Hi all,
These are a few trivial patches to populate cpu capacity information
using performance information from ACPI's CPPC.
I've tied this functionality to the existing function
init_freq_invariance_cppc() called in acpi_cppc_processor_probe().
This function is renamed to a more generic arch_init_invariance_cppc().
The patches have been build tested on x86 and more thoroughly tested on
Juno R2 (arm64), which uses the new functionality, with the following
results:
root@ubuntu:~# dmesg | grep cpu_capacity
[ 2.157494] init_cpu_capacity_cppc: CPU0 cpu_capacity=38300 (raw).
[ 2.163699] init_cpu_capacity_cppc: CPU1 cpu_capacity=38300 (raw).
[ 2.169899] init_cpu_capacity_cppc: CPU2 cpu_capacity=38300 (raw).
[ 2.176098] init_cpu_capacity_cppc: CPU3 cpu_capacity=38300 (raw).
[ 2.182296] init_cpu_capacity_cppc: CPU4 cpu_capacity=102400 (raw).
[ 2.188581] init_cpu_capacity_cppc: CPU5 cpu_capacity=102400 (raw).
[ 2.194867] cpu_capacity: capacity_scale=102400
[ 2.199409] cpu_capacity: CPU0 cpu_capacity=383
[ 2.203952] cpu_capacity: CPU1 cpu_capacity=383
[ 2.208495] cpu_capacity: CPU2 cpu_capacity=383
[ 2.213037] cpu_capacity: CPU3 cpu_capacity=383
[ 2.217580] cpu_capacity: CPU4 cpu_capacity=1024
[ 2.222209] cpu_capacity: CPU5 cpu_capacity=1024
[ 2.226886] init_cpu_capacity_cppc: cpu_capacity initialization done
root@ubuntu:~# tail -n +1 /sys/devices/system/cpu/cpu*/cpu_capacity
==> /sys/devices/system/cpu/cpu0/cpu_capacity <==
383
==> /sys/devices/system/cpu/cpu1/cpu_capacity <==
383
==> /sys/devices/system/cpu/cpu2/cpu_capacity <==
383
==> /sys/devices/system/cpu/cpu3/cpu_capacity <==
383
==> /sys/devices/system/cpu/cpu4/cpu_capacity <==
1024
==> /sys/devices/system/cpu/cpu5/cpu_capacity <==
1024
All works as expected even if ACPI processor support is built as a
module.
Patches are based on v5.13-rc1.
Let me know what you think!
Thanks,
Ionela.
Ionela Voinescu (3):
x86, ACPI: rename init_freq_invariance_cppc to
arch_init_invariance_cppc
arch_topology: obtain cpu capacity using information from CPPC
arm64, topology: enable use of init_cpu_capacity_cppc()
arch/arm64/include/asm/topology.h | 4 ++++
arch/x86/include/asm/topology.h | 2 +-
drivers/acpi/cppc_acpi.c | 6 ++---
drivers/base/arch_topology.c | 39 +++++++++++++++++++++++++++++++
include/linux/arch_topology.h | 4 ++++
5 files changed, 51 insertions(+), 4 deletions(-)
--
2.29.2.dirty
