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 <htmldeveloper@gmail.com> wrote:

On Wed, Feb 15, 2012 at 12:06 AM, Vimal <j.vimal@gmail.com> wrote:

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Hi all,

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

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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

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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.

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Any ideas?

Thanks, -- Vimal

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-- Regards, Peter Teoh

-- Regards, Peter Teoh