• Rafael J. Wysocki's avatar
    cpufreq / sched: SCHED_CPUFREQ_IOWAIT flag to indicate iowait condition · 8c34ab19
    Rafael J. Wysocki authored
    Testing indicates that it is possible to improve performace
    significantly without increasing energy consumption too much by
    teaching cpufreq governors to bump up the CPU performance level if
    the in_iowait flag is set for the task in enqueue_task_fair().
    
    For this purpose, define a new cpufreq_update_util() flag
    SCHED_CPUFREQ_IOWAIT and modify enqueue_task_fair() to pass that
    flag to cpufreq_update_util() in the in_iowait case.  That generally
    requires cpufreq_update_util() to be called directly from there,
    because update_load_avg() may not be invoked in that case.
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    Looks-good-to: Steve Muckle <smuckle@linaro.org>
    Acked-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    8c34ab19
fair.c 231 KB