On 08/15, Eric W. Biederman wrote:
>
> +#define do_each_pid_task(pid, type, task) \
> + if ((task = pid_task(pid, type))) { \
> + prefetch(pid_next(task, type)); \
> + do {
> +
> +#define while_each_pid_task(pid, type, task) \
> + } while (pid_next(task, type) && ({ \
> + task = pid_next_task(task, type); \
> + rcu_dereference(task); \
> + prefetch(pid_next(task, type)); \
> + 1; }) ); \
> + }
A small nit. Suppose a non-leader thread blocks a signal, and does
exec. There is a window when we have 2 tasks with the same pid in
PIDTYPE_PID namespace. If send_sigio() send the signal in that
window, it will be delivered twice to process.
Oleg.
