Messages in this thread | | | Date | Mon, 27 Dec 2010 21:12:50 +0800 | Subject | Re: [PATCH] fix unsafe operation in high resolution timer | From | Hillf Danton <> |
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On Sun, Dec 26, 2010 at 9:12 PM, Yong Zhang <yong.zhang0@gmail.com> wrote: > On Sat, Dec 25, 2010 at 10:19:11PM +0800, Hillf Danton wrote: >> > But for a hrtimer which is not free in its callback, like a >> > static defined one. the hrtimer could be referenced at the same >> > time. So here you cann't just delete the two lines. >> >> After callback, as you agree, it is hard to determine in the current >> implementation if the hrtimer is static defined, though another bit >> could be added, say, in the flag word of hrtimer > > Yeah, that is an option, like a flag FREE_IN_CALLBACK/ONESHOT which > indicate that. Or just let the callback return another value like
The result of callback sounds fine. Hillf
> HRTIMER_FREED. But as I said before I'm not sure what's the best way > to fix that. And maybe there's more suitable method. > > BTW, is there any user who free the hrtimer in its callback? > >> , so cutting the two >> lines off is deserved. >> And more, who will take care of the NORESTART again after callback? > > It's not related to NORESTART, just HRTIMER_STATE_CALLBACK. > hrtimer'strategy somehow depends on HRTIMER_STATE_CALLBACK. > You can take a look at the caller of hrtimer_callback_running(). > > Thanks, > Yong >
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