posix-timers: Remove a few paranoid warnings

Warnings about a non-initialized timer or non-existing callbacks are just
useful for implementing new posix clocks, but there a NULL pointer
dereference is expected anyway. :)

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250308155623.765462334@linutronix.de

diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index e908846446a140faf2ce0e658bb61becf9618d73..5591b1589985ceb7eb7c73481eb6c044e0ad76e5 100644 (file)
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -682,7 +682,6 @@ void common_timer_get(struct k_itimer *timr, struct itimerspec64 *cur_setting)
 
 static int do_timer_gettime(timer_t timer_id,  struct itimerspec64 *setting)
 {
-       const struct k_clock *kc;
        struct k_itimer *timr;
        unsigned long flags;
        int ret = 0;
@@ -692,11 +691,7 @@ static int do_timer_gettime(timer_t timer_id,  struct itimerspec64 *setting)
                return -EINVAL;
 
        memset(setting, 0, sizeof(*setting));
-       kc = timr->kclock;
-       if (WARN_ON_ONCE(!kc || !kc->timer_get))
-               ret = -EINVAL;
-       else
-               kc->timer_get(timr, setting);
+       timr->kclock->timer_get(timr, setting);
 
        unlock_timer(timr, flags);
        return ret;
@@ -824,7 +819,6 @@ static void common_timer_wait_running(struct k_itimer *timer)
 static struct k_itimer *timer_wait_running(struct k_itimer *timer,
                                           unsigned long *flags)
 {
-       const struct k_clock *kc = READ_ONCE(timer->kclock);
        timer_t timer_id = READ_ONCE(timer->it_id);
 
        /* Prevent kfree(timer) after dropping the lock */
@@ -835,8 +829,7 @@ static struct k_itimer *timer_wait_running(struct k_itimer *timer,
         * kc->timer_wait_running() might drop RCU lock. So @timer
         * cannot be touched anymore after the function returns!
         */
-       if (!WARN_ON_ONCE(!kc->timer_wait_running))
-               kc->timer_wait_running(timer);
+       timer->kclock->timer_wait_running(timer);
 
        rcu_read_unlock();
        /* Relock the timer. It might be not longer hashed. */
@@ -899,7 +892,6 @@ static int do_timer_settime(timer_t timer_id, int tmr_flags,
                            struct itimerspec64 *new_spec64,
                            struct itimerspec64 *old_spec64)
 {
-       const struct k_clock *kc;
        struct k_itimer *timr;
        unsigned long flags;
        int error;
@@ -922,11 +914,7 @@ retry:
        /* Prevent signal delivery and rearming. */
        timr->it_signal_seq++;
 
-       kc = timr->kclock;
-       if (WARN_ON_ONCE(!kc || !kc->timer_set))
-               error = -EINVAL;
-       else
-               error = kc->timer_set(timr, tmr_flags, new_spec64, old_spec64);
+       error = timr->kclock->timer_set(timr, tmr_flags, new_spec64, old_spec64);
 
        if (error == TIMER_RETRY) {
                // We already got the old time...
@@ -1008,18 +996,6 @@ static inline void posix_timer_cleanup_ignored(struct k_itimer *tmr)
        }
 }
 
-static inline int timer_delete_hook(struct k_itimer *timer)
-{
-       const struct k_clock *kc = timer->kclock;
-
-       /* Prevent signal delivery and rearming. */
-       timer->it_signal_seq++;
-
-       if (WARN_ON_ONCE(!kc || !kc->timer_del))
-               return -EINVAL;
-       return kc->timer_del(timer);
-}
-
 /* Delete a POSIX.1b interval timer. */
 SYSCALL_DEFINE1(timer_delete, timer_t, timer_id)
 {
@@ -1032,7 +1008,10 @@ retry_delete:
        if (!timer)
                return -EINVAL;
 
-       if (unlikely(timer_delete_hook(timer) == TIMER_RETRY)) {
+       /* Prevent signal delivery and rearming. */
+       timer->it_signal_seq++;
+
+       if (unlikely(timer->kclock->timer_del(timer) == TIMER_RETRY)) {
                /* Unlocks and relocks the timer if it still exists */
                timer = timer_wait_running(timer, &flags);
                goto retry_delete;
@@ -1078,7 +1057,7 @@ retry_delete:
         * mechanism. Worse, that timer mechanism might run the expiry
         * function concurrently.
         */
-       if (timer_delete_hook(timer) == TIMER_RETRY) {
+       if (timer->kclock->timer_del(timer) == TIMER_RETRY) {
                /*
                 * Timer is expired concurrently, prevent livelocks
                 * and pointless spinning on RT.