selftests/bpf: Add a test for objects stuck in free_by_rcu_ttracegrafted

Delete all elements of BPF_F_NO_PREALLOC hash map in one batch. The first
free_bulk() starts RCU tasks trace GP and the rest of the elements are
freed while it's in flight. Wait for call_rcu_ttrace_in_progress to clear
in bpf_mem_cache of every cpu and check that free_by_rcu_ttrace and
waiting_for_gp_ttrace lists are empty.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20260930095920.601738-4-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 31 insertions, 0 deletions

diff --git a/tools/include/nolibc/math.h b/tools/include/nolibc/math.h
new file mode 100644
index 000000000..9df823ddd
--- /dev/null
+++ b/tools/include/nolibc/math.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
+/*
+ * math definitions for NOLIBC
+ * Copyright (C) 2025 Thomas Weißschuh <thomas.weissschuh@linutronix.de>
+ */
+
+/* make sure to include all global symbols */
+#include "nolibc.h"
+
+#ifndef _NOLIBC_SYS_MATH_H
+#define _NOLIBC_SYS_MATH_H
+
+static __inline__
+double fabs(double x)
+{
+	return x >= 0 ? x : -x;
+}
+
+static __inline__
+float fabsf(float x)
+{
+	return x >= 0 ? x : -x;
+}
+
+static __inline__
+long double fabsl(long double x)
+{
+	return x >= 0 ? x : -x;
+}
+
+#endif /* _NOLIBC_SYS_MATH_H */