add at24 driver

hc

2023-11-06 15ade055295d13f95d49e3d99b09f3bbfb4a43e7

 kernel/kernel/time/posix-timers.c
..
..
@@ -463,7 +463,7 @@
463
463
 
464
464
 static void k_itimer_rcu_free(struct rcu_head *head)
465
465
 {
466
-	struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
466
+	struct k_itimer *tmr = container_of(head, struct k_itimer, rcu);
467
467
 
468
468
 	kmem_cache_free(posix_timers_cache, tmr);
469
469
 }
..
..
@@ -480,7 +480,7 @@
480
480
 	}
481
481
 	put_pid(tmr->it_pid);
482
482
 	sigqueue_free(tmr->sigq);
483
-	call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
483
+	call_rcu(&tmr->rcu, k_itimer_rcu_free);
484
484
 }
485
485
 
486
486
 static int common_timer_create(struct k_itimer *new_timer)
..
..
@@ -826,6 +826,17 @@
826
826
 	return hrtimer_try_to_cancel(&timr->it.real.timer);
827
827
 }
828
828
 
829
+static void timer_wait_for_callback(const struct k_clock *kc, struct k_itimer *timer)
830
+{
831
+	if (kc->timer_arm == common_hrtimer_arm)
832
+		hrtimer_grab_expiry_lock(&timer->it.real.timer);
833
+	else if (kc == &alarm_clock)
834
+		hrtimer_grab_expiry_lock(&timer->it.alarm.alarmtimer.timer);
835
+	else
836
+		/* posix-cpu-timers */
837
+		cpu_timers_grab_expiry_lock(timer);
838
+}
839
+
829
840
 /* Set a POSIX.1b interval timer. */
830
841
 int common_timer_set(struct k_itimer *timr, int flags,
831
842
 		     struct itimerspec64 *new_setting,
..
..
@@ -891,11 +902,15 @@
891
902
 	else
892
903
 		error = kc->timer_set(timr, flags, new_spec64, old_spec64);
893
904
 
894
-	unlock_timer(timr, flag);
895
905
 	if (error == TIMER_RETRY) {
906
+		rcu_read_lock();
907
+		unlock_timer(timr, flag);
908
+		timer_wait_for_callback(kc, timr);
909
+		rcu_read_unlock();
896
910
 		old_spec64 = NULL;	// We already got the old time...
897
911
 		goto retry;
898
912
 	}
913
+	unlock_timer(timr, flag);
899
914
 
900
915
 	return error;
901
916
 }
..
..
@@ -957,13 +972,21 @@
957
972
 	return 0;
958
973
 }
959
974
 
960
-static inline int timer_delete_hook(struct k_itimer *timer)
975
+static int timer_delete_hook(struct k_itimer *timer)
961
976
 {
962
977
 	const struct k_clock *kc = timer->kclock;
978
+	int ret;
963
979
 
964
980
 	if (WARN_ON_ONCE(!kc || !kc->timer_del))
965
981
 		return -EINVAL;
966
-	return kc->timer_del(timer);
982
+	ret = kc->timer_del(timer);
983
+	if (ret == TIMER_RETRY) {
984
+		rcu_read_lock();
985
+		spin_unlock_irq(&timer->it_lock);
986
+		timer_wait_for_callback(kc, timer);
987
+		rcu_read_unlock();
988
+	}
989
+	return ret;
967
990
 }
968
991
 
969
992
 /* Delete a POSIX.1b interval timer. */
..
..
@@ -977,10 +1000,8 @@
977
1000
 	if (!timer)
978
1001
 		return -EINVAL;
979
1002
 
980
-	if (timer_delete_hook(timer) == TIMER_RETRY) {
981
-		unlock_timer(timer, flags);
1003
+	if (timer_delete_hook(timer) == TIMER_RETRY)
982
1004
 		goto retry_delete;
983
-	}
984
1005
 
985
1006
 	spin_lock(&current->sighand->siglock);
986
1007
 	list_del(&timer->list);
..
..
@@ -1006,10 +1027,9 @@
1006
1027
 retry_delete:
1007
1028
 	spin_lock_irqsave(&timer->it_lock, flags);
1008
1029
 
1009
-	if (timer_delete_hook(timer) == TIMER_RETRY) {
1010
-		unlock_timer(timer, flags);
1030
+	if (timer_delete_hook(timer) == TIMER_RETRY)
1011
1031
 		goto retry_delete;
1012
-	}
1032
+
1013
1033
 	list_del(&timer->list);
1014
1034
 	/*
1015
1035
 	 * This keeps any tasks waiting on the spin lock from thinking