0258cb19c7
Thermal pressure provides a new API, which allows to use CPU frequency as an argument. That removes the need of local conversion to capacity. Use this new API and remove old local conversion code. The new arch_update_thermal_pressure() also accepts boost frequencies, which solves issue in the driver code with wrong reduced capacity calculation. The reduced capacity was calculated wrongly due to 'policy->cpuinfo.max_freq' used as a divider. The value present there was actually the boost frequency. Thus, even a normal maximum frequency value which corresponds to max CPU capacity (arch_scale_cpu_capacity(cpu_id)) is not able to remove the capping. The second side effect which is solved is that the reduced frequency wasn't properly translated into the right reduced capacity, e.g. boost frequency = 3000MHz (stored in policy->cpuinfo.max_freq) max normal frequency = 2500MHz (which is 1024 capacity) 2nd highest frequency = 2000MHz (which translates to 819 capacity) Then in a scenario when the 'throttled_freq' max allowed frequency was 2000MHz the driver translated it into 682 capacity: capacity = 1024 * 2000 / 3000 = 682 Then set the pressure value bigger than actually applied by the HW: max_capacity - capacity => 1024 - 682 = 342 (<- thermal pressure) Which was causing higher throttling and misleading task scheduler about available CPU capacity. A proper calculation in such case should be: capacity = 1024 * 2000 / 2500 = 819 1024 - 819 = 205 (<- thermal pressure) This patch relies on the new arch_update_thermal_pressure() handling correctly such use case (with boost frequencies). Signed-off-by: Lukasz Luba <lukasz.luba@arm.com> Reviewed-by: Thara Gopinath <thara.gopinath@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.