[PATCH 0/2] Save cpuhp dynamic state

Pierre Gondois pierre.gondois at arm.com
Wed Sep 14 09:28:13 PDT 2022


Requesting a CPUHP_AP_ONLINE_DYN cpuhp state reserves a state
among the range [CPUHP_AP_ONLINE_DYN:CPUHP_AP_ONLINE_DYN_END].
The reserved state must be saved in order to remove it later.

Cf. __cpuhp_setup_state_cpuslocked() documentation:
Return:
  On success:
    Positive state number if @state is CPUHP_AP_ONLINE_DYN;
    0 for all other states

Indeed, the following:
  cpuhp_remove_state(CPUHP_AP_ONLINE_DYN);
removes the first dynamic states added to the cpuhp state machine.

Patches were tested as:
- powercap/drivers/dtpm: on a Juno-r2, using a late_initcall()
  to init and exit the dtpm framework.
- driver: soc: xilinx: the patch was only compile tested
  due to missing hardware.

Pierre Gondois (2):
  driver: soc: xilinx: Save cpuhp dynamic state
  powercap/drivers/dtpm: Save cpuhp dynamic state

 drivers/powercap/dtpm_cpu.c             |  7 ++++++-
 drivers/soc/xilinx/xlnx_event_manager.c | 12 ++++++++++--
 2 files changed, 16 insertions(+), 3 deletions(-)

-- 
2.25.1




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