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, 35 insertions, 0 deletions

diff --git a/rust/helpers/srcu.c b/rust/helpers/srcu.c
new file mode 100644
index 000000000..1a2f56364
--- /dev/null
+++ b/rust/helpers/srcu.c
@@ -0,0 +1,35 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/srcu.h>
+
+__rust_helper int rust_helper_init_srcu_struct_with_key(struct srcu_struct *ssp,
+							const char *name,
+							struct lock_class_key *key)
+{
+	return __init_srcu_struct(ssp, name, key);
+}
+
+__rust_helper bool rust_helper_srcu_readers_active(struct srcu_struct *ssp)
+{
+	return srcu_readers_active(ssp);
+}
+
+__rust_helper int rust_helper_srcu_read_lock(struct srcu_struct *ssp)
+{
+	return srcu_read_lock(ssp);
+}
+
+__rust_helper void rust_helper_srcu_read_unlock(struct srcu_struct *ssp, int idx)
+{
+	srcu_read_unlock(ssp, idx);
+}
+
+__rust_helper void rust_helper_srcu_barrier(struct srcu_struct *ssp)
+{
+	srcu_barrier(ssp);
+}
+
+__rust_helper void rust_helper_synchronize_srcu_expedited(struct srcu_struct *ssp)
+{
+	synchronize_srcu_expedited(ssp);
+}