So far uclamp_util() allows to clamp a specified utilization considering
the clamp values requested by RUNNABLE tasks in a CPU. For the Energy
Aware Scheduler (EAS) it is interesting to test how clamp values will
change when a task is becoming RUNNABLE on a given CPU.
For example, EAS is interested in comparing the energy impact of
different scheduling decisions and the clamp values can play a role on
that.
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 <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
---
kernel/sched/core.c | 13 +++++++++++++
kernel/sched/sched.h | 21 ++++++++++++++++++++-
2 files changed, 33 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index ab75e874fdcc..2226ddd1de04 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -869,6 +869,19 @@ uclamp_eff_get(struct task_struct *p, unsigned int clamp_id)
return uc_req;
}
+unsigned int uclamp_eff_value(struct task_struct *p, unsigned int clamp_id)
+{
+ struct uclamp_se uc_eff;
+
+ /* Task currently refcounted: use back-annotated (effective) value */
+ if (p->uclamp[clamp_id].active)
+ return p->uclamp[clamp_id].value;
+
+ uc_eff = uclamp_eff_get(p, clamp_id);
+
+ return uc_eff.value;
+}
+
/*
* When a task is enqueued on a rq, the clamp bucket currently defined by the
* task's uclamp::bucket_id is refcounted on that rq. This also immediately
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index c33a57f14743..ce2da8b9ff8c 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2266,11 +2266,20 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
#endif /* CONFIG_CPU_FREQ */
#ifdef CONFIG_UCLAMP_TASK
-static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
+unsigned int uclamp_eff_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_eff_value(p, UCLAMP_MIN));
+ max_util = max(max_util, uclamp_eff_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
@@ -2281,7 +2290,17 @@ 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;
--
2.21.0
Commit-ID: 9d20ad7dfc9a5cc64e33d725902d3863d350a66a
Gitweb: https://git.kernel.org/tip/9d20ad7dfc9a5cc64e33d725902d3863d350a66a
Author: Patrick Bellasi <[email protected]>
AuthorDate: Fri, 21 Jun 2019 09:42:11 +0100
Committer: Ingo Molnar <[email protected]>
CommitDate: Mon, 24 Jun 2019 19:23:48 +0200
sched/uclamp: Add uclamp_util_with()
So far uclamp_util() allows to clamp a specified utilization considering
the clamp values requested by RUNNABLE tasks in a CPU. For the Energy
Aware Scheduler (EAS) it is interesting to test how clamp values will
change when a task is becoming RUNNABLE on a given CPU.
For example, EAS is interested in comparing the energy impact of
different scheduling decisions and the clamp values can play a role on
that.
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 <[email protected]>
Signed-off-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Alessio Balsini <[email protected]>
Cc: Dietmar Eggemann <[email protected]>
Cc: Joel Fernandes <[email protected]>
Cc: Juri Lelli <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Morten Rasmussen <[email protected]>
Cc: Paul Turner <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Quentin Perret <[email protected]>
Cc: Rafael J . Wysocki <[email protected]>
Cc: Steve Muckle <[email protected]>
Cc: Suren Baghdasaryan <[email protected]>
Cc: Tejun Heo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Todd Kjos <[email protected]>
Cc: Vincent Guittot <[email protected]>
Cc: Viresh Kumar <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
---
kernel/sched/core.c | 13 +++++++++++++
kernel/sched/sched.h | 21 ++++++++++++++++++++-
2 files changed, 33 insertions(+), 1 deletion(-)
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 6cd5133f0c2a..fa43ce3962e7 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -880,6 +880,19 @@ uclamp_eff_get(struct task_struct *p, unsigned int clamp_id)
return uc_req;
}
+unsigned int uclamp_eff_value(struct task_struct *p, unsigned int clamp_id)
+{
+ struct uclamp_se uc_eff;
+
+ /* Task currently refcounted: use back-annotated (effective) value */
+ if (p->uclamp[clamp_id].active)
+ return p->uclamp[clamp_id].value;
+
+ uc_eff = uclamp_eff_get(p, clamp_id);
+
+ return uc_eff.value;
+}
+
/*
* When a task is enqueued on a rq, the clamp bucket currently defined by the
* task's uclamp::bucket_id is refcounted on that rq. This also immediately
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 9b0c77a99346..1783f6b4c2e0 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2266,11 +2266,20 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
#endif /* CONFIG_CPU_FREQ */
#ifdef CONFIG_UCLAMP_TASK
-static inline unsigned int uclamp_util(struct rq *rq, unsigned int util)
+unsigned int uclamp_eff_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_eff_value(p, UCLAMP_MIN));
+ max_util = max(max_util, uclamp_eff_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
@@ -2281,7 +2290,17 @@ 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;