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, 24 insertions, 0 deletions

diff --git a/tools/testing/nvdimm/watermark.h b/tools/testing/nvdimm/watermark.h
new file mode 100644
index 000000000..43fc4f3e7
--- /dev/null
+++ b/tools/testing/nvdimm/watermark.h
@@ -0,0 +1,24 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright(c) 2018 Intel Corporation. All rights reserved.
+#ifndef _TEST_NVDIMM_WATERMARK_H_
+#define _TEST_NVDIMM_WATERMARK_H_
+int pmem_test(void);
+int libnvdimm_test(void);
+int acpi_nfit_test(void);
+int device_dax_test(void);
+int dax_pmem_test(void);
+int dax_pmem_core_test(void);
+int dax_pmem_compat_test(void);
+
+/*
+ * dummy routine for nfit_test to validate it is linking to the properly
+ * mocked module and not the standard one from the base tree.
+ */
+#define nfit_test_watermark(x)				\
+int x##_test(void)					\
+{							\
+	pr_debug("%s for nfit_test\n", KBUILD_MODNAME);	\
+	return 0;					\
+}							\
+EXPORT_SYMBOL(x##_test)
+#endif /* _TEST_NVDIMM_WATERMARK_H_ */