diff --git a/tools/sched_ext/scx_flatcg.bpf.c b/tools/sched_ext/scx_flatcg.bpf.c
index fec359581826..0fd214cc61da 100644
--- a/tools/sched_ext/scx_flatcg.bpf.c
+++ b/tools/sched_ext/scx_flatcg.bpf.c
@@ -256,7 +256,7 @@ static void cgrp_cap_budget(struct cgv_node *cgv_node, struct fcg_cgrp_ctx *cgc)
 	 * and thus can't be updated and repositioned. Instead, we collect the
 	 * vtime deltas separately and apply it asynchronously here.
 	 */
-	delta = __sync_fetch_and_sub(&cgc->cvtime_delta, cgc->cvtime_delta);
+	delta = __sync_fetch_and_and(&cgc->cvtime_delta, 0);
 	cvtime = cgv_node->cvtime + delta;
 
 	/*
@@ -570,7 +570,8 @@ void BPF_STRUCT_OPS(fcg_stopping, struct task_struct *p, bool runnable)
 	cgc = find_cgrp_ctx(cgrp);
 	if (cgc) {
 		__sync_fetch_and_add(&cgc->cvtime_delta,
-				     p->se.sum_exec_runtime - taskc->bypassed_at);
+				     (p->se.sum_exec_runtime - taskc->bypassed_at) *
+				     FCG_HWEIGHT_ONE / (cgc->hweight ?: 1));
 		taskc->bypassed_at = 0;
 	}
 	bpf_cgroup_release(cgrp);