Commit Graph

4 Commits

Author SHA1 Message Date
Maxim Levitsky 84c5935da5 rust: add helper for mutex_trylock
JIRA: https://issues.redhat.com/browse/RHEL-74410

commit 4dbe28c0fabd69842890ba38f185b96664cba26a
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Wed May 28 10:34:30 2025 +0200

    rust: add helper for mutex_trylock

    After commit c5b6ababd21a ("locking/mutex: implement mutex_trylock_nested",
    currently in the KVM tree) mutex_trylock() will be a macro when lockdep is
    enabled.  Rust therefore needs the corresponding helper.  Just add it and
    the rust/bindings/bindings_helpers_generated.rs Makefile rules will do
    their thing.

    Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
    Message-ID: <20250528083431.1875345-1-pbonzini@redhat.com>
    Acked-by: Miguel Ojeda <ojeda@kernel.org>
    Reviewed-by: Alice Ryhl <aliceryhl@google.com>
    Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
2025-06-25 15:57:33 -04:00
Dirk Behme d065cc7605 rust: mutex: fix __mutex_init() usage in case of PREEMPT_RT
In case CONFIG_PREEMPT_RT is enabled __mutex_init() becomes a macro
instead of an extern function (simplified from
include/linux/mutex.h):

    #ifndef CONFIG_PREEMPT_RT
    extern void __mutex_init(struct mutex *lock, const char *name,
    			 struct lock_class_key *key);
    #else
    #define __mutex_init(mutex, name, key)		\
    do {						\
	rt_mutex_base_init(&(mutex)->rtmutex);		\
    	__mutex_rt_init((mutex), name, key);		\
    } while (0)
    #endif

The macro isn't resolved by bindgen, then. What results in a build
error:

error[E0425]: cannot find function `__mutex_init` in crate `bindings`
     --> rust/kernel/sync/lock/mutex.rs:104:28
      |
104   |           unsafe { bindings::__mutex_init(ptr, name, key) }
      |                              ^^^^^^^^^^^^ help: a function with a similar name exists: `__mutex_rt_init`
      |
     ::: rust/bindings/bindings_generated.rs:23722:5
      |
23722 | /     pub fn __mutex_rt_init(
23723 | |         lock: *mut mutex,
23724 | |         name: *const core::ffi::c_char,
23725 | |         key: *mut lock_class_key,
23726 | |     );
      | |_____- similarly named function `__mutex_rt_init` defined here

Fix this by adding a helper.

As explained by Gary Guo in [1] no #ifdef CONFIG_PREEMPT_RT
is needed here as rust/bindings/lib.rs prefers externed function to
helpers if an externed function exists.

Reported-by: Conor Dooley <conor@kernel.org>
Link: https://lore.kernel.org/rust-for-linux/20240913-shack-estate-b376a65921b1@spud/
Link: https://lore.kernel.org/rust-for-linux/20240915123626.1a170103.gary@garyguo.net/ [1]
Fixes: 6d20d629c6 ("rust: lock: introduce `Mutex`")
Signed-off-by: Dirk Behme <dirk.behme@de.bosch.com>
Tested-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240916073752.3123484-1-dirk.behme@de.bosch.com
[ Reworded to include the proper example by Dirk. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-09-26 21:22:15 +02:00
Gary Guo e26fa54604 rust: kbuild: auto generate helper exports
This removes the need to explicitly export all symbols.

Generate helper exports similarly to what's currently done for Rust
crates. These helpers are exclusively called from within Rust code and
therefore can be treated similar as other Rust symbols.

Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Tested-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20240817165302.3852499-1-gary@garyguo.net
[ Fixed dependency path, reworded slightly, edited comment a bit and
  rebased on top of the changes made when applying Andreas' patch
  (e.g. no `README.md` anymore, so moved the edits).  - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-19 11:09:02 +02:00
Andreas Hindborg 876346536c rust: kbuild: split up helpers.c
This patch splits up the rust helpers C file. When rebasing patch sets on
upstream linux, merge conflicts in helpers.c is common and time consuming
[1]. Thus, split the file so that each kernel component can live in a
separate file.

This patch lists helper files explicitly and thus conflicts in the file
list is still likely. However, they should be more simple to resolve than
the conflicts usually seen in helpers.c.

[ Removed `README.md` and undeleted the original comment since now,
  in v3 of the series, we have a `helpers.c` again; which also allows
  us to keep the "Sorted alphabetically" line and makes the diff easier.

  In addition, updated the Documentation/ mentions of the file, reworded
  title and removed blank lines at the end of `page.c`.  - Miguel ]

Link: https://rust-for-linux.zulipchat.com/#narrow/stream/288089-General/topic/Splitting.20up.20helpers.2Ec/near/426694012 [1]
Signed-off-by: Andreas Hindborg <a.hindborg@samsung.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Dirk Behme <dirk.behme@de.bosch.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Benno Lossin <benno.lossin@proton.me>
Link: https://lore.kernel.org/r/20240815103016.2771842-1-nmi@metaspace.dk
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2024-08-18 23:34:26 +02:00