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The only purpose served by these macros are to create names and >> static lock classes so they can be tracked by lockdep. >>=20 >> I've come up with an approach that uses `Location::caller` and Rust's >> `#[track_caller]` feature for this purpose instead. `Location::caller()` >> will return a `&'static Location<'static>` that lives in `.rodata`. As >> only addresses matter for static objects, the address of the `Location` >> themselves could be used for lock classes. The `Location` is of 2 * usiz= e + >> 8 bytes, so they could host 2 lock class keys, so `DelayedWork` which ne= eds >> two lock classes can also use this mechanism. >>=20 >> The `Location::caller` could also be used to provide the name; currently= , >> `optional_name` just uses `file_name:line_number` as the name, and this >> information is available in `Location`. However, `Location` encodes them >> using file name as a C string plus two `u32`'s for line and column numbe= r, >> so it cannot provide a single name. I came up with an alternative method= , >> which is to use a special string, which lockdep can recognize and delega= te >> back to Rust to print it. > > Perhaps add some sample output so us simple folk that still think rust > looks like line noise can have an idea of what it'll look like. Because > I just cannot make much sense of the above. The above is mostly about the Rust implementation detail. On the lockdep si= de, essentially the name will be "(rust)", while the actual name can be retriev= ed from the lock class key. So for let foo =3D KBox::pin_init(Mutex::new(42)); in, say, foo.c:123 it will eventually call struct rust_location *loc =3D /* static generated by the Rust compiler = */; mutex_init_lockdep(foo, "(rust)", (struct lock_class_key *)loc) And when "(rust)" is encountered as lock class name, instead of printing th= e string as is, lockdep will call lockdep_print_rust_name(loc) which will be doing essentially pr_cont("foo.c:123"); Best, Gary