diff options
Diffstat (limited to 'Documentation/admin-guide/pm')
| -rw-r--r-- | Documentation/admin-guide/pm/intel_pstate.rst | 18 | ||||
| -rw-r--r-- | Documentation/admin-guide/pm/sleep-states.rst | 2 |
2 files changed, 15 insertions, 5 deletions
diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index d2b6fda3d67b..8f1d3de449b5 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -145,7 +145,7 @@ feature enabled.] In this mode ``intel_pstate`` registers utilization update callbacks with the CPU scheduler in order to run a P-state selection algorithm, either -``powersave`` or ``performance``, depending on the ``scaling_cur_freq`` policy +``powersave`` or ``performance``, depending on the ``scaling_governor`` policy setting in ``sysfs``. The current CPU frequency information to be made available from the ``scaling_cur_freq`` policy attribute in ``sysfs`` is periodically updated by those utilization update callbacks too. @@ -324,8 +324,7 @@ Global Attributes ``intel_pstate`` exposes several global attributes (files) in ``sysfs`` to control its functionality at the system level. They are located in the -``/sys/devices/system/cpu/cpufreq/intel_pstate/`` directory and affect all -CPUs. +``/sys/devices/system/cpu/intel_pstate/`` directory and affect all CPUs. Some of them are not present if the ``intel_pstate=per_cpu_perf_limits`` argument is passed to the kernel in the command line. @@ -379,6 +378,17 @@ argument is passed to the kernel in the command line. but it affects the maximum possible value of per-policy P-state limits (see `Interpretation of Policy Attributes`_ below for details). +``hwp_dynamic_boost`` + This attribute is only present if ``intel_pstate`` works in the + `active mode with the HWP feature enabled <Active Mode With HWP_>`_ in + the processor. If set (equal to 1), it causes the minimum P-state limit + to be increased dynamically for a short time whenever a task previously + waiting on I/O is selected to run on a given logical CPU (the purpose + of this mechanism is to improve performance). + + This setting has no effect on logical CPUs whose minimum P-state limit + is directly set to the highest non-turbo P-state or above it. + .. _status_attr: ``status`` @@ -410,7 +420,7 @@ argument is passed to the kernel in the command line. That only is supported in some configurations, though (for example, if the `HWP feature is enabled in the processor <Active Mode With HWP_>`_, the operation mode of the driver cannot be changed), and if it is not - supported in the current configuration, writes to this attribute with + supported in the current configuration, writes to this attribute will fail with an appropriate error. Interpretation of Policy Attributes diff --git a/Documentation/admin-guide/pm/sleep-states.rst b/Documentation/admin-guide/pm/sleep-states.rst index 1e5c0f00cb2f..dbf5acd49f35 100644 --- a/Documentation/admin-guide/pm/sleep-states.rst +++ b/Documentation/admin-guide/pm/sleep-states.rst @@ -15,7 +15,7 @@ Sleep States That Can Be Supported ================================== Depending on its configuration and the capabilities of the platform it runs on, -the Linux kernel can support up to four system sleep states, includig +the Linux kernel can support up to four system sleep states, including hibernation and up to three variants of system suspend. The sleep states that can be supported by the kernel are listed below. |