• Rafael J. Wysocki's avatar
    intel_idle: Introduce 'states_off' module parameter · 4dcb78ee
    Rafael J. Wysocki authored
    In certain system configurations it may not be desirable to use some
    C-states assumed to be available by intel_idle and the driver needs
    to be prevented from using them even before the cpuidle sysfs
    interface becomes accessible to user space.  Currently, the only way
    to achieve that is by setting the 'max_cstate' module parameter to a
    value lower than the index of the shallowest of the C-states in
    question, but that may be overly intrusive, because it effectively
    makes all of the idle states deeper than the 'max_cstate' one go
    away (and the C-state to avoid may be in the middle of the range
    normally regarded as available).
    
    To allow that limitation to be overcome, introduce a new module
    parameter called 'states_off' to represent a list of idle states to
    be disabled by default in the form of a bitmask and update the
    documentation to cover it.
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    4dcb78ee
intel_idle.rst 14.9 KB