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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?w2H4+U3ZAXPfCJrKpaAjiUTYuBxwgNhV0OzsFiQPX7fKeysdvl4umwz3WTIR?= =?us-ascii?Q?kO7zFG1QwzHIBrEUVcu9m3DSLsBol923f7yExcfjpjNg7Kq8L33jhHec5but?= =?us-ascii?Q?VpW3Xq+yHo6/GplEiS2mibnGpmhgMYZMgwk5ycKJutrhhzr2Z60GsygpGXNj?= =?us-ascii?Q?cwkbxKYyH6LaHyBbs1aTX0zfQg3vpjQc2QbiZ0ULIW5Em55IZcXHWcJGFor5?= =?us-ascii?Q?76yRWCo8G4jPVDeNn/t0jhEVZhPfzcs7RnFOF8Z04+2lw8/qvzOb8dtio2fJ?= =?us-ascii?Q?lqfA4PLA9Tp8xwq1hh8EljooeQ+x7qaE2kDFS6jWJKFBNZkWWUEklQsqSAPH?= =?us-ascii?Q?nT56maIM88ZGfKXVtwPyF3OH6fwo4Wo3bNGIDAnxPh7r3uUc6Lxihf5inYYn?= =?us-ascii?Q?4r8/E2Ya081MKv3dl8aznX2FHVjYQfIvMH/tXyvR/i9PvAwhGKYmM/P0geoa?= =?us-ascii?Q?95pb2utEXsebQ2yFwirE0vG5tIu9XgGy2maGQYHa8B3F9JQ7zTy0QkgkCS0s?= =?us-ascii?Q?cgu9xnLea3oMQrCWoPDBy4/aswAB3SnCOBb4N1e/qoELcC1ZCeRyWnRMOLRg?= =?us-ascii?Q?GIYCxAnQZf4FlzaKJsRaPaVF3mHiOrtoktlCVB8WcQ+bTpB7dHUhJhNd3ULw?= =?us-ascii?Q?GN153s5KHJ7OhgmSVPQ9p7xWLOzYBhrbvL68DHfspYW+dL4LUsk/TuVStWVS?= =?us-ascii?Q?GZvWeBSk4Ae5P9+v77jjSlcPLLFowoxvDnPb+vbUdRKtsGlQPsUwzLrxc95y?= =?us-ascii?Q?oxb7qT6fgvbs5qUJEpdzbHCnvvXN8GBM8BW2IxiwgUcbgcNKPN1Ijof6vF6W?= =?us-ascii?Q?wk5a6tnBmqgmPUBNUhOpkwj2RVsvNZgj78rryuf/2562G0FTe8qRx3/PmmOE?= =?us-ascii?Q?/UJnTUvta9Wv8F+fLFvN/JldaXyEpggw+T0mwK+pTfgGk3Pi2RVk73ZOMySR?= =?us-ascii?Q?p8AacTTX/R9a4YtrCWkn4fBWNYy6IQ2kS9747ODoGvfkSNppOj2SlKFgO8XA?= =?us-ascii?Q?dzzGSo4UNapVrBGckXrsbGPHBo7Hv2Min4HZn+Xj/x9aRrfyrimAEVEKvPez?= =?us-ascii?Q?QBLnD7sh1+RG9HY43cpMWMKSK6Ot+A9Yk+Xs80Bs0ECGFDNmPlQPzJ7vxo2E?= =?us-ascii?Q?3nZKMBWBxffQ4yzRzuiRkzbJCoAx6j6HakQkLQ7xRq+N0wVSUFxt8l/R+0+I?= =?us-ascii?Q?yPmdrI6o33JFXc+mNBF1RQxHRTSJ4XzHuBPYKFTKYnl5wfONYvQ++pq/hFvd?= =?us-ascii?Q?3+wSS/WbD2KBo/i63eT4Lj3P06GnJakH8AxvHVgJeshqvy0RDaNgPaeGrPeI?= =?us-ascii?Q?3lrVEcbRkj09aSL2pii7K9T4v5/MR+r7GRrk8U8Xwa38QYHRDe8ke/8BT2CT?= =?us-ascii?Q?ohTzFUKP9OUrt7vJJoGZd6ROuxyc7Bn6Chl96aMngXbE1s5FDczfAKs9YzsN?= =?us-ascii?Q?5dXa7LyGO01LAMspjT8JyvboyAbywJSFS94eS1HxXl1FquM3jzDdMa6OdWNv?= =?us-ascii?Q?8SFJBor/PSlIE6Fwc7TdRRFlazGy2p/u/2CwsiNvpWlwhJDUCmGNp6L6SVtQ?= =?us-ascii?Q?vNYroua+CqHxs6TExG3TrVH7a1OHKXCbCfzj8lj/oeYiVNxhb6dt4yPeUt7M?= =?us-ascii?Q?0L5Dx5dCgErg+I1Rr7Bb4AWLu+3H75/mkHEPBoiljVuvy+n8qpZImuOYveJz?= =?us-ascii?Q?2ks1/oUzh/Uc/Ybig3wCUktS3a1KQF1HvcFQTXCbRY/i17+gRpTDFeXACe4q?= =?us-ascii?Q?l3kN2lpdtQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 868ae82d-7d9e-435c-145b-08de9e462b47 X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Apr 2026 19:02:14.6844 (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: tqCEwEfhi6dnV/fAZcZHzlrE95NM1LeDSjCShdLicZP+xNHKnm5AcowOpsxNOCIIdXXPKj+E2hBmawfeqGpSug== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA0PPF80FB91A80 On Sun, Apr 19, 2026 at 08:36:45AM -1000, Tejun Heo wrote: ... > +static void scx_tid_hash_insert(struct task_struct *p) > +{ > + int ret; > + > + lockdep_assert_held(&scx_tasks_lock); > + > + ret = rhashtable_lookup_insert_fast(&scx_tid_hash, > + &p->scx.tid_hash_node, > + scx_tid_hash_params); > + WARN_ON_ONCE(ret); > +} Hm... WARN_ON_ONCE() only fires once, it can be hard to catch subsequent errors, especially in case of -ENOMEM. How about triggering WARN_ON_ONCE(ret == -EEXIST), which should be considered a real sched_ext core bug, and use scx_error() for insert failures (ENOMEM). In this way the error is more obvious for the BPF scheduler and can immediately exit if it happens (even if scx_error() is probably a bit of a semantic stretch in this case)? Thanks, -Andrea