Merge tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer cleanups from Thomas Gleixner:
 "A treewide hrtimer timer cleanup

  hrtimers are initialized with hrtimer_init() and a subsequent store to
  the callback pointer. This turned out to be suboptimal for the
  upcoming Rust integration and is obviously a silly implementation to
  begin with.

  This cleanup replaces the hrtimer_init(T); T->function = cb; sequence
  with hrtimer_setup(T, cb);

  The conversion was done with Coccinelle and a few manual fixups.

  Once the conversion has completely landed in mainline, hrtimer_init()
  will be removed and the hrtimer::function becomes a private member"

* tag 'timers-cleanups-2025-03-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (100 commits)
  wifi: rt2x00: Switch to use hrtimer_update_function()
  io_uring: Use helper function hrtimer_update_function()
  serial: xilinx_uartps: Use helper function hrtimer_update_function()
  ASoC: fsl: imx-pcm-fiq: Switch to use hrtimer_setup()
  RDMA: Switch to use hrtimer_setup()
  virtio: mem: Switch to use hrtimer_setup()
  drm/vmwgfx: Switch to use hrtimer_setup()
  drm/xe/oa: Switch to use hrtimer_setup()
  drm/vkms: Switch to use hrtimer_setup()
  drm/msm: Switch to use hrtimer_setup()
  drm/i915/request: Switch to use hrtimer_setup()
  drm/i915/uncore: Switch to use hrtimer_setup()
  drm/i915/pmu: Switch to use hrtimer_setup()
  drm/i915/perf: Switch to use hrtimer_setup()
  drm/i915/gvt: Switch to use hrtimer_setup()
  drm/i915/huc: Switch to use hrtimer_setup()
  drm/amdgpu: Switch to use hrtimer_setup()
  stm class: heartbeat: Switch to use hrtimer_setup()
  i2c: Switch to use hrtimer_setup()
  iio: Switch to use hrtimer_setup()
  ...

6 files changed, 8 insertions, 19 deletions

diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c
index 453dc76c9348..22376a1a75b9 100644
--- a/kernel/time/hrtimer.c
+++ b/kernel/time/hrtimer.c
@@ -1592,11 +1592,6 @@ static inline int hrtimer_clockid_to_base(clockid_t clock_id)
 	}
 }
 
-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)
 {
diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index 163e7a2033b6..b837d3d9d325 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -678,8 +678,7 @@ void ntp_notify_cmos_timer(bool offset_set)
 
 static void __init ntp_init_cmos_sync(void)
 {
-	hrtimer_init(&sync_hrtimer, CLOCK_REALTIME, HRTIMER_MODE_ABS);
-	sync_hrtimer.function = sync_timer_callback;
+	hrtimer_setup(&sync_hrtimer, sync_timer_callback, CLOCK_REALTIME, HRTIMER_MODE_ABS);
 }
 #else /* CONFIG_GENERIC_CMOS_UPDATE) || defined(CONFIG_RTC_SYSTOHC) */
 static inline void __init ntp_init_cmos_sync(void) { }
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index bc0bdf40eb50..6222112533a7 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -466,7 +466,7 @@ static void posix_timer_unhash_and_free(struct k_itimer *tmr)
 
 static int common_timer_create(struct k_itimer *new_timer)
 {
-	hrtimer_init(&new_timer->it.real.timer, new_timer->it_clock, 0);
+	hrtimer_setup(&new_timer->it.real.timer, posix_timer_fn, new_timer->it_clock, 0);
 	return 0;
 }
 
@@ -821,7 +821,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
 	/*
 	 * Posix magic: Relative CLOCK_REALTIME timers are not affected by
 	 * clock modifications, so they become CLOCK_MONOTONIC based under the
-	 * hood. See hrtimer_init(). Update timr->kclock, so the generic
+	 * hood. See hrtimer_setup(). Update timr->kclock, so the generic
 	 * functions which use timr->kclock->clock_get_*() work.
 	 *
 	 * Note: it_clock stays unmodified, because the next timer_set() might
@@ -830,8 +830,7 @@ static void common_hrtimer_arm(struct k_itimer *timr, ktime_t expires,
 	if (timr->it_clock == CLOCK_REALTIME)
 		timr->kclock = absolute ? &clock_realtime : &clock_monotonic;
 
-	hrtimer_init(&timr->it.real.timer, timr->it_clock, mode);
-	timr->it.real.timer.function = posix_timer_fn;
+	hrtimer_setup(&timr->it.real.timer, posix_timer_fn, timr->it_clock, mode);
 
 	if (!absolute)
 		expires = ktime_add_safe(expires, timer->base->get_time());
diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index fcca4e72f1ef..cc15fe293719 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -263,8 +263,7 @@ void __init generic_sched_clock_init(void)
 	 * Start the timer to keep sched_clock() properly updated and
 	 * sets the initial epoch.
 	 */
-	hrtimer_init(&sched_clock_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
-	sched_clock_timer.function = sched_clock_poll;
+	hrtimer_setup(&sched_clock_timer, sched_clock_poll, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL_HARD);
 }
 
diff --git a/kernel/time/tick-broadcast-hrtimer.c b/kernel/time/tick-broadcast-hrtimer.c
index e28f9210f8a1..a88b72b0f35e 100644
--- a/kernel/time/tick-broadcast-hrtimer.c
+++ b/kernel/time/tick-broadcast-hrtimer.c
@@ -100,7 +100,6 @@ static enum hrtimer_restart bc_handler(struct hrtimer *t)
 
 void tick_setup_hrtimer_broadcast(void)
 {
-	hrtimer_init(&bctimer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
-	bctimer.function = bc_handler;
+	hrtimer_setup(&bctimer, bc_handler, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 	clockevents_register_device(&ce_broadcast_hrtimer);
 }
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index fa058510af9c..c527b421c865 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -1573,12 +1573,10 @@ void tick_setup_sched_timer(bool hrtimer)
 	struct tick_sched *ts = this_cpu_ptr(&tick_cpu_sched);
 
 	/* Emulate tick processing via per-CPU hrtimers: */
-	hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
+	hrtimer_setup(&ts->sched_timer, tick_nohz_handler, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD);
 
-	if (IS_ENABLED(CONFIG_HIGH_RES_TIMERS) && hrtimer) {
+	if (IS_ENABLED(CONFIG_HIGH_RES_TIMERS) && hrtimer)
 		tick_sched_flag_set(ts, TS_FLAG_HIGHRES);
-		ts->sched_timer.function = tick_nohz_handler;
-	}
 
 	/* Get the next period (per-CPU) */
 	hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update());