mainlining shenanigans
18734958e9
Modify the intel_idle driver to get the C-states information from ACPI _CST if the processor model is not recognized by it. The processor is still required to support MWAIT and the information from ACPI _CST will only be used if all of the C-states listed by _CST are of the ACPI_CSTATE_FFH type (which means that they are expected to be entered via MWAIT). Moreover, the driver assumes that the _CST information is the same for all CPUs in the system, so it is sufficient to evaluate _CST for one of them and extract the common list of C-states from there. Also _CST is evaluated once at the system initialization time and the driver does not respond to _CST change notifications (that can be changed in the future). The main functional difference between intel_idle with this change and the ACPI processor driver is that the former sets the target residency to be equal to the exit latency (provided by _CST) for C1-type C-states and to 3 times the exit latency value for the other C-state types, whereas the latter obtains the target residency by multiplying the exit latency by the same number (2 by default) for all C-state types. Therefore it is expected that in general using the former instead of the latter on the same system will lead to improved energy-efficiency. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> |
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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.