[PATCH 0/2] powercap: idle_inject: Create threads on demand

[Andrew Morton]

On Thu, 5 Nov 2026 19:46:13 +0100 Daniel Lezcano <daniel.lezcano at oss.qualcomm.com> wrote:

> On 11/3/26 00:09, Daniel Lezcano wrote:
> > Idle injection currently registers per-CPU kernel threads during early
> > initialization, including on CPUs for which no idle injection device
> > will be registered.
> > 
> > This series makes thread creation follow the lifetime and CPU mask of
> > each idle injection device.
> > 
> > The first patch adds an optional CPU mask to smpboot thread descriptors.
> > The mask restricts thread creation, CPU hotplug handling and teardown,
> > while preserving the existing behavior for descriptors without a mask.
> > 
> > The second patch uses this support to register idle injection threads
> > when a device registers and destroy them when it unregisters. CPU
> > ownership claims, registration rollback and thread teardown are
> > serialized to prevent overlapping registrations from sharing threads.
> > 
> > Validation includes W=1 builds of the affected objects, whitespace
> > checks and static review of the teardown locking paths. Concurrent
> > registration and CPU hotplug runtime testing remains outstanding.
> > 
> > The series was tested on Rockchip RK3588.
> 
> One thing not specified in this cover is which tree these changes have 
> to go through ?

I'd volunteer Rafael's, after peterz/tglx review.

Please!  Removing one kernel thread per cpu makes the world a better
place.