• Oleg Nesterov's avatar
    posix-timers: use "struct pid*" instead of "struct task_struct*" · 27af4245
    Oleg Nesterov authored
    Impact: restructure, clean up code
    k_itimer holds the ref to the ->it_process until sys_timer_delete(). This
    allows to pin up to RLIMIT_SIGPENDING dead task_struct's. Change the code
    to use "struct pid *" instead.
    The patch doesn't kill ->it_process, it places ->it_pid into the union.
    ->it_process is still used by do_cpu_nanosleep() as before. It would be
    trivial to change the nanosleep code as well, but since it uses it_process
    in a special way I think it is better to keep this field for grep.
    The patch bloats the kernel by 104 bytes and it also adds the new pointer,
    ->it_signal, to k_itimer. It is used by lock_timer() to verify that the
    found timer was not created by another process. It is not clear why do we
    use the global database (and thus the global idr_lock) for posix timers.
    We still need the signal_struct->posix_timers which contains all useable
    timers, perhaps it is better to use some form of per-process array
    Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
    Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
    Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
posix-timers.h 4.17 KB