• Morten Rasmussen's avatar
    sched/fair: Add per-CPU min capacity to sched_group_capacity · bf475ce0
    Morten Rasmussen authored
    struct sched_group_capacity currently represents the compute capacity
    sum of all CPUs in the sched_group.
    
    Unless it is divided by the group_weight to get the average capacity
    per CPU, it hides differences in CPU capacity for mixed capacity systems
    (e.g. high RT/IRQ utilization or ARM big.LITTLE).
    
    But even the average may not be sufficient if the group covers CPUs of
    different capacities.
    
    Instead, by extending struct sched_group_capacity to indicate min per-CPU
    capacity in the group a suitable group for a given task utilization can
    more easily be found such that CPUs with reduced capacity can be avoided
    for tasks with high utilization (not implemented by this patch).
    Signed-off-by: default avatarMorten Rasmussen <morten.rasmussen@arm.com>
    Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
    Cc: Linus Torvalds <torvalds@linux-foundation.org>
    Cc: Peter Zijlstra <peterz@infradead.org>
    Cc: Thomas Gleixner <tglx@linutronix.de>
    Cc: dietmar.eggemann@arm.com
    Cc: freedom.tan@mediatek.com
    Cc: keita.kobayashi.ym@renesas.com
    Cc: mgalbraith@suse.de
    Cc: sgurrappadi@nvidia.com
    Cc: vincent.guittot@linaro.org
    Cc: yuyang.du@intel.com
    Link: http://lkml.kernel.org/r/1476452472-24740-4-git-send-email-morten.rasmussen@arm.comSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
    bf475ce0
core.c 217 KB