Re: [PATCH 00/28] PM: QoS: Get rid of unuseful code and rework CPU latency QoS interface

Rafael J. Wysocki
2020-02-12T09:39:28Z

On Wed, Feb 12, 2020 at 12:39 AM Rafael J. Wysocki <rjw@rjwysocki.net> wrote:
>
> Hi All,
>
> This series of patches is based on the observation that after commit
> c3082a674f46 ("PM: QoS: Get rid of unused flags") the only global PM QoS class
> in use is PM_QOS_CPU_DMA_LATENCY, but there is still a significant amount of
> code dedicated to the handling of global PM QoS classes in general. That code
> takes up space and adds overhead in vain, so it is better to get rid of it.
>
> Moreover, with that unuseful code removed, the interface for adding QoS
> requests for CPU latency becomes inelegant and confusing, so it is better to
> clean it up.
>
> Patches [01/28-12/28] do the first part described above, which also includes
> some assorted cleanups of the core PM QoS code that doesn't go away.
>
> Patches [13/28-25/28] rework the CPU latency QoS interface (in the classic
> "define stubs, migrate users, change the API proper" manner), patches
> [26-27/28] update the general comments and documentation to match the code
> after the previous changes and the last one makes the CPU latency QoS depend
> on CPU_IDLE (because cpuidle is the only user of its target value today).
>
> The majority of the patches in this series don't change the functionality of
> the code at all (at least not intentionally).
>
> Please refer to the changelogs of individual patches for details.
>
> Thanks!

This patch series is available in the git branch at

git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git
cpu-latency-qos

for easier access, but please note that it may be updated in response
to review comments etc.