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Peter Anvin" , Andrew Morton , Dave Chinner , Qi Zheng , Roman Gushchin , Muchun Song , Peter Zijlstra , Juri Lelli , Vincent Guittot , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , K Prateek Nayak , Uladzislau Rezki , David Hildenbrand , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Kees Cook , Sebastian Andrzej Siewior , Clark Williams , suleiman@google.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org, linux-rt-devel@lists.linux.dev Content-Type: text/plain; charset="utf-8" X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260901_022736_052406_DDC96912 X-CRM114-Status: GOOD ( 23.79 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Aug 27, 2026 at 04:29:46PM -0700, David Stevens wrote: > Annotate various blocking locations with the PF_RECLAIMABLE_STACK. > > Signed-off-by: David Stevens > --- > drivers/android/binder/thread.rs | 14 +++++++++++++ > fs/eventpoll.c | 3 +++ > fs/pipe.c | 28 ++++++++++++++++--------- > fs/select.c | 3 +++ > kernel/futex/waitwake.c | 3 +++ > kernel/signal.c | 36 +++++++++++++++++++------------- > kernel/time/hrtimer.c | 3 +++ > rust/kernel/task.rs | 16 ++++++++++++++ > 8 files changed, 82 insertions(+), 24 deletions(-) > > diff --git a/drivers/android/binder/thread.rs b/drivers/android/binder/thread.rs > index bc0ef8927905..be62f7fd43ca 100644 > --- a/drivers/android/binder/thread.rs > +++ b/drivers/android/binder/thread.rs > @@ -538,13 +538,21 @@ fn get_work_local(self: &Arc, wait: bool) -> Result > // Loop waiting only on the local queue (i.e., not registering with the process queue). > let mut inner = self.inner.lock(); > + // SAFETY: Only accessed locally in this function > + let current = unsafe { Task::current() }; You can invoke kernel::current!() instead to avoid unsafe here. > loop { > if let Some(work) = inner.pop_work() { > return Ok(Some(work)); > } > > inner.looper_flags |= LOOPER_WAITING; > + > + current.set_flag_bits(bindings::PF_RECLAIMABLE_STACK); > + > let signal_pending = self.work_condvar.wait_interruptible_freezable(&mut inner); > + > + current.clear_flag_bits(bindings::PF_RECLAIMABLE_STACK); It would be nicer to define a guard type like you did in C so that this is less "manual". > diff --git a/rust/kernel/task.rs b/rust/kernel/task.rs > index 38273f4eedb5..6168f058343a 100644 > --- a/rust/kernel/task.rs > +++ b/rust/kernel/task.rs > @@ -344,6 +344,22 @@ pub fn group_leader(&self) -> &Task { > // only be used while `current` is still valid, thus still running. > unsafe { &*ptr.cast() } > } > + > + /// Sets the given task flag bits on the current task. > + #[inline] > + pub fn set_flag_bits(&self, set: u32) { > + // SAFETY: The `flags` field of `current` is not modified from other threads, so > + // the non-atomic update isn't a race. > + unsafe { (*self.as_ptr()).flags |= set } > + } > + > + /// Clears the given task flag bits on the current task. > + #[inline] > + pub fn clear_flag_bits(&self, clear: u32) { > + // SAFETY: The `flags` field of `current` is not modified from other threads, so > + // the non-atomic update isn't a race. > + unsafe { (*self.as_ptr()).flags &= !clear } > + } It looks like the indentation here is a bit off. Please try invoking 'make rustfmt' to reformat this code. Alice