVZbBGNbhNPf1DQoKaiAChupy?= =?us-ascii?Q?jXjpwkuAVbCbMd8hm/XQPvxg7qFVUerWqvLcoS1r?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 805e3d8c-3338-4f6b-2d9c-08dd47431850 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Feb 2025 06:46:05.3559 (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: hDvX6TlXr4eDjSUbYKKO6KqfXYcXt6eSaCQ408uMeS0giRp847mqAH8eprc+0MFr3kDKJ6esLi8CAZ/0YzamxA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH0PR12MB8529 On Fri, Feb 07, 2025 at 03:40:50PM +0900, Changwoo Min wrote: > This patchset introduces a new event, SCX_EV_ENQ_SLICE_DFL, and updates > two scx schedulers -- scx_qmap and scx_central -- to print out the new > event. > > SCX_EV_ENQ_SLICE_DFL counts how many times the tasks' time slice is set > to the default value (SCX_SLICE_DFL) by the sched_ext core in the enqueue > and pick_next paths. > > Scheduling a task with SCX_SLICE_DFL unintentionally would be a source > of latency spikes because SCX_SLICE_DFL is relatively long (20 msec). > Thus, soaring the SCX_EV_ENQ_SLICE_DFL value would be a sign of BPF > scheduler bugs, causing latency spikes. Looks good to me, thanks! Acked-by: Andrea Righi > > ChangeLog v1 -> v2: > - Instrument the event at select_task_rq_scx() when ops.select_cpu() > is not provided. > > Changwoo Min (2): > sched_ext: Add an event, SCX_EV_ENQ_SLICE_DFL > sched_ext: Print an event, SCX_EV_ENQ_SLICE_DFL, in scx_qmap/central > > kernel/sched/ext.c | 16 +++++++++++++++- > tools/sched_ext/scx_central.bpf.c | 2 ++ > tools/sched_ext/scx_qmap.bpf.c | 2 ++ > 3 files changed, 19 insertions(+), 1 deletion(-) > > -- > 2.48.1 > -Andrea