From 029b6ce733712a41421955194b113f283dcb1026 Mon Sep 17 00:00:00 2001 From: Changwoo Min Date: Sun, 2 Feb 2025 12:37:48 +0900 Subject: [PATCH] sched_ext: Fix incorrect time delta calculation in time_delta() 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 Acked-by: Andrea Righi Signed-off-by: Tejun Heo --- 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; } /** -- 2.50.1