[PATCH v6 10/16] sched/core: Add uclamp_util_with()
From: Patrick Bellasi <hidden>
Date: 2019-01-15 10:16:07
Also in:
linux-pm, lkml
Subsystem:
scheduler, the rest · Maintainers:
Ingo Molnar, Peter Zijlstra, Juri Lelli, Vincent Guittot, Linus Torvalds
Currently uclamp_util() allows to clamp a specified utilization considering the clamp values requested by RUNNABLE tasks in a CPU. Sometimes however, it could be interesting to verify how clamp values will change when a task is going to be running on a given CPU. For example, the Energy Aware Scheduler (EAS) is interested in evaluating and comparing the energy impact of different scheduling decisions. Add uclamp_util_with() which allows to clamp a given utilization by considering the possible impact on CPU clamp values of a specified task. Signed-off-by: Patrick Bellasi <redacted> Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> --- kernel/sched/core.c | 4 ++-- kernel/sched/sched.h | 21 ++++++++++++++++++++- 2 files changed, 22 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 1ed01f381641..b41db1190d28 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c@@ -904,8 +904,8 @@ static inline unsigned int uclamp_effective_bucket_id(struct task_struct *p, return bucket_id; } -static unsigned int uclamp_effective_value(struct task_struct *p, - unsigned int clamp_id) +unsigned int uclamp_effective_value(struct task_struct *p, + unsigned int clamp_id) { unsigned int clamp_value, bucket_id;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 95d62a2a0b44..b7ce3023d023 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h@@ -2268,11 +2268,20 @@ static inline unsigned int uclamp_none(int clamp_id) } #ifdef CONFIG_UCLAMP_TASK -static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) +unsigned int uclamp_effective_value(struct task_struct *p, unsigned int clamp_id); + +static __always_inline +unsigned int uclamp_util_with(struct rq *rq, unsigned int util, + struct task_struct *p) { unsigned int min_util = READ_ONCE(rq->uclamp[UCLAMP_MIN].value); unsigned int max_util = READ_ONCE(rq->uclamp[UCLAMP_MAX].value); + if (p) { + min_util = max(min_util, uclamp_effective_value(p, UCLAMP_MIN)); + max_util = max(max_util, uclamp_effective_value(p, UCLAMP_MAX)); + } + /* * Since CPU's {min,max}_util clamps are MAX aggregated considering * RUNNABLE tasks with _different_ clamps, we can end up with an
@@ -2283,7 +2292,17 @@ static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) return clamp(util, min_util, max_util); } + +static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) +{ + return uclamp_util_with(rq, util, NULL); +} #else /* CONFIG_UCLAMP_TASK */ +static inline unsigned int uclamp_util_with(struct rq *rq, unsigned int util, + struct task_struct *p) +{ + return util; +} static inline unsigned int uclamp_util(struct rq *rq, unsigned int util) { return util;
--
2.19.2