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, 19 insertions, 0 deletions

diff --git a/drivers/acpi/debugfs.c b/drivers/acpi/debugfs.c
new file mode 100644
index 000000000..074eb98d2
--- /dev/null
+++ b/drivers/acpi/debugfs.c
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * debugfs.c - ACPI debugfs interface to userspace.
+ */
+
+#include <linux/export.h>
+#include <linux/init.h>
+#include <linux/debugfs.h>
+#include <linux/acpi.h>
+
+#include "internal.h"
+
+struct dentry *acpi_debugfs_dir;
+EXPORT_SYMBOL_GPL(acpi_debugfs_dir);
+
+void __init acpi_debugfs_init(void)
+{
+	acpi_debugfs_dir = debugfs_create_dir("acpi", NULL);
+}