diff options
author | Morten Rasmussen <morten.rasmussen@arm.com> | 2016-02-25 12:47:54 +0000 |
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committer | Leo Yan <leo.yan@linaro.org> | 2016-05-10 16:49:54 +0800 |
commit | f2a8923298fe9a39cf4c9ad48bbcb0781483d1f9 (patch) | |
tree | 88a57d5aa0b959bb4d1737304fbaf766a5646cb6 /drivers/gpio | |
parent | 563ddb604e01393625aa56601188b7eeb20888da (diff) |
sched: Add group_misfit_task load-balance type
To maximize throughput in systems with reduced capacity cpus (e.g.
high RT/IRQ load and/or ARM big.LITTLE) load-balancing has to consider
task and cpu utilization as well as per-cpu compute capacity when
load-balancing in addition to the current average load based
load-balancing policy. Tasks that are scheduled on a reduced capacity
cpu need to be identified and migrated to a higher capacity cpu if
possible.
To implement this additional policy an additional group_type
(load-balance scenario) is added: group_misfit_task. This represents
scenarios where a sched_group has tasks that are not suitable for its
per-cpu capacity. group_misfit_task is only considered if the system is
not overloaded in any other way (group_imbalanced or group_overloaded).
Identifying misfit tasks requires the rq lock to be held. To avoid
taking remote rq locks to examine source sched_groups for misfit tasks,
each cpu is responsible for tracking misfit tasks themselves and update
the rq->misfit_task flag. This means checking task utilization when
tasks are scheduled and on sched_tick.
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Diffstat (limited to 'drivers/gpio')
0 files changed, 0 insertions, 0 deletions