[PATCH v4 1/2] rust: bindings: set HZ to CONFIG_HZ

[FUJITA Tomonori <tomo@flapping.org>]

From: FUJITA Tomonori <fujita.tomonori@gmail.com>

include/uapi/asm-generic/param.h defines HZ as __USER_HZ and
include/asm-generic/param.h then sets it to CONFIG_HZ. bindgen keeps the
first definition of a macro and ignores a later #undef, so the generated
binding is __USER_HZ.

Redefine HZ in rust/bindings/lib.rs, the same way compat_ptr_ioctl is
redefined there. Nothing in the tree reads bindings::HZ today, so this
prevents accidental misuse rather than fixing a bug.

Suggested-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Signed-off-by: FUJITA Tomonori <fujita.tomonori@gmail.com>
---
 rust/bindings/lib.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/rust/bindings/lib.rs b/rust/bindings/lib.rs
index 439ab88a5da1..98313fc31024 100644
--- a/rust/bindings/lib.rs
+++ b/rust/bindings/lib.rs
@@ -83,3 +83,8 @@ mod bindings_helper {
         None
     }
 };
+
+// `bindgen` keeps the first definition of a macro and ignores a later `#undef`.
+// The generated `HZ` is therefore `__USER_HZ` from
+// `include/uapi/asm-generic/param.h`, not `CONFIG_HZ`.
+pub const HZ: u32 = CONFIG_HZ;
-- 
2.43.0