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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?161Tmls1FjUf/BxjQC6oQkFY7MeZQwjWgHh2dFgw4G0i/FFtfKn46/Aykejn?= =?us-ascii?Q?SQz8iSyuo3rNVw4vSwkKIW9DOvYN0CRFuNWa2zc0A/E3y2Z5Up/ik978bRR0?= =?us-ascii?Q?8wPGKjxpjevxfnGh24tUTt27GntOIipBecvJafx2Km0Nu+buggw7bvN0kVz4?= =?us-ascii?Q?a+f13uugk0WPOg/WTRYJPSxl8jmFLlyjdGsQnU2hIqnt7Z+202aO5SwmCOYs?= =?us-ascii?Q?nBe2mlBzjjkXE1nC9sPdYxVwvo+V+TffDkQwZSMiEOFh6K5G5aJqI1FFwC+Z?= =?us-ascii?Q?JdW7D3TXMkyFT8mzIpF68DXhHe7im6FscCJBdJOzpWtVR0Pi5F0VDfuiZsRY?= =?us-ascii?Q?dkc42E0Pm6qn2XuRJBTYJRzCUj4wJegs0CSZO8Gdn24dbUSBPLwwsy7RAewf?= =?us-ascii?Q?goh1nGlZkVreIlwoS/Tl2VH6xh2cbrtGHC/aHEDmwTvTqXv3GOvgptU4d9JM?= =?us-ascii?Q?hzw3ud87FNsde5VNXAFAcdpESSSGFyfJ6LnWLW/j1uIpIX8q2QrugtAGBf98?= =?us-ascii?Q?NlE/BiQymGCCnh9ptvkr2iVjym0T4tAV5UkTNJUg0GrAxlvBlpoLduz9nuao?= =?us-ascii?Q?VX/y2xNANstrI9EUU9ie45SuUpwYJdhdesola2CZ2vaDUb5JPofBCJPYpskO?= =?us-ascii?Q?4GbEHbTmGnbkb2YPlone1SkT+1QxhB09hUD7ELkBu4YFEgeR5MLObyuOWMoQ?= =?us-ascii?Q?fvxUUHk6f3ii/fNbG95s2WXvxkst43cRPzEG4pKuKUrKUzKlQWhFYnD7NpUY?= =?us-ascii?Q?LWUMW8Xh1uqwoPqLv6cDwAZtgeJJ4TeRIUFY6pkVSGytRWxbIrHmmKV7WG9R?= =?us-ascii?Q?VdgYD4Tmf1W4QXxKqZiOjKtjQY4wbrZbTDBM8xLb/B1DDhLrrSpkNmlQeV0S?= =?us-ascii?Q?w5Mq+KZvwtCXIYelKJKlW9pfS5rLpy4bI4LvVKtkeYqIuOksxoBV3jm62YiW?= =?us-ascii?Q?rhjCD08JcTbKz22GEyuBib7gAcjAjrovjN2ilwHoPKXdRJXxiiSPWTi7XnA4?= =?us-ascii?Q?kSSjzxbEclOXROADaK/he8wCRv1/mmIyOk5KBcLQMd+adGVWDp8KtQdI0sn+?= =?us-ascii?Q?iYeNhthSfjiPscE7VNO3mS9fdbQx2ziqylipoV+QC7MGvCc7kDkukH3Vc0Dx?= =?us-ascii?Q?250iSEcVs4Fc9S9+jhIIbJ4DwEcYxTw4GTb0f0X9ubFa57QDqcK4JwVfiOk0?= =?us-ascii?Q?0SsqDcYvdLW+87MUXnlT8jHGaxJ6ZAyLwME5RBB50whPmrVMkW0Y878w5eYi?= =?us-ascii?Q?VU5qcsG8UtVH42A43NFkLbyf8+CABdADXoX+IqxNTLbAlPjQizQt2rx59Hqd?= =?us-ascii?Q?j5uAjIx/ya082EYtOc9XX3SiSHd//j42zJlojdF42Iw+MGNbqFDv/ndaZCzv?= =?us-ascii?Q?e9YFSUiDVAGdhWNktFgweOo6NcV1R2FtVhFvFffwho656ECTKLl2LiNoBbZc?= =?us-ascii?Q?xV8H/rxv5078QMCGyVgJyorGzaV8gVAO4DnoNw0/2//pM1wT5fsNBmfaXNe4?= =?us-ascii?Q?E7VtSa9efNGItIOSEuu7iTENYhtPM7Kj5WlFwIUZt+Mc6ZkjyLRWP4hjaO76?= =?us-ascii?Q?BG53bpFT46ceA+hKOjh+QoTHCP7RBXBZso0UEjZX?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 50683444-7a3c-44fa-5eab-08dd435409b5 X-MS-Exchange-CrossTenant-AuthSource: CY5PR12MB6405.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 02 Feb 2025 06:37:18.1213 (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: 3CH2p+PvtXF4WsSK6fAT2B+W9iOvUdqsmLZZtDsF+zJh9A2+UxULwJJofyWCX3SMC25R1iziHdFzYe1kO/ivRg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: MW4PR12MB6707 On Sun, Feb 02, 2025 at 12:37:48PM +0900, Changwoo Min wrote: > When (s64)(after - before) > 0, the code returns the result of > (s64)(after - before) > 0 while the intended result should be > (s64)(after - before). That happens because the middle operand of > the ternary operator was omitted incorrectly, returning the result of > (s64)(after - before) > 0. Thus, add the middle operand > -- (s64)(after - before) -- to return the corRECT time calculation. > > Fixes: d07be814fc71 ("sched_ext: Add time helpers for BPF schedulers") > Signed-off-by: Changwoo Min > --- > tools/sched_ext/include/scx/common.bpf.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/tools/sched_ext/include/scx/common.bpf.h b/tools/sched_ext/include/scx/common.bpf.h > index f254a39b86a5..d72b60a0c582 100644 > --- a/tools/sched_ext/include/scx/common.bpf.h > +++ b/tools/sched_ext/include/scx/common.bpf.h > @@ -432,7 +432,7 @@ void bpf_rcu_read_unlock(void) __ksym; > */ > static inline s64 time_delta(u64 after, u64 before) > { > - return (s64)(after - before) > 0 ? : 0; > + return (s64)(after - before) > 0 ? (s64)(after - before) : 0; Ugh.. how did we miss this? Thanks for noticing. Acked-by: Andrea Righi -Andrea