linux-kernel - [PATCH v3 05/13] rust: hrtimer: allow timer restart from timer handler

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20241017-hrtimer-v3-v6-12-rc2-v3-5-59a75cbb44da@kernel.org>
Date: Thu, 17 Oct 2024 15:04:32 +0200
From: Andreas Hindborg <a.hindborg@...nel.org>
To: Miguel Ojeda <ojeda@...nel.org>, 
 Anna-Maria Behnsen <anna-maria@...utronix.de>, 
 Frederic Weisbecker <frederic@...nel.org>, 
 Thomas Gleixner <tglx@...utronix.de>
Cc: Alex Gaynor <alex.gaynor@...il.com>, Boqun Feng <boqun.feng@...il.com>, 
 Gary Guo <gary@...yguo.net>, 
 Björn Roy Baron <bjorn3_gh@...tonmail.com>, 
 Benno Lossin <benno.lossin@...ton.me>, Alice Ryhl <aliceryhl@...gle.com>, 
 Trevor Gross <tmgross@...ch.edu>, Lyude Paul <lyude@...hat.com>, 
 rust-for-linux@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Andreas Hindborg <a.hindborg@...nel.org>
Subject: [PATCH v3 05/13] rust: hrtimer: allow timer restart from timer
 handler

This patch allows timer handlers to report that they want a timer to be
restarted after the timer handler has finished executing.

Also update the `hrtimer` documentation to showcase the new feature.

Signed-off-by: Andreas Hindborg <a.hindborg@...nel.org>
---
 rust/kernel/hrtimer.rs     | 28 +++++++++++++++++++++++++++-
 rust/kernel/hrtimer/arc.rs |  4 +---
 2 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/rust/kernel/hrtimer.rs b/rust/kernel/hrtimer.rs
index 6427b0450c694105190c8cddea0c768ab195aca2..eeed2afd501b64b94d57cc658616659e28785078 100644
--- a/rust/kernel/hrtimer.rs
+++ b/rust/kernel/hrtimer.rs
@@ -176,7 +176,7 @@ pub trait TimerCallback {
     type CallbackTargetParameter<'a>;
 
     /// Called by the timer logic when the timer fires.
-    fn run(this: Self::CallbackTargetParameter<'_>)
+    fn run(this: Self::CallbackTargetParameter<'_>) -> TimerRestart
     where
         Self: Sized;
 }
@@ -270,6 +270,32 @@ unsafe fn start(self_ptr: *const Self, expires: Ktime) {
     }
 }
 
+/// Restart policy for timers.
+pub enum TimerRestart {
+    /// Timer should not be restarted.
+    NoRestart,
+    /// Timer should be restarted.
+    Restart,
+}
+
+impl From<u32> for TimerRestart {
+    fn from(value: bindings::hrtimer_restart) -> Self {
+        match value {
+            0 => Self::NoRestart,
+            _ => Self::Restart,
+        }
+    }
+}
+
+impl From<TimerRestart> for bindings::hrtimer_restart {
+    fn from(value: TimerRestart) -> Self {
+        match value {
+            TimerRestart::NoRestart => bindings::hrtimer_restart_HRTIMER_NORESTART,
+            TimerRestart::Restart => bindings::hrtimer_restart_HRTIMER_RESTART,
+        }
+    }
+}
+
 /// Use to implement the [`HasTimer<T>`] trait.
 ///
 /// See [`module`] documentation for an example.
diff --git a/rust/kernel/hrtimer/arc.rs b/rust/kernel/hrtimer/arc.rs
index 881de053ecad866a26e46a0123ec2bf38511c2bc..c6283bd0dbb10dbc733c3f4092f107db2f3c5c5f 100644
--- a/rust/kernel/hrtimer/arc.rs
+++ b/rust/kernel/hrtimer/arc.rs
@@ -82,8 +82,6 @@ impl<U> RawTimerCallback for Arc<U>
         // timer. This `U` is contained in an `Arc`.
         let receiver = unsafe { ArcBorrow::from_raw(data_ptr) };
 
-        U::run(receiver);
-
-        bindings::hrtimer_restart_HRTIMER_NORESTART
+        U::run(receiver).into()
     }
 }

-- 
2.46.0