[PATCH v3 2/2] rust: add system_percpu() around the new system_percpu_wq

[Marco Crivellari]

The C code defines 2 new workqueues: system_percpu_wq and system_dfl_wq,
respectively the futures replacement for system_wq and system_unbound_wq.

This change introduce system_percpu(), that use the new system_percpu_wq.

system_wq will be replaced in a future release cycle and should
not be used.

Suggested-by: Tejun Heo <tj@xxxxxxxxxx>
Signed-off-by: Marco Crivellari <marco.crivellari@xxxxxxxx>
---
 rust/kernel/workqueue.rs | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/rust/kernel/workqueue.rs b/rust/kernel/workqueue.rs
index 300cc2bfe012..05f213444b91 100644
--- a/rust/kernel/workqueue.rs
+++ b/rust/kernel/workqueue.rs
@@ -940,11 +940,26 @@ unsafe impl<T, const ID: u64> RawDelayedWorkItem<ID> for Pin<KBox<T>>
 /// users which expect relatively short queue flush time.
 ///
 /// Callers shouldn't queue work items which can run for too long.
+///
+/// Note: `system_wq` will be removed in a future release cycle. Use [`system_percpu_wq`] instead.
 pub fn system() -> &'static Queue {
     // SAFETY: `system_wq` is a C global, always available.
     unsafe { Queue::from_raw(bindings::system_wq) }
 }
 
+/// Returns the system work queue (`system_percpu_wq`).
+///
+/// It is the one used by `schedule[_delayed]_work[_on]()`. Multi-CPU multi-threaded. There are
+/// users which expect relatively short queue flush time.
+///
+/// Callers shouldn't queue work items which can run for too long.
+///
+/// Note: `system_percpu_wq` will replace ['system_wq`] in a future relase cycle.
+pub fn system_percpu() -> &'static Queue {
+    // SAFETY: `system_percpu_wq` is a C global, always available.
+    unsafe { Queue::from_raw(bindings::system_percpu_wq) }
+}
+
 /// Returns the system high-priority work queue (`system_highpri_wq`).
 ///
 /// It is similar to the one returned by [`system`] but for work items which require higher
-- 
2.51.0