Commit d1c2f1a2 authored by Sebastian Andrzej Siewior's avatar Sebastian Andrzej Siewior Committed by Daniel Wagner

posix-timers: move the rcu head out of the union

On RT the timer can be preempted while running and therefore we wait
with timer_wait_for_callback() for the timer to complete (instead of
busy looping). The RCU-readlock is held to ensure that this posix timer
is not removed while we wait on it.
If the timer is removed then it invokes call_rcu() with a pointer that
is shared with the hrtimer because it is part of the same union.
In order to avoid any possible side effects I am moving the rcu pointer
out of the union.

Cc: [email protected]
Signed-off-by: default avatarSebastian Andrzej Siewior <[email protected]>
Signed-off-by: default avatarDaniel Wagner <[email protected]>
parent 5f6bc51e
......@@ -92,8 +92,8 @@ struct k_itimer {
struct alarm alarmtimer;
ktime_t interval;
} alarm;
struct rcu_head rcu;
} it;
struct rcu_head rcu;
};
struct k_clock {
......
......@@ -567,7 +567,7 @@ static struct k_itimer * alloc_posix_timer(void)
static void k_itimer_rcu_free(struct rcu_head *head)
{
struct k_itimer *tmr = container_of(head, struct k_itimer, it.rcu);
struct k_itimer *tmr = container_of(head, struct k_itimer, rcu);
kmem_cache_free(posix_timers_cache, tmr);
}
......@@ -584,7 +584,7 @@ static void release_posix_timer(struct k_itimer *tmr, int it_id_set)
}
put_pid(tmr->it_pid);
sigqueue_free(tmr->sigq);
call_rcu(&tmr->it.rcu, k_itimer_rcu_free);
call_rcu(&tmr->rcu, k_itimer_rcu_free);
}
static struct k_clock *clockid_to_kclock(const clockid_t id)
......
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