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, 40 insertions, 0 deletions

diff --git a/rust/helpers/time.c b/rust/helpers/time.c
new file mode 100644
index 000000000..32f495970
--- /dev/null
+++ b/rust/helpers/time.c
@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/delay.h>
+#include <linux/ktime.h>
+#include <linux/timekeeping.h>
+
+__rust_helper void rust_helper_fsleep(unsigned long usecs)
+{
+	fsleep(usecs);
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_real(void)
+{
+	return ktime_get_real();
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_boottime(void)
+{
+	return ktime_get_boottime();
+}
+
+__rust_helper ktime_t rust_helper_ktime_get_clocktai(void)
+{
+	return ktime_get_clocktai();
+}
+
+__rust_helper s64 rust_helper_ktime_to_us(const ktime_t kt)
+{
+	return ktime_to_us(kt);
+}
+
+__rust_helper s64 rust_helper_ktime_to_ms(const ktime_t kt)
+{
+	return ktime_to_ms(kt);
+}
+
+__rust_helper void rust_helper_udelay(unsigned long usec)
+{
+	udelay(usec);
+}