On 09/27, Waiman Long wrote:
>
> +static inline int sigequalsets(const sigset_t *set1, const sigset_t *set2)
> +{
> + switch (_NSIG_WORDS) {
> + case 4:
> + return (set1->sig[3] == set2->sig[3]) &&
> + (set1->sig[2] == set2->sig[2]) &&
> + (set1->sig[1] == set2->sig[1]) &&
> + (set1->sig[0] == set2->sig[0]);
> + case 2:
> + return (set1->sig[1] == set2->sig[1]) &&
> + (set1->sig[0] == set2->sig[0]);
> + case 1:
> + return set1->sig[0] == set2->sig[0];
> + }
> + return 0;
> +}
> +
OK, this memcmp-by-hand matches other sig* helpers. Well, perhaps
default:
BUILD_BUG();
makes sense too, but I won't insist.
> --- a/kernel/signal.c
> +++ b/kernel/signal.c
> @@ -2485,6 +2485,13 @@ void __set_current_blocked(const sigset_t *newset)
> {
> struct task_struct *tsk = current;
>
> + /*
> + * In case the signal mask hasn't changed, there is nothing we need
> + * to do. The current->blocked shouldn't be modified by other task.
> + */
> + if (sigequalsets(&tsk->blocked, newset))
> + return;
> +
Acked-by: Oleg Nesterov <[email protected]>
