Overutilized field is accessed directly in multiple places.
So it could use a helper function. That way one might be more
informed that it needs to be used only in case of EAS.
No change in functionality intended.
Reviewed-by: Qais Yousef <[email protected]>
Signed-off-by: Shrikanth Hegde <[email protected]>
---
kernel/sched/fair.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 5aa6e918598c..87e08a252f94 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6675,6 +6675,15 @@ static inline bool cpu_overutilized(int cpu)
return !util_fits_cpu(cpu_util_cfs(cpu), rq_util_min, rq_util_max, cpu);
}
+/*
+ * Ensure that caller can do EAS. overutilized value
+ * make sense only if EAS is enabled
+ */
+static inline int is_rd_overutilized(struct root_domain *rd)
+{
+ return READ_ONCE(rd->overutilized);
+}
+
static inline void set_rd_overutilized_status(struct root_domain *rd,
unsigned int status)
{
@@ -6694,7 +6703,7 @@ static inline void check_update_overutilized_status(struct rq *rq)
if (!sched_energy_enabled())
return;
- if (!READ_ONCE(rq->rd->overutilized) && cpu_overutilized(rq->cpu))
+ if (!is_rd_overutilized(rq->rd) && cpu_overutilized(rq->cpu))
set_rd_overutilized_status(rq->rd, SG_OVERUTILIZED);
}
#else
@@ -7980,7 +7989,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
rcu_read_lock();
pd = rcu_dereference(rd->pd);
- if (!pd || READ_ONCE(rd->overutilized))
+ if (!pd || is_rd_overutilized(rd))
goto unlock;
/*
@@ -10863,7 +10872,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
if (sched_energy_enabled()) {
struct root_domain *rd = env->dst_rq->rd;
- if (rcu_dereference(rd->pd) && !READ_ONCE(rd->overutilized))
+ if (rcu_dereference(rd->pd) && !is_rd_overutilized(rd))
goto out_balanced;
}
--
2.39.3
On Thu, 7 Mar 2024 at 09:58, Shrikanth Hegde <[email protected]> wrote:
>
> Overutilized field is accessed directly in multiple places.
> So it could use a helper function. That way one might be more
> informed that it needs to be used only in case of EAS.
>
> No change in functionality intended.
>
> Reviewed-by: Qais Yousef <[email protected]>
> Signed-off-by: Shrikanth Hegde <[email protected]>
Reviewed-by: Vincent Guittot <[email protected]>
> ---
> kernel/sched/fair.c | 15 ++++++++++++---
> 1 file changed, 12 insertions(+), 3 deletions(-)
>
> diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
> index 5aa6e918598c..87e08a252f94 100644
> --- a/kernel/sched/fair.c
> +++ b/kernel/sched/fair.c
> @@ -6675,6 +6675,15 @@ static inline bool cpu_overutilized(int cpu)
> return !util_fits_cpu(cpu_util_cfs(cpu), rq_util_min, rq_util_max, cpu);
> }
>
> +/*
> + * Ensure that caller can do EAS. overutilized value
> + * make sense only if EAS is enabled
> + */
> +static inline int is_rd_overutilized(struct root_domain *rd)
> +{
> + return READ_ONCE(rd->overutilized);
> +}
> +
> static inline void set_rd_overutilized_status(struct root_domain *rd,
> unsigned int status)
> {
> @@ -6694,7 +6703,7 @@ static inline void check_update_overutilized_status(struct rq *rq)
> if (!sched_energy_enabled())
> return;
>
> - if (!READ_ONCE(rq->rd->overutilized) && cpu_overutilized(rq->cpu))
> + if (!is_rd_overutilized(rq->rd) && cpu_overutilized(rq->cpu))
> set_rd_overutilized_status(rq->rd, SG_OVERUTILIZED);
> }
> #else
> @@ -7980,7 +7989,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
>
> rcu_read_lock();
> pd = rcu_dereference(rd->pd);
> - if (!pd || READ_ONCE(rd->overutilized))
> + if (!pd || is_rd_overutilized(rd))
> goto unlock;
>
> /*
> @@ -10863,7 +10872,7 @@ static struct sched_group *find_busiest_group(struct lb_env *env)
> if (sched_energy_enabled()) {
> struct root_domain *rd = env->dst_rq->rd;
>
> - if (rcu_dereference(rd->pd) && !READ_ONCE(rd->overutilized))
> + if (rcu_dereference(rd->pd) && !is_rd_overutilized(rd))
> goto out_balanced;
> }
>
> --
> 2.39.3
>
The following commit has been merged into the sched/core branch of tip:
Commit-ID: d0f5d3cefc259f498456338d319098dc84393b24
Gitweb: https://git.kernel.org/tip/d0f5d3cefc259f498456338d319098dc84393b24
Author: Shrikanth Hegde <[email protected]>
AuthorDate: Thu, 07 Mar 2024 14:27:24 +05:30
Committer: Ingo Molnar <[email protected]>
CommitterDate: Tue, 26 Mar 2024 08:58:59 +01:00
sched/fair: Introduce is_rd_overutilized() helper function to access root_domain::overutilized
The root_domain::overutilized field is READ_ONCE() accessed in
multiple places, which could be simplified with a helper function.
This might also make it more apparent that it needs to be used
only in case of EAS.
No change in functionality intended.
Signed-off-by: Shrikanth Hegde <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Reviewed-by: Qais Yousef <[email protected]>
Reviewed-by: Vincent Guittot <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
---
kernel/sched/fair.c | 15 ++++++++++++---
1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 1afa4f8..24a7530 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -6685,6 +6685,15 @@ static inline bool cpu_overutilized(int cpu)
return !util_fits_cpu(cpu_util_cfs(cpu), rq_util_min, rq_util_max, cpu);
}
+/*
+ * Ensure that caller can do EAS. overutilized value
+ * make sense only if EAS is enabled
+ */
+static inline int is_rd_overutilized(struct root_domain *rd)
+{
+ return READ_ONCE(rd->overutilized);
+}
+
static inline void set_rd_overutilized_status(struct root_domain *rd,
unsigned int status)
{
@@ -6704,7 +6713,7 @@ static inline void check_update_overutilized_status(struct rq *rq)
if (!sched_energy_enabled())
return;
- if (!READ_ONCE(rq->rd->overutilized) && cpu_overutilized(rq->cpu))
+ if (!is_rd_overutilized(rq->rd) && cpu_overutilized(rq->cpu))
set_rd_overutilized_status(rq->rd, SG_OVERUTILIZED);
}
#else
@@ -7990,7 +7999,7 @@ static int find_energy_efficient_cpu(struct task_struct *p, int prev_cpu)
rcu_read_lock();
pd = rcu_dereference(rd->pd);
- if (!pd || READ_ONCE(rd->overutilized))
+ if (!pd || is_rd_overutilized(rd))
goto unlock;
/*
@@ -10897,7 +10906,7 @@ static struct sched_group *sched_balance_find_src_group(struct lb_env *env)
if (sched_energy_enabled()) {
struct root_domain *rd = env->dst_rq->rd;
- if (rcu_dereference(rd->pd) && !READ_ONCE(rd->overutilized))
+ if (rcu_dereference(rd->pd) && !is_rd_overutilized(rd))
goto out_balanced;
}