Re: [PATCH 4/4] ARM: timer-sp: Set dynamic irq affinity

From: Santosh Shilimkar
Date: Wed Feb 27 2013 - 00:03:13 EST

On Wednesday 27 February 2013 10:29 AM, Viresh Kumar wrote:
On 27 February 2013 10:26, Santosh Shilimkar <santosh.shilimkar@xxxxxx> wrote:
On Wednesday 27 February 2013 03:47 AM, Daniel Lezcano wrote:

From: Viresh Kumar <viresh.kumar@xxxxxxxxxx>

When a cpu goes to a deep idle state where its local timer is shutdown, it
notifies the time frame work to use the broadcast timer instead.

Unfortunately, the broadcast device could wake up any CPU, including an
idle one
which is not concerned by the wake up at all.

Broad-cast device will only open the CPU for which the timer IRQ
affined to. And infact with subject series the affinity also is
updated for the CPU which owns the last timer expiry event.

What am I missing here ?

Dynamic affinity will work only if the following flag is set for a
clock_event_device: CLOCK_EVT_FEAT_DYNIRQ, otherwise wakeup
would happen on the cpu to which static affinity was set to.

I should have looked at the patches in order first :)
Sorry for the noise.

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