[RESEND PATCH v2 00/19] hrtimers: Consolidate hrtimer initialization - Part 1

[RESEND PATCH v2 00/19] hrtimers: Consolidate hrtimer initialization - Part 1

[Nam Cao]

(resend due to broken emails)

This is a follow up to version 1, which can be found here:

    https://lore.kernel.org/lkml/cover.1729864615.git.namcao@linutronix.de/

hrtimers must be initialized with a hrtimer_init() variant, and after that
the timer's callback function must be setup separately.

This separate initialization is error prone and awkward to use. The
separate initialization is also problematic for a clean Rust abstraction.

A combined setup function like timer_setup() is less error prone and
simpler to use.

This first part of the conversion provides:

  - a set of hrtimer_setup*() variants, which take the function pointer as
    argument.

  - hrtimer_update_function() which allows to change the callback function
    after initialization with the proper safety checks in place.

  - conversion of the hrtimer_init*_on_stack() variants

  - some minor cleanups

The remaining users will be converted in follow up series.

Most conversions were done with Coccinelle. See sematic patch below.

Changes versus v1:
  - Open code kvm_xen_init_vcpu() (Sean)
  - Drop the can/bcm patch (Oliver)
  - Folded the removal of hrtimer_init_sleeper() (tglx)
  - Update change logs and cover letter

The series applies on top of:

    git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git timers/core

and is also available from git:

    git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git hrtimer-setup-part1-v2

Best regards,

Nam

---
virtual patch
@@ expression timer, clock, mode, func; @@
- hrtimer_init(timer, clock, mode);
  ...
- timer->function = func;
+ hrtimer_setup(timer, func, clock, mode);

@@ expression timer, clock, mode, func; @@
- hrtimer_init(&timer, clock, mode);
  ...
- timer.function = func;
+ hrtimer_setup(&timer, func, clock, mode);

@@ expression timer, clock, mode, func; @@
- hrtimer_init_on_stack(&timer, clock, mode);
  ...
- timer.function = func;
+ hrtimer_setup_on_stack(&timer, func, clock, mode);

@@ expression timer, clock, mode; @@
- hrtimer_init_sleeper_on_stack(timer, clock, mode);
+ hrtimer_setup_sleeper_on_stack(timer, clock, mode);

---
 arch/x86/kvm/xen.c                             |  12 +--
 drivers/gpu/drm/i915/i915_request.c            |  17 ++--
 drivers/net/wireless/ralink/rt2x00/rt2x00usb.c |   2 -
 fs/aio.c                                       |   2 +-
 include/linux/hrtimer.h                        |  51 +++++++-----
 include/linux/wait.h                           |   4 +-
 io_uring/io_uring.c                            |   7 +-
 io_uring/timeout.c                             |   1 -
 kernel/futex/core.c                            |   6 +-
 kernel/sched/idle.c                            |   4 +-
 kernel/time/alarmtimer.c                       |   9 +-
 kernel/time/hrtimer.c                          | 110 ++++++++++++++++++-------
 kernel/time/sleep_timeout.c                    |   2 +-
 net/core/pktgen.c                              |   2 +-
 14 files changed, 136 insertions(+), 93 deletions(-)

[RESEND PATCH v2 01/19] hrtimers: Add missing hrtimer_init() trace points

[Nam Cao]

hrtimer_init*_on_stack() is not covered by tracing when
CONFIG_DEBUG_OBJECTS_TIMERS=y.

Rework the functions similar to hrtimer_init() and hrtimer_init_sleeper()
so that the hrtimer_init() tracepoint is unconditionally available.

The rework makes hrtimer_init_sleeper() unused. Delete it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h | 19 +-----------
 kernel/time/hrtimer.c   | 65 +++++++++++++++++++++++------------------
 2 files changed, 37 insertions(+), 47 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index aa1e65ccb615..5aa9d57528c4 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -228,32 +228,15 @@ static inline void hrtimer_cancel_wait_running(struct hrtimer *timer)
 /* Initialize timers: */
 extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
 			 enum hrtimer_mode mode);
-extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id,
-				 enum hrtimer_mode mode);
-
-#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
 extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
 				  enum hrtimer_mode mode);
 extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
 					  clockid_t clock_id,
 					  enum hrtimer_mode mode);
 
+#ifdef CONFIG_DEBUG_OBJECTS_TIMERS
 extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
 #else
-static inline void hrtimer_init_on_stack(struct hrtimer *timer,
-					 clockid_t which_clock,
-					 enum hrtimer_mode mode)
-{
-	hrtimer_init(timer, which_clock, mode);
-}
-
-static inline void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
-						 clockid_t clock_id,
-						 enum hrtimer_mode mode)
-{
-	hrtimer_init_sleeper(sl, clock_id, mode);
-}
-
 static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { }
 #endif
 
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 04f7d8a392c3..4b0507cf38ea 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -417,6 +417,11 @@ static inline void debug_hrtimer_init(struct hrtimer *timer)
 	debug_object_init(timer, &hrtimer_debug_descr);
 }
 
+static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer)
+{
+	debug_object_init_on_stack(timer, &hrtimer_debug_descr);
+}
+
 static inline void debug_hrtimer_activate(struct hrtimer *timer,
 					  enum hrtimer_mode mode)
 {
@@ -428,28 +433,6 @@ static inline void debug_hrtimer_deactivate(struct hrtimer *timer)
 	debug_object_deactivate(timer, &hrtimer_debug_descr);
 }
 
-static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
-			   enum hrtimer_mode mode);
-
-void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
-			   enum hrtimer_mode mode)
-{
-	debug_object_init_on_stack(timer, &hrtimer_debug_descr);
-	__hrtimer_init(timer, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
-
-static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
-				   clockid_t clock_id, enum hrtimer_mode mode);
-
-void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
-				   clockid_t clock_id, enum hrtimer_mode mode)
-{
-	debug_object_init_on_stack(&sl->timer, &hrtimer_debug_descr);
-	__hrtimer_init_sleeper(sl, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
-
 void destroy_hrtimer_on_stack(struct hrtimer *timer)
 {
 	debug_object_free(timer, &hrtimer_debug_descr);
@@ -459,6 +442,7 @@ EXPORT_SYMBOL_GPL(destroy_hrtimer_on_stack);
 #else
 
 static inline void debug_hrtimer_init(struct hrtimer *timer) { }
+static inline void debug_hrtimer_init_on_stack(struct hrtimer *timer) { }
 static inline void debug_hrtimer_activate(struct hrtimer *timer,
 					  enum hrtimer_mode mode) { }
 static inline void debug_hrtimer_deactivate(struct hrtimer *timer) { }
@@ -472,6 +456,13 @@ debug_init(struct hrtimer *timer, clockid_t clockid,
 	trace_hrtimer_init(timer, clockid, mode);
 }
 
+static inline void debug_init_on_stack(struct hrtimer *timer, clockid_t clockid,
+				       enum hrtimer_mode mode)
+{
+	debug_hrtimer_init_on_stack(timer);
+	trace_hrtimer_init(timer, clockid, mode);
+}
+
 static inline void debug_activate(struct hrtimer *timer,
 				  enum hrtimer_mode mode)
 {
@@ -1600,6 +1591,23 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
+/**
+ * hrtimer_init_on_stack - initialize a timer in stack memory
+ * @timer:	The timer to be initialized
+ * @clock_id:	The clock to be used
+ * @mode:       The timer mode
+ *
+ * Similar to hrtimer_init(), except that this one must be used if struct hrtimer is in stack
+ * memory.
+ */
+void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
+			   enum hrtimer_mode mode)
+{
+	debug_init_on_stack(timer, clock_id, mode);
+	__hrtimer_init(timer, clock_id, mode);
+}
+EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
+
 /*
  * A timer is active, when it is enqueued into the rbtree or the
  * callback function is running or it's in the state of being migrated
@@ -1944,7 +1952,7 @@ void hrtimer_sleeper_start_expires(struct hrtimer_sleeper *sl,
 	 * Make the enqueue delivery mode check work on RT. If the sleeper
 	 * was initialized for hard interrupt delivery, force the mode bit.
 	 * This is a special case for hrtimer_sleepers because
-	 * hrtimer_init_sleeper() determines the delivery mode on RT so the
+	 * __hrtimer_init_sleeper() determines the delivery mode on RT so the
 	 * fiddling with this decision is avoided at the call sites.
 	 */
 	if (IS_ENABLED(CONFIG_PREEMPT_RT) && sl->timer.is_hard)
@@ -1987,19 +1995,18 @@ static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
 }
 
 /**
- * hrtimer_init_sleeper - initialize sleeper to the given clock
+ * hrtimer_init_sleeper_on_stack - initialize a sleeper in stack memory
  * @sl:		sleeper to be initialized
  * @clock_id:	the clock to be used
  * @mode:	timer mode abs/rel
  */
-void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id,
-			  enum hrtimer_mode mode)
+void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
+				   clockid_t clock_id, enum hrtimer_mode mode)
 {
-	debug_init(&sl->timer, clock_id, mode);
+	debug_init_on_stack(&sl->timer, clock_id, mode);
 	__hrtimer_init_sleeper(sl, clock_id, mode);
-
 }
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper);
+EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
 
 int nanosleep_copyout(struct restart_block *restart, struct timespec64 *ts)
 {
-- 
2.39.5

[RESEND PATCH v2 02/19] drm/i915/request: Remove unnecessary modification of hrtimer::function

[Nam Cao]

When a request is created, the hrtimer is not initialized and only its
'function' field is set to NULL. The hrtimer is only initialized when the
request is enqueued. The point of setting 'function' to NULL is that, it
can be used to check whether hrtimer_try_to_cancel() should be called while
retiring the request.

This "trick" is unnecessary, because hrtimer_try_to_cancel() already does
its own check whether the timer is armed. If the timer is not armed,
hrtimer_try_to_cancel() returns 0.

Fully initialize the timer when the request is created, which allows to
make the hrtimer::function field private once all users of hrtimer_init()
are converted to hrtimer_setup(), which requires a valid callback function
to be set.

Because hrtimer_try_to_cancel() returns 0 if the timer is not armed, the
logic to check whether to call i915_request_put() remains equivalent.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_request.c | 17 +++++++++--------
 1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_request.c b/drivers/gpu/drm/i915/i915_request.c
index 519e096c607c..8f62cfa23fb7 100644
--- a/drivers/gpu/drm/i915/i915_request.c
+++ b/drivers/gpu/drm/i915/i915_request.c
@@ -273,11 +273,6 @@ i915_request_active_engine(struct i915_request *rq,
 	return ret;
 }
 
-static void __rq_init_watchdog(struct i915_request *rq)
-{
-	rq->watchdog.timer.function = NULL;
-}
-
 static enum hrtimer_restart __rq_watchdog_expired(struct hrtimer *hrtimer)
 {
 	struct i915_request *rq =
@@ -294,6 +289,14 @@ static enum hrtimer_restart __rq_watchdog_expired(struct hrtimer *hrtimer)
 	return HRTIMER_NORESTART;
 }
 
+static void __rq_init_watchdog(struct i915_request *rq)
+{
+	struct i915_request_watchdog *wdg = &rq->watchdog;
+
+	hrtimer_init(&wdg->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	wdg->timer.function = __rq_watchdog_expired;
+}
+
 static void __rq_arm_watchdog(struct i915_request *rq)
 {
 	struct i915_request_watchdog *wdg = &rq->watchdog;
@@ -304,8 +307,6 @@ static void __rq_arm_watchdog(struct i915_request *rq)
 
 	i915_request_get(rq);
 
-	hrtimer_init(&wdg->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-	wdg->timer.function = __rq_watchdog_expired;
 	hrtimer_start_range_ns(&wdg->timer,
 			       ns_to_ktime(ce->watchdog.timeout_us *
 					   NSEC_PER_USEC),
@@ -317,7 +318,7 @@ static void __rq_cancel_watchdog(struct i915_request *rq)
 {
 	struct i915_request_watchdog *wdg = &rq->watchdog;
 
-	if (wdg->timer.function && hrtimer_try_to_cancel(&wdg->timer) > 0)
+	if (hrtimer_try_to_cancel(&wdg->timer) > 0)
 		i915_request_put(rq);
 }
 
-- 
2.39.5

[RESEND PATCH v2 03/19] KVM: x86/xen: Initialize hrtimer in kvm_xen_init_vcpu()

[Nam Cao]

The hrtimer is initialized in the KVM_XEN_VCPU_SET_ATTR ioctl. That caused
problem in the past, because the hrtimer can be initialized multiple times,
which was fixed by commit af735db31285 ("KVM: x86/xen: Initialize Xen timer
only once"). This commit avoids initializing the timer multiple times by
checking the field 'function' of struct hrtimer to determine if it has
already been initialized.

This is not required and in the way to make the function field private.

Move the hrtimer initialization into kvm_xen_init_vcpu() so that it will
only be initialized once.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Acked-by: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: x86@kernel.org
Cc: kvm@vger.kernel.org
---
 arch/x86/kvm/xen.c | 12 ++----------
 1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index 622fe24da910..a909b817b9c0 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -263,13 +263,6 @@ static void kvm_xen_stop_timer(struct kvm_vcpu *vcpu)
 	atomic_set(&vcpu->arch.xen.timer_pending, 0);
 }
 
-static void kvm_xen_init_timer(struct kvm_vcpu *vcpu)
-{
-	hrtimer_init(&vcpu->arch.xen.timer, CLOCK_MONOTONIC,
-		     HRTIMER_MODE_ABS_HARD);
-	vcpu->arch.xen.timer.function = xen_timer_callback;
-}
-
 static void kvm_xen_update_runstate_guest(struct kvm_vcpu *v, bool atomic)
 {
 	struct kvm_vcpu_xen *vx = &v->arch.xen;
@@ -1070,9 +1063,6 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
 			break;
 		}
 
-		if (!vcpu->arch.xen.timer.function)
-			kvm_xen_init_timer(vcpu);
-
 		/* Stop the timer (if it's running) before changing the vector */
 		kvm_xen_stop_timer(vcpu);
 		vcpu->arch.xen.timer_virq = data->u.timer.port;
@@ -2235,6 +2225,8 @@ void kvm_xen_init_vcpu(struct kvm_vcpu *vcpu)
 	vcpu->arch.xen.poll_evtchn = 0;
 
 	timer_setup(&vcpu->arch.xen.poll_timer, cancel_evtchn_poll, 0);
+	hrtimer_init(&vcpu->arch.xen.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
+	vcpu->arch.xen.timer.function = xen_timer_callback;
 
 	kvm_gpc_init(&vcpu->arch.xen.runstate_cache, vcpu->kvm);
 	kvm_gpc_init(&vcpu->arch.xen.runstate2_cache, vcpu->kvm);
-- 
2.39.5

[RESEND PATCH v2 04/19] wifi: rt2x00: Remove redundant hrtimer_init()

[Nam Cao]

rt2x00usb_probe() executes a hrtimer_init() for txstatus_timer. Afterwards,
rt2x00lib_probe_dev() is called which also initializes this txstatus_timer
with the same settings.

Remove the redundant hrtimer_init() call in rt2x00usb_probe().

Signed-off-by: Nam Cao <namcao@linutronix.de>
Acked-by: Kalle Valo <kvalo@kernel.org>
Cc: linux-wireless@vger.kernel.org
---
 drivers/net/wireless/ralink/rt2x00/rt2x00usb.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
index 8fd22c69855f..a6d50149e0c3 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
@@ -823,8 +823,6 @@ int rt2x00usb_probe(struct usb_interface *usb_intf,
 
 	INIT_WORK(&rt2x00dev->rxdone_work, rt2x00usb_work_rxdone);
 	INIT_WORK(&rt2x00dev->txdone_work, rt2x00usb_work_txdone);
-	hrtimer_init(&rt2x00dev->txstatus_timer, CLOCK_MONOTONIC,
-		     HRTIMER_MODE_REL);
 
 	retval = rt2x00usb_alloc_reg(rt2x00dev);
 	if (retval)
-- 
2.39.5

[RESEND PATCH v2 05/19] io_uring: Remove redundant hrtimer's callback function setup

[Nam Cao]

The IORING_OP_TIMEOUT command uses hrtimer underneath. The timer's callback
function is setup in io_timeout(), and then the callback function is setup
again when the timer is rearmed.

Since the callback function is the same for both cases, the latter setup is
redundant, therefore remove it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
---
 io_uring/timeout.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/io_uring/timeout.c b/io_uring/timeout.c
index 9973876d91b0..2ffe5e1dc68a 100644
--- a/io_uring/timeout.c
+++ b/io_uring/timeout.c
@@ -76,7 +76,6 @@ static void io_timeout_complete(struct io_kiocb *req, struct io_tw_state *ts)
 			/* re-arm timer */
 			spin_lock_irq(&ctx->timeout_lock);
 			list_add(&timeout->list, ctx->timeout_list.prev);
-			data->timer.function = io_timeout_fn;
 			hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
 			spin_unlock_irq(&ctx->timeout_lock);
 			return;
-- 
2.39.5

Re: [RESEND PATCH v2 05/19] io_uring: Remove redundant hrtimer's callback function setup

[Jens Axboe]

On 10/31/24 9:14 AM, Nam Cao wrote:
> The IORING_OP_TIMEOUT command uses hrtimer underneath. The timer's callback
> function is setup in io_timeout(), and then the callback function is setup
> again when the timer is rearmed.
> 
> Since the callback function is the same for both cases, the latter setup is
> redundant, therefore remove it.
> 
> Signed-off-by: Nam Cao <namcao@linutronix.de>
> Cc: Jens Axboe <axboe@kernel.dk>
> ---
>  io_uring/timeout.c | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/io_uring/timeout.c b/io_uring/timeout.c
> index 9973876d91b0..2ffe5e1dc68a 100644
> --- a/io_uring/timeout.c
> +++ b/io_uring/timeout.c
> @@ -76,7 +76,6 @@ static void io_timeout_complete(struct io_kiocb *req, struct io_tw_state *ts)
>  			/* re-arm timer */
>  			spin_lock_irq(&ctx->timeout_lock);
>  			list_add(&timeout->list, ctx->timeout_list.prev);
> -			data->timer.function = io_timeout_fn;
>  			hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
>  			spin_unlock_irq(&ctx->timeout_lock);
>  			return;

Should be fine, io_timeout_complete() is only used for non-linked
timeouts.

Reviewed-by: Jens Axboe <axboe@kernel.dk:

-- 
Jens Axboe

[RESEND PATCH v2 06/19] hrtimers: Introduce hrtimer_setup() to replace hrtimer_init()

[Nam Cao]

To initialize hrtimer, hrtimer_init() needs to be called and also
hrtimer::function must be set. This is error-prone and awkward to use.

Introduce hrtimer_setup() which does both of these things, so that users of
hrtimer can be simplified.

The new setup function also has a sanity check for the provided function
pointer. If NULL, a warning is emitted and a dummy callback installed.

hrtimer_init() will be removed as soon as all of its users have been
converted to the new function.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h |  2 ++
 kernel/time/hrtimer.c   | 38 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 40 insertions(+)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 5aa9d57528c4..bcc0715c59a8 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -228,6 +228,8 @@ static inline void hrtimer_cancel_wait_running(struct hrtimer *timer)
 /* Initialize timers: */
 extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
 			 enum hrtimer_mode mode);
+extern void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *),
+			  clockid_t clock_id, enum hrtimer_mode mode);
 extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
 				  enum hrtimer_mode mode);
 extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 4b0507cf38ea..a5ef67edcda9 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1535,6 +1535,11 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id)
 	return HRTIMER_BASE_MONOTONIC;
 }
 
+static enum hrtimer_restart hrtimer_dummy_timeout(struct hrtimer *unused)
+{
+	return HRTIMER_NORESTART;
+}
+
 static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 			   enum hrtimer_mode mode)
 {
@@ -1571,6 +1576,18 @@ static void __hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 	timerqueue_init(&timer->node);
 }
 
+static void __hrtimer_setup(struct hrtimer *timer,
+			    enum hrtimer_restart (*function)(struct hrtimer *),
+			    clockid_t clock_id, enum hrtimer_mode mode)
+{
+	__hrtimer_init(timer, clock_id, mode);
+
+	if (WARN_ON_ONCE(!function))
+		timer->function = hrtimer_dummy_timeout;
+	else
+		timer->function = function;
+}
+
 /**
  * hrtimer_init - initialize a timer to the given clock
  * @timer:	the timer to be initialized
@@ -1591,6 +1608,27 @@ void hrtimer_init(struct hrtimer *timer, clockid_t clock_id,
 }
 EXPORT_SYMBOL_GPL(hrtimer_init);
 
+/**
+ * hrtimer_setup - initialize a timer to the given clock
+ * @timer:	the timer to be initialized
+ * @function:	the callback function
+ * @clock_id:	the clock to be used
+ * @mode:       The modes which are relevant for initialization:
+ *              HRTIMER_MODE_ABS, HRTIMER_MODE_REL, HRTIMER_MODE_ABS_SOFT,
+ *              HRTIMER_MODE_REL_SOFT
+ *
+ *              The PINNED variants of the above can be handed in,
+ *              but the PINNED bit is ignored as pinning happens
+ *              when the hrtimer is started
+ */
+void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *),
+		   clockid_t clock_id, enum hrtimer_mode mode)
+{
+	debug_init(timer, clock_id, mode);
+	__hrtimer_setup(timer, function, clock_id, mode);
+}
+EXPORT_SYMBOL_GPL(hrtimer_setup);
+
 /**
  * hrtimer_init_on_stack - initialize a timer in stack memory
  * @timer:	The timer to be initialized
-- 
2.39.5

[RESEND PATCH v2 07/19] hrtimers: Introduce hrtimer_setup_on_stack()

[Nam Cao]

To initialize hrtimer on stack, hrtimer_init_on_stack() needs to be called
and also hrtimer::function must be set. This is error-prone and awkward to
use.

Introduce hrtimer_setup_on_stack() which does both of these things, so that
users of hrtimer can be simplified.

The new setup function also has a sanity check for the provided function
pointer. If NULL, a warning is emitted and a dummy callback installed.

hrtimer_init_on_stack() will be removed as soon as all of its users have
been converted to the new function.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h |  3 +++
 kernel/time/hrtimer.c   | 19 +++++++++++++++++++
 2 files changed, 22 insertions(+)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index bcc0715c59a8..2da513f8d66a 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -232,6 +232,9 @@ extern void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function
 			  clockid_t clock_id, enum hrtimer_mode mode);
 extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
 				  enum hrtimer_mode mode);
+extern void hrtimer_setup_on_stack(struct hrtimer *timer,
+				   enum hrtimer_restart (*function)(struct hrtimer *),
+				   clockid_t clock_id, enum hrtimer_mode mode);
 extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
 					  clockid_t clock_id,
 					  enum hrtimer_mode mode);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index a5ef67edcda9..daee4e27f839 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1646,6 +1646,25 @@ void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
 }
 EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
 
+/**
+ * hrtimer_setup_on_stack - initialize a timer on stack memory
+ * @timer:	The timer to be initialized
+ * @function:	the callback function
+ * @clock_id:	The clock to be used
+ * @mode:       The timer mode
+ *
+ * Similar to hrtimer_setup(), except that this one must be used if struct hrtimer is in stack
+ * memory.
+ */
+void hrtimer_setup_on_stack(struct hrtimer *timer,
+			    enum hrtimer_restart (*function)(struct hrtimer *),
+			    clockid_t clock_id, enum hrtimer_mode mode)
+{
+	debug_init_on_stack(timer, clock_id, mode);
+	__hrtimer_setup(timer, function, clock_id, mode);
+}
+EXPORT_SYMBOL_GPL(hrtimer_setup_on_stack);
+
 /*
  * A timer is active, when it is enqueued into the rbtree or the
  * callback function is running or it's in the state of being migrated
-- 
2.39.5

[RESEND PATCH v2 08/19] hrtimers: Introduce hrtimer_setup_sleeper_on_stack()

[Nam Cao]

The hrtimer_init*() API is replaced by hrtimer_setup*() variants to
initialize the timer including the callback function at once.

hrtimer_init_sleeper_on_stack() does not need user to setup the callback
function separately, so a new variant would not be strictly necessary.

Nonetheless, to keep the naming convention consistent, introduce
hrtimer_setup_sleeper_on_stack(). hrtimer_init_on_stack() will be removed
once all users are converted.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h |  2 ++
 kernel/time/hrtimer.c   | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 2da513f8d66a..48872a2b4071 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -238,6 +238,8 @@ extern void hrtimer_setup_on_stack(struct hrtimer *timer,
 extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
 					  clockid_t clock_id,
 					  enum hrtimer_mode mode);
+extern void hrtimer_setup_sleeper_on_stack(struct hrtimer_sleeper *sl, clockid_t clock_id,
+					   enum hrtimer_mode mode);
 
 #ifdef CONFIG_DEBUG_OBJECTS_TIMERS
 extern void destroy_hrtimer_on_stack(struct hrtimer *timer);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index daee4e27f839..1d1f5c03673c 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -2065,6 +2065,20 @@ void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
 }
 EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
 
+/**
+ * hrtimer_setup_sleeper_on_stack - initialize a sleeper in stack memory
+ * @sl:		sleeper to be initialized
+ * @clock_id:	the clock to be used
+ * @mode:	timer mode abs/rel
+ */
+void hrtimer_setup_sleeper_on_stack(struct hrtimer_sleeper *sl,
+				    clockid_t clock_id, enum hrtimer_mode mode)
+{
+	debug_init_on_stack(&sl->timer, clock_id, mode);
+	__hrtimer_init_sleeper(sl, clock_id, mode);
+}
+EXPORT_SYMBOL_GPL(hrtimer_setup_sleeper_on_stack);
+
 int nanosleep_copyout(struct restart_block *restart, struct timespec64 *ts)
 {
 	switch(restart->nanosleep.type) {
-- 
2.39.5

[RESEND PATCH v2 09/19] hrtimers: Introduce hrtimer_update_function()

[Nam Cao]

Some users of hrtimer need to change the callback function after the
initial setup. They write to hrtimer::function directly.

That's not safe under all circumstances as the write is lockless and a
concurrent timer expiry might end up using the wrong function pointer.

Introduce hrtimer_update_function(), which also performs runtime checks
whether it is safe to modify the callback.

This allows to make hrtimer::function private once all users are converted.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 48872a2b4071..6e026730e803 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -327,6 +327,28 @@ static inline int hrtimer_callback_running(struct hrtimer *timer)
 	return timer->base->running == timer;
 }
 
+/**
+ * hrtimer_update_function - Update the timer's callback function
+ * @timer:	Timer to update
+ * @function:	New callback function
+ *
+ * Only safe to call if the timer is not enqueued. Can be called in the callback function if the
+ * timer is not enqueued at the same time (see the comments above HRTIMER_STATE_ENQUEUED).
+ */
+static inline void hrtimer_update_function(struct hrtimer *timer,
+					   enum hrtimer_restart (*function)(struct hrtimer *))
+{
+	guard(raw_spinlock_irqsave)(&timer->base->cpu_base->lock);
+
+	if (WARN_ON_ONCE(hrtimer_is_queued(timer)))
+		return;
+
+	if (WARN_ON_ONCE(!function))
+		return;
+
+	timer->function = function;
+}
+
 /* Forward a hrtimer so it expires after now: */
 extern u64
 hrtimer_forward(struct hrtimer *timer, ktime_t now, ktime_t interval);
-- 
2.39.5

[RESEND PATCH v2 10/19] fs/aio: Switch to use hrtimer_setup_sleeper_on_stack()

[Nam Cao]

hrtimer_setup_sleeper_on_stack() replaces hrtimer_init_sleeper_on_stack()
to keep the naming convention consistent.

Convert the usage site over to it. The conversion was done with Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Christian Brauner <brauner@kernel.org>
---
 fs/aio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/aio.c b/fs/aio.c
index e8920178b50f..a5d331f29943 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1335,7 +1335,7 @@ static long read_events(struct kioctx *ctx, long min_nr, long nr,
 	if (until == 0 || ret < 0 || ret >= min_nr)
 		return ret;
 
-	hrtimer_init_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_setup_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
 	if (until != KTIME_MAX) {
 		hrtimer_set_expires_range_ns(&t.timer, until, current->timer_slack_ns);
 		hrtimer_sleeper_start_expires(&t, HRTIMER_MODE_REL);
-- 
2.39.5

[RESEND PATCH v2 11/19] futex: Switch to use hrtimer_setup_sleeper_on_stack()

[Nam Cao]

hrtimer_setup_sleeper_on_stack() replaces hrtimer_init_sleeper_on_stack()
to keep the naming convention consistent.

Convert the usage site over to it. The conversion was done with Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 kernel/futex/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/futex/core.c b/kernel/futex/core.c
index 136768ae2637..fb7214c7a36f 100644
--- a/kernel/futex/core.c
+++ b/kernel/futex/core.c
@@ -140,9 +140,9 @@ futex_setup_timer(ktime_t *time, struct hrtimer_sleeper *timeout,
 	if (!time)
 		return NULL;
 
-	hrtimer_init_sleeper_on_stack(timeout, (flags & FLAGS_CLOCKRT) ?
-				      CLOCK_REALTIME : CLOCK_MONOTONIC,
-				      HRTIMER_MODE_ABS);
+	hrtimer_setup_sleeper_on_stack(timeout,
+				       (flags & FLAGS_CLOCKRT) ? CLOCK_REALTIME : CLOCK_MONOTONIC,
+				       HRTIMER_MODE_ABS);
 	/*
 	 * If range_ns is 0, calling hrtimer_set_expires_range_ns() is
 	 * effectively the same as calling hrtimer_set_expires().
-- 
2.39.5

[RESEND PATCH v2 12/19] net: pktgen: Switch to use hrtimer_setup_sleeper_on_stack()

[Nam Cao]

hrtimer_setup_sleeper_on_stack() replaces hrtimer_init_sleeper_on_stack()
to keep the naming convention consistent.

Convert the usage site over to it. The conversion was done with Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Jakub Kicinski <kuba@kernel.org>
---
 net/core/pktgen.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 34f68ef74b8f..7e23cacbe66e 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2285,7 +2285,7 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t spin_until)
 	s64 remaining;
 	struct hrtimer_sleeper t;
 
-	hrtimer_init_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
+	hrtimer_setup_sleeper_on_stack(&t, CLOCK_MONOTONIC, HRTIMER_MODE_ABS);
 	hrtimer_set_expires(&t.timer, spin_until);
 
 	remaining = ktime_to_ns(hrtimer_expires_remaining(&t.timer));
-- 
2.39.5

[RESEND PATCH v2 13/19] timers: Switch to use hrtimer_setup_sleeper_on_stack()

[Nam Cao]

hrtimer_setup_sleeper_on_stack() replaces hrtimer_init_sleeper_on_stack()
to keep the naming convention consistent.

Convert the usage sites over to it. The conversion was done with
Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 kernel/time/hrtimer.c       | 5 ++---
 kernel/time/sleep_timeout.c | 2 +-
 2 files changed, 3 insertions(+), 4 deletions(-)

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 1d1f5c03673c..69430467a17d 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -2138,8 +2138,7 @@ static long __sched hrtimer_nanosleep_restart(struct restart_block *restart)
 	struct hrtimer_sleeper t;
 	int ret;
 
-	hrtimer_init_sleeper_on_stack(&t, restart->nanosleep.clockid,
-				      HRTIMER_MODE_ABS);
+	hrtimer_setup_sleeper_on_stack(&t, restart->nanosleep.clockid, HRTIMER_MODE_ABS);
 	hrtimer_set_expires_tv64(&t.timer, restart->nanosleep.expires);
 	ret = do_nanosleep(&t, HRTIMER_MODE_ABS);
 	destroy_hrtimer_on_stack(&t.timer);
@@ -2153,7 +2152,7 @@ long hrtimer_nanosleep(ktime_t rqtp, const enum hrtimer_mode mode,
 	struct hrtimer_sleeper t;
 	int ret = 0;
 
-	hrtimer_init_sleeper_on_stack(&t, clockid, mode);
+	hrtimer_setup_sleeper_on_stack(&t, clockid, mode);
 	hrtimer_set_expires_range_ns(&t.timer, rqtp, current->timer_slack_ns);
 	ret = do_nanosleep(&t, mode);
 	if (ret != -ERESTART_RESTARTBLOCK)
diff --git a/kernel/time/sleep_timeout.c b/kernel/time/sleep_timeout.c
index 3054e5232d20..dfe939f6e4ec 100644
--- a/kernel/time/sleep_timeout.c
+++ b/kernel/time/sleep_timeout.c
@@ -208,7 +208,7 @@ int __sched schedule_hrtimeout_range_clock(ktime_t *expires, u64 delta,
 		return -EINTR;
 	}
 
-	hrtimer_init_sleeper_on_stack(&t, clock_id, mode);
+	hrtimer_setup_sleeper_on_stack(&t, clock_id, mode);
 	hrtimer_set_expires_range_ns(&t.timer, *expires, delta);
 	hrtimer_sleeper_start_expires(&t, mode);
 
-- 
2.39.5

[RESEND PATCH v2 14/19] wait: Switch to use hrtimer_setup_sleeper_on_stack()

[Nam Cao]

hrtimer_setup_sleeper_on_stack() replaces hrtimer_init_sleeper_on_stack()
to keep the naming convention consistent.

Convert the usage site over to it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 include/linux/wait.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/wait.h b/include/linux/wait.h
index 8aa3372f21a0..643b7c7bf376 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -541,8 +541,8 @@ do {										\
 	int __ret = 0;								\
 	struct hrtimer_sleeper __t;						\
 										\
-	hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC,			\
-				      HRTIMER_MODE_REL);			\
+	hrtimer_setup_sleeper_on_stack(&__t, CLOCK_MONOTONIC,			\
+				       HRTIMER_MODE_REL);			\
 	if ((timeout) != KTIME_MAX) {						\
 		hrtimer_set_expires_range_ns(&__t.timer, timeout,		\
 					current->timer_slack_ns);		\
-- 
2.39.5

[RESEND PATCH v2 15/19] hrtimers: Delete hrtimer_init_sleeper_on_stack()

[Nam Cao]

hrtimer_init_sleeper_on_stack() is now unused. Delete it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h |  3 ---
 kernel/time/hrtimer.c   | 14 --------------
 2 files changed, 17 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 6e026730e803..4e4f04b3c0c2 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -235,9 +235,6 @@ extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
 extern void hrtimer_setup_on_stack(struct hrtimer *timer,
 				   enum hrtimer_restart (*function)(struct hrtimer *),
 				   clockid_t clock_id, enum hrtimer_mode mode);
-extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
-					  clockid_t clock_id,
-					  enum hrtimer_mode mode);
 extern void hrtimer_setup_sleeper_on_stack(struct hrtimer_sleeper *sl, clockid_t clock_id,
 					   enum hrtimer_mode mode);
 
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 69430467a17d..376b8182b72e 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -2051,20 +2051,6 @@ static void __hrtimer_init_sleeper(struct hrtimer_sleeper *sl,
 	sl->task = current;
 }
 
-/**
- * hrtimer_init_sleeper_on_stack - initialize a sleeper in stack memory
- * @sl:		sleeper to be initialized
- * @clock_id:	the clock to be used
- * @mode:	timer mode abs/rel
- */
-void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl,
-				   clockid_t clock_id, enum hrtimer_mode mode)
-{
-	debug_init_on_stack(&sl->timer, clock_id, mode);
-	__hrtimer_init_sleeper(sl, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_sleeper_on_stack);
-
 /**
  * hrtimer_setup_sleeper_on_stack - initialize a sleeper in stack memory
  * @sl:		sleeper to be initialized
-- 
2.39.5

[RESEND PATCH v2 16/19] sched/idle: Switch to use hrtimer_setup_on_stack()

[Nam Cao]

hrtimer_setup_on_stack() takes the callback function pointer as argument
and initializes the timer completely.

Replace hrtimer_init_on_stack() and the open coded initialization of
hrtimer::function with the new setup mechanism.

The conversion was done with Coccinelle.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
---
 kernel/sched/idle.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c
index d2f096bb274c..631e42802925 100644
--- a/kernel/sched/idle.c
+++ b/kernel/sched/idle.c
@@ -399,8 +399,8 @@ void play_idle_precise(u64 duration_ns, u64 latency_ns)
 	cpuidle_use_deepest_state(latency_ns);
 
 	it.done = 0;
-	hrtimer_init_on_stack(&it.timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
-	it.timer.function = idle_inject_timer_fn;
+	hrtimer_setup_on_stack(&it.timer, idle_inject_timer_fn, CLOCK_MONOTONIC,
+			       HRTIMER_MODE_REL_HARD);
 	hrtimer_start(&it.timer, ns_to_ktime(duration_ns),
 		      HRTIMER_MODE_REL_PINNED_HARD);
 
-- 
2.39.5

[RESEND PATCH v2 17/19] io_uring: Switch to use hrtimer_setup_on_stack()

[Nam Cao]

hrtimer_setup_on_stack() takes the callback function pointer as argument
and initializes the timer completely.

Replace hrtimer_init_on_stack() and the open coded initialization of
hrtimer::function with the new setup mechanism.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: Jens Axboe <axboe@kernel.dk>
---
 io_uring/io_uring.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index feb61d68dca6..0842aa3f60e7 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2435,13 +2435,14 @@ static int io_cqring_schedule_timeout(struct io_wait_queue *iowq,
 {
 	ktime_t timeout;
 
-	hrtimer_init_on_stack(&iowq->t, clock_id, HRTIMER_MODE_ABS);
 	if (iowq->min_timeout) {
 		timeout = ktime_add_ns(iowq->min_timeout, start_time);
-		iowq->t.function = io_cqring_min_timer_wakeup;
+		hrtimer_setup_on_stack(&iowq->t, io_cqring_min_timer_wakeup, clock_id,
+				       HRTIMER_MODE_ABS);
 	} else {
 		timeout = iowq->timeout;
-		iowq->t.function = io_cqring_timer_wakeup;
+		hrtimer_setup_on_stack(&iowq->t, io_cqring_timer_wakeup, clock_id,
+				       HRTIMER_MODE_ABS);
 	}
 
 	hrtimer_set_expires_range_ns(&iowq->t, timeout, 0);
-- 
2.39.5

[RESEND PATCH v2 18/19] alarmtimer: Switch to use hrtimer_setup() and hrtimer_setup_on_stack()

[Nam Cao]

hrtimer_setup() and hrtimer_setup_on_stack() take the callback function
pointer as argument and initialize the timer completely.

Replace the hrtimer_init*() variants and the open coded initialization of
hrtimer::function with the new setup mechanism.

Switch to use the new functions.

Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: John Stultz <jstultz@google.com>
---
 kernel/time/alarmtimer.c | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 452d8aa2f6e0..f581868e1b3e 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -337,7 +337,6 @@ __alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 	     enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
 {
 	timerqueue_init(&alarm->node);
-	alarm->timer.function = alarmtimer_fired;
 	alarm->function = function;
 	alarm->type = type;
 	alarm->state = ALARMTIMER_STATE_INACTIVE;
@@ -352,8 +351,8 @@ __alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 void alarm_init(struct alarm *alarm, enum alarmtimer_type type,
 		enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
 {
-	hrtimer_init(&alarm->timer, alarm_bases[type].base_clockid,
-		     HRTIMER_MODE_ABS);
+	hrtimer_setup(&alarm->timer, alarmtimer_fired, alarm_bases[type].base_clockid,
+		      HRTIMER_MODE_ABS);
 	__alarm_init(alarm, type, function);
 }
 EXPORT_SYMBOL_GPL(alarm_init);
@@ -816,8 +815,8 @@ static void
 alarm_init_on_stack(struct alarm *alarm, enum alarmtimer_type type,
 		    enum alarmtimer_restart (*function)(struct alarm *, ktime_t))
 {
-	hrtimer_init_on_stack(&alarm->timer, alarm_bases[type].base_clockid,
-			      HRTIMER_MODE_ABS);
+	hrtimer_setup_on_stack(&alarm->timer, alarmtimer_fired, alarm_bases[type].base_clockid,
+			       HRTIMER_MODE_ABS);
 	__alarm_init(alarm, type, function);
 }
 
-- 
2.39.5

[RESEND PATCH v2 19/19] hrtimers: Delete hrtimer_init_on_stack()

[Nam Cao]

hrtimer_init_on_stack() is now unused. Delete it.

Signed-off-by: Nam Cao <namcao@linutronix.de>
---
 include/linux/hrtimer.h |  2 --
 kernel/time/hrtimer.c   | 17 -----------------
 2 files changed, 19 deletions(-)

diff --git a/include/linux/hrtimer.h b/include/linux/hrtimer.h
index 4e4f04b3c0c2..7ef5f7ef31a9 100644
--- a/include/linux/hrtimer.h
+++ b/include/linux/hrtimer.h
@@ -230,8 +230,6 @@ extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock,
 			 enum hrtimer_mode mode);
 extern void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struct hrtimer *),
 			  clockid_t clock_id, enum hrtimer_mode mode);
-extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock,
-				  enum hrtimer_mode mode);
 extern void hrtimer_setup_on_stack(struct hrtimer *timer,
 				   enum hrtimer_restart (*function)(struct hrtimer *),
 				   clockid_t clock_id, enum hrtimer_mode mode);
diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 376b8182b72e..55e9ffbcd49a 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1629,23 +1629,6 @@ void hrtimer_setup(struct hrtimer *timer, enum hrtimer_restart (*function)(struc
 }
 EXPORT_SYMBOL_GPL(hrtimer_setup);
 
-/**
- * hrtimer_init_on_stack - initialize a timer in stack memory
- * @timer:	The timer to be initialized
- * @clock_id:	The clock to be used
- * @mode:       The timer mode
- *
- * Similar to hrtimer_init(), except that this one must be used if struct hrtimer is in stack
- * memory.
- */
-void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t clock_id,
-			   enum hrtimer_mode mode)
-{
-	debug_init_on_stack(timer, clock_id, mode);
-	__hrtimer_init(timer, clock_id, mode);
-}
-EXPORT_SYMBOL_GPL(hrtimer_init_on_stack);
-
 /**
  * hrtimer_setup_on_stack - initialize a timer on stack memory
  * @timer:	The timer to be initialized
-- 
2.39.5

✗ Fi.CI.BUILD: failure for hrtimers: Consolidate hrtimer initialization - Part 1 (rev2)

[Patchwork]

== Series Details ==

Series: hrtimers: Consolidate hrtimer initialization - Part 1 (rev2)
URL   : https://patchwork.freedesktop.org/series/140806/
State : failure

== Summary ==

Error: patch https://patchwork.freedesktop.org/api/1.0/series/140806/revisions/2/mbox/ not applied
Applying: hrtimers: Add missing hrtimer_init() trace points
Applying: drm/i915/request: Remove unnecessary modification of hrtimer::function
Applying: KVM: x86/xen: Initialize hrtimer in kvm_xen_init_vcpu()
Applying: wifi: rt2x00: Remove redundant hrtimer_init()
Applying: io_uring: Remove redundant hrtimer's callback function setup
Applying: hrtimers: Introduce hrtimer_setup() to replace hrtimer_init()
Applying: hrtimers: Introduce hrtimer_setup_on_stack()
Applying: hrtimers: Introduce hrtimer_setup_sleeper_on_stack()
Applying: hrtimers: Introduce hrtimer_update_function()
Applying: fs/aio: Switch to use hrtimer_setup_sleeper_on_stack()
Applying: futex: Switch to use hrtimer_setup_sleeper_on_stack()
Applying: net: pktgen: Switch to use hrtimer_setup_sleeper_on_stack()
Applying: timers: Switch to use hrtimer_setup_sleeper_on_stack()
error: sha1 information is lacking or useless (kernel/time/hrtimer.c).
error: could not build fake ancestor
hint: Use 'git am --show-current-patch=diff' to see the failed patch
Patch failed at 0013 timers: Switch to use hrtimer_setup_sleeper_on_stack()
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".
Build failed, no error log produced