Re: [PATCH] Re: Runaway cron task on 2.5.63/4 bk?

[Andrew Morton <akpm@digeo.com>]

george anzinger <george@mvista.com> wrote:
>
> Ok, here is what I have.  I changed nano sleep to use a local 64-bit
> value for the target expire time in jiffies.  As much as MAX-INT/2-1
> will be put in the timer at any one time. It loops till the target
> time is met or exceeded.  The changes affect (clock)nanosleep only and
> not timers (they still error out for large values).

Seem sane.

> I now use the simple u64=(long long) a * b for the mpy so I have 
> dropped the sc_math.h stuff (I will bring that round again :).

Resistance shall be unflagging!

> What do you think?

Sorry, but this little bit:

	while ((active = del_timer_sync(&new_timer) || 
		rq_time > get_jiffies_64()) &&
 	       !test_thread_flag(TIF_SIGPENDING));
 

 	if (abs_struct.list.next) {
 		spin_lock_irq(&nanosleep_abs_list_lock);
 		list_del(&abs_struct.list);
 		spin_unlock_irq(&nanosleep_abs_list_lock);
 	}
 	if (active) {

should be dragged out and mercifully shot.  Is it possible to make that while
loop a little clearer?

The abs_list exactly duplicates the kernel's existing waitqueue
functionality.  You can use prepare_to_wait()/finish_wait() there.

posix_timers_id, posix_clocks[], nanosleep_abs_list_lock and
nanosleep_abs_list should be static to posix-timers.c.