Re: [patch V2 38/38] posix-cpu-timers: Utilize timerqueue for storage

[Frederic Weisbecker <frederic@kernel.org>]

On Wed, Aug 21, 2019 at 09:09:25PM +0200, Thomas Gleixner wrote:
>  /**
> @@ -92,14 +130,10 @@ struct posix_cputimers {
>  
>  static inline void posix_cputimers_init(struct posix_cputimers *pct)
>  {
> -	pct->timers_active = 0;
> -	pct->expiry_active = 0;

No more need to initialize these?

> +	memset(pct->bases, 0, sizeof(pct->bases));
>  	pct->bases[0].nextevt = U64_MAX;
>  	pct->bases[1].nextevt = U64_MAX;
>  	pct->bases[2].nextevt = U64_MAX;
> -	INIT_LIST_HEAD(&pct->bases[0].cpu_timers);
> -	INIT_LIST_HEAD(&pct->bases[1].cpu_timers);
> -	INIT_LIST_HEAD(&pct->bases[2].cpu_timers);
>  }

[...]

> @@ -393,15 +395,15 @@ static int posix_cpu_timer_del(struct k_
>  	sighand = lock_task_sighand(p, &flags);
>  	if (unlikely(sighand == NULL)) {
>  		/*
> -		 * We raced with the reaping of the task.
> -		 * The deletion should have cleared us off the list.
> +		 * This raced with the reaping of the task. The exit cleanup
> +		 * should have removed this timer from the timer queue.
>  		 */
> -		WARN_ON_ONCE(!list_empty(&timer->it.cpu.entry));
> +		WARN_ON_ONCE(ctmr->head || timerqueue_node_queued(&ctmr->node));

Should we clear ctmr->head upon cleanup_timerqueue() ?

Thanks.


>  	} else {
>  		if (timer->it.cpu.firing)
>  			ret = TIMER_RETRY;
>  		else
> -			list_del(&timer->it.cpu.entry);
> +			cpu_timer_dequeue(ctmr);
>  
>  		unlock_task_sighand(p, &flags);
>  	}
> @@ -412,12 +414,12 @@ static int posix_cpu_timer_del(struct k_
>  	return ret;
>  }
>  
> -static void cleanup_timers_list(struct list_head *head)
> +static void cleanup_timerqueue(struct timerqueue_head *head)
>  {
> -	struct cpu_timer_list *timer, *next;
> +	struct timerqueue_node *node;
>  
> -	list_for_each_entry_safe(timer, next, head, entry)
> -		list_del_init(&timer->entry);
> +	while ((node = timerqueue_getnext(head)))
> +		timerqueue_del(head, node);
>  }