Hi Sudeep,

On 2/28/2019 5:49 PM, Sudeep Holla wrote:

On Thu, Feb 28, 2019 at 05:23:58PM +0530, Lingutla Chandrasekhar wrote:

quoted

With commit '5bdd2b3f0f8 ("arm64: topology: add support to remove cpu
topology sibling masks")', when cpu hotplugged out, it resets the cpu
information in its sibling CPUs. If user changes capacity of any cpu,
then the new capacity applied to all online cpus in the cluster.

Correct but you are now changing to apply the same to all the CPUs
in the package which is wrong.

quoted

If any hot plugged out cpu in the same cluster comes back to online,
then that would have different/stale capacity value.

Why not save the value ?

Sorry, didn't get you, you mean save user supplied value ?

quoted

Fix it by applying user supplied capacity to all possible cpus in the
cluster.

NACK for the change. It changes for all the CPUs in the package/socket.
Though DT platforms have cluster ids as package ids, that's wrong and
must be fixed. So you need to fix this issuw without depending on the
package id. I have removed all the wrong users of the same and this is
also a wrong usage.

I presumed all cores with same package-id have same cpu capacity, so depended on it.
I think, we can update the capacity of newly online cpu by reading its core_sibling cpu capacity.
Let me know your opinion on this option ?

--
Regards,
Sudeep

--
Chandrasekhar L,  
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
 a Linux Foundation Collaborative Project.


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