Read this:

http://lwn.net/Articles/296578/

Take note there are several apis available:

schedule_hrtimeout, schedule_hrtimeout_range, schedule_timeout,
schedule_timeout_range, schedule_timeout_uninterruptible etc.

On Mon, Feb 20, 2012 at 7:50 AM, Peter Teoh [off-list ref] wrote:

On Wed, Feb 15, 2012 at 12:06 AM, Vimal [off-list ref] wrote:

quoted

Hi all,

Is there a way to set the affinity of hrtimer callback, so that it
executes on a particular logical CPU?

quoted

The reason is that I have a hrtimer callback that executes a tasklet.

 If the timer callback executes on a different CPU than the one it was

quoted

enqueued in, then the tasklet is scheduled on the same CPU, which
makes it difficult to reason serialising locks to per-CPU data

How about this:

http://www.makelinux.net/ldd3/chp-7-sect-5

Tasklet is executed and scheduled on a particular known cpu,  so unless u
spawn another tasklet that execute on the other CPU, u don't need per-CPU
data structure - simply because there is no another CPU to contend with the
data structure.   Not sure if I got the point?

I am not sure why u need to synchronize stuff "between CPU", as a
particular tasklet is only executed on only one CPU at a time:

I suspect what u wanted is a "task".   A tasklet is effectively a "bottom
half" and u are holding a spinlock while executing it, and thus it really
has to be very fast.   Read this paper:

http://www.wil.cx/matthew/lca2003/paper.pdf


structures.

quoted

Any ideas?

Thanks,
--
Vimal

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--
Regards,
Peter Teoh

-- 
Regards,
Peter Teoh
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