On 19.05.2025 22:12, dm...@proton.me wrote:
> From: Denis Mukhin <dmuk...@ford.com>
>
> The physical console input rotation depends on max_init_domid symbol, which is
> managed differently across architectures.
>
> Instead of trying to manage max_init_domid in the arch-common code the console
> input rotation code can be reworked by removing dependency on max_init_domid
> entirely.
... at the expense of doing (worst case) 32k iterations just to find nothing
(else). Iirc it was to avoid this why max_init_domid was introduced.
> --- a/xen/common/domain.c
> +++ b/xen/common/domain.c
> @@ -2460,6 +2460,35 @@ void domid_free(domid_t domid)
> spin_unlock(&domid_lock);
> }
>
> +/*
> + * Find the ID of the next possible console owner domain.
> + *
> + * @return Domain ID: DOMID_XEN or non-system domain IDs within
> + * the range of [0..CONFIG_MAX_DOMID-1].
> + */
> +domid_t domid_find_with_input_allowed(domid_t hint)
> +{
> + struct domain *d;
const?
> + domid_t domid = DOMID_XEN;
> +
> + spin_lock(&domlist_update_lock);
Why this heavy lock? Other functions iterating the list just use the RCU
read lock.
Jan
