On Monday, July 27, 2015 08:09:35 PM Viresh Kumar wrote:

On 27-07-15, 15:45, Rafael J. Wysocki wrote:

quoted

Say the subsys add callback runs for a CPU and it doesn't have a policy.
If it is offline, we ignore it and the add callback won't be executed
for it again.

In turn, if it is online, we create a policy for it and we should (right
away) link the policy to all of the CPUs that were offline when the subsys add
callback was called for them.  That's what we do today.

Is there anything missing in that?

So the code is working properly after your patch, but I was talking
on the lines of what Russell suggested.

We should play with the links only when we receive add-dev/remove-dev
from subsys callbacks. The exception to that will be the offline CPUs
for which add-dev is called before their policy existed.

The rule is supposed to be "all of the present CPUs which do not own
a policy should point to one, unless it doesn't exist".  The right
approach is then to create links from them to a policy object as soon
as we create one for them.  Waiting for something else to happen is just
pointless and this approach covers both the offline and online CPUs, so
I don't think that changing it would improve things really.

Thanks,
Rafael