Re: [patch] del_timer_sync scalability patch

[Oleg Nesterov]

Christoph Lameter wrote:
>
> On Sun, 13 Mar 2005, Oleg Nesterov wrote:
>
> > I suspect that del_timer_sync() in its current form is racy.
> >
...snip...
> > next timer interrupt, __run_timers() picks
> > this timer again, sets timer->base = NULL
                      ^^^^^^^^^^^^^^^^^^^^^^^
> >
> > 						if (timer_pending(timer))	// no, timer->base == NULL
>
> timer->base is != NULL because the timer has rescheduled itself.
> __mod_timer sets timer->bBase

Christoph, please look again. Yes, __mod_timer sets timer->base,
but it is cleared in the _next_ timer interrupt on CPU 0.

Andrew, Ingo, what do you think?

Oleg.
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