Re: Wait for two clock ticks

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I implemented a timer that can operate without interrupts. but it
relies on smp or smt.
what do you need it for ?

On Fri, Mar 6, 2009 at 5:08 PM, Greg Freemyer <greg.freemyer@xxxxxxxxx> wrote:
> On Fri, Mar 6, 2009 at 9:59 AM, Asim <linkasim@xxxxxxxxx> wrote:
>> Yes - Actually I need to wait for a device to finish something after
>> which I(device) error out. Ideally, I would like a simple
>> function using the standard apis that works on most kernels. I cannot
>> use jiffies as I mentioned earlier. Still working on it.
>>
>> -Asim
>
> In general the idea of waiting 2 whole ticks with interrupts disabled
> is such a bad idea that I don't think you will find a pre-existing API
> to do that.
>
> You definitely will not be able to simply check a variable because
> with interrupts disabled, their is no one to update the variable.
>
> If you really need this, you will likely need a call into a routine
> the gets the current time from a hardware clock.
>
> IMHO, such misbehaving code will never get into mainline and is not
> even a good learning experience.
>
> Greg
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