An important part of validating that s0ix worked properly is to check how
much of a cycle was spent in a hardware sleep state.
The reporting of hardware sleep is a mix of kernel messages and sysfs
files that vary from vendor to vendor. Collecting this information
requires extra information on the kernel command line or fetching from
debugfs.
To make this information more readily accessible introduce a new file in
suspend_stats that drivers can report into during their resume routine.
Userspace can fetch this information and compare it against the duration
of the cycle to allow determining residency percentages and flagging
problems.
v5->v6
* Add sysfs file for total
* In cases we know overflow return -EOVERFLOW
* Update documentation
* Rename symbol
* Fix kernel robot reported missing stub
Mario Limonciello (4):
PM: Add sysfs files to represent time spent in hardware sleep state
platform/x86/amd: pmc: Report duration of time in hw sleep state
platform/x86/intel/pmc: core: Always capture counters on suspend
platform/x86/intel/pmc: core: Report duration of time in HW sleep
state
Documentation/ABI/testing/sysfs-power | 27 ++++++++++++++++
drivers/platform/x86/amd/pmc.c | 5 ++-
drivers/platform/x86/intel/pmc/core.c | 18 ++++++-----
drivers/platform/x86/intel/pmc/core.h | 2 --
include/linux/suspend.h | 5 +++
kernel/power/main.c | 45 +++++++++++++++++++++++++++
6 files changed, 89 insertions(+), 13 deletions(-)
--
2.34.1
