[PATCH 0/5] Rework system pressure interface to the scheduler

Lukasz Luba lukasz.luba at arm.com
Thu Dec 14 00:22:10 PST 2023


Hi Vincent,

I've been waiting for this feature, thanks!


On 12/12/23 14:27, Vincent Guittot wrote:
> Following the consolidation and cleanup of CPU capacity in [1], this serie
> reworks how the scheduler gets the pressures on CPUs. We need to take into
> account all pressures applied by cpufreq on the compute capacity of a CPU
> for dozens of ms or more and not only cpufreq cooling device or HW
> mitigiations. we split the pressure applied on CPU's capacity in 2 parts:
> - one from cpufreq and freq_qos
> - one from HW high freq mitigiation.
> 
> The next step will be to add a dedicated interface for long standing
> capping of the CPU capacity (i.e. for seconds or more) like the
> scaling_max_freq of cpufreq sysfs. The latter is already taken into
> account by this serie but as a temporary pressure which is not always the
> best choice when we know that it will happen for seconds or more.
> 
> [1] https://lore.kernel.org/lkml/20231211104855.558096-1-vincent.guittot@linaro.org/
> 
> Vincent Guittot (4):
>    cpufreq: Add a cpufreq pressure feedback for the scheduler
>    sched: Take cpufreq feedback into account
>    thermal/cpufreq: Remove arch_update_thermal_pressure()
>    sched: Rename arch_update_thermal_pressure into
>      arch_update_hw_pressure
> 
>   arch/arm/include/asm/topology.h               |  6 +--
>   arch/arm64/include/asm/topology.h             |  6 +--
>   drivers/base/arch_topology.c                  | 26 ++++-----
>   drivers/cpufreq/cpufreq.c                     | 48 +++++++++++++++++
>   drivers/cpufreq/qcom-cpufreq-hw.c             |  4 +-
>   drivers/thermal/cpufreq_cooling.c             |  3 --
>   include/linux/arch_topology.h                 |  8 +--
>   include/linux/cpufreq.h                       | 10 ++++
>   include/linux/sched/topology.h                |  8 +--
>   .../{thermal_pressure.h => hw_pressure.h}     | 14 ++---
>   include/trace/events/sched.h                  |  2 +-
>   init/Kconfig                                  | 12 ++---
>   kernel/sched/core.c                           |  8 +--
>   kernel/sched/fair.c                           | 53 ++++++++++---------
>   kernel/sched/pelt.c                           | 18 +++----
>   kernel/sched/pelt.h                           | 16 +++---
>   kernel/sched/sched.h                          |  4 +-
>   17 files changed, 152 insertions(+), 94 deletions(-)
>   rename include/trace/events/{thermal_pressure.h => hw_pressure.h} (55%)
> 

I would like to test it, but something worries me. Why there is 0/5 in
this subject and only 4 patches?

Could you tell me your base branch that I can apply this, please?

Regards,
Lukasz



More information about the linux-arm-kernel mailing list