Re: [PATCH v4 0/5] Refactor thermal pressure update to avoid code duplication

From: Lukasz Luba
Date: Tue Nov 23 2021 - 04:46:13 EST

On 11/23/21 9:45 AM, Viresh Kumar wrote:
On 09-11-21, 19:57, Lukasz Luba wrote:
Hi all,

This patch set v4 aims to refactor the thermal pressure update
code. There are already two clients which do similar thing:
convert the capped frequency value into the capacity of
affected CPU and call the 'set' function to store the
reduced capacity into the per-cpu variable.
There might be more than two of these users. In near future
it will be scmi-cpufreq driver, which receives notification
from FW about reduced frequency due to thermal. Other vendors
might follow. Let's avoid code duplication and potential
conversion bugs. Move the conversion code into the arch_topology.c
where the capacity calculation setup code and thermal pressure sit.

Apart from that $subject patches, there is one patch (3/5) which fixes
issue in qcom-cpufreq-hw.c when the thermal pressure is not
updated for offline CPUs. It's similar fix that has been merged
recently for cpufreq_cooling.c:

The patch 4/5 fixes also qcom-cpufreq-hw.c driver code which did
the translation from frequency to capacity wrongly when there
was a boost frequency available and stored in 'policy->cpuinfo.max_freq'.

- remove the warning when boost frequency is passed and set thermal
pressure to 0 in that case, which means the capping is totally removed
(issue reported by Steev)
- remove the check from patch 4/5 with
'throttled_freq > policy->cpuinfo.max_freq' since it doesn't have
effect; instead relay on new arch_update_thermal_pressure() handling
correctly such use case; this would also fix an issue in that original
driver code, where the reduced capacity was calculated wrongly due
to 'policy->cpuinfo.max_freq' used as a divider
- adjusted comments stressing the fact that the boost frequencies are

Lukasz Luba (5):
arch_topology: Introduce thermal pressure update function
thermal: cpufreq_cooling: Use new thermal pressure update function
cpufreq: qcom-cpufreq-hw: Update offline CPUs per-cpu thermal pressure
cpufreq: qcom-cpufreq-hw: Use new thermal pressure update function
arch_topology: Remove unused topology_set_thermal_pressure() and

arch/arm/include/asm/topology.h | 2 +-
arch/arm64/include/asm/topology.h | 2 +-
drivers/base/arch_topology.c | 42 ++++++++++++++++++++++++++++---
drivers/cpufreq/qcom-cpufreq-hw.c | 14 +++--------
drivers/thermal/cpufreq_cooling.c | 6 +----
include/linux/arch_topology.h | 4 +--
include/linux/sched/topology.h | 6 ++---
init/Kconfig | 2 +-
8 files changed, 50 insertions(+), 28 deletions(-)

Applied. Thanks.

Thank you!