diff options
Diffstat (limited to 'meta-eas/recipes-kernel/linux/linux-renesas/0004-sched-fair-Add-per-CPU-min-capacity-to-sched_group_c.patch')
| -rw-r--r-- | meta-eas/recipes-kernel/linux/linux-renesas/0004-sched-fair-Add-per-CPU-min-capacity-to-sched_group_c.patch | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/meta-eas/recipes-kernel/linux/linux-renesas/0004-sched-fair-Add-per-CPU-min-capacity-to-sched_group_c.patch b/meta-eas/recipes-kernel/linux/linux-renesas/0004-sched-fair-Add-per-CPU-min-capacity-to-sched_group_c.patch new file mode 100644 index 0000000..7932e0b --- /dev/null +++ b/meta-eas/recipes-kernel/linux/linux-renesas/0004-sched-fair-Add-per-CPU-min-capacity-to-sched_group_c.patch @@ -0,0 +1,143 @@ +From 9a434b62bbd9621f05318569949b59d37a0f59ce Mon Sep 17 00:00:00 2001 +From: Morten Rasmussen <morten.rasmussen@arm.com> +Date: Fri, 14 Oct 2016 14:41:09 +0100 +Subject: [PATCH 04/92] sched/fair: Add per-CPU min capacity to + sched_group_capacity + +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: Morten Rasmussen <morten.rasmussen@arm.com> +Signed-off-by: Peter 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.com +Signed-off-by: Ingo Molnar <mingo@kernel.org> +(cherry picked from commit bf475ce0a3dd75b5d1df6c6c14ae25168caa15ac) +Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com> +--- + kernel/sched/core.c | 3 ++- + kernel/sched/fair.c | 17 ++++++++++++----- + kernel/sched/sched.h | 3 ++- + 3 files changed, 16 insertions(+), 7 deletions(-) + +diff --git a/kernel/sched/core.c b/kernel/sched/core.c +index 154fd68..e891e12 100644 +--- a/kernel/sched/core.c ++++ b/kernel/sched/core.c +@@ -5707,7 +5707,7 @@ static int sched_domain_debug_one(struct sched_domain *sd, int cpu, int level, + printk(KERN_CONT " %*pbl", + cpumask_pr_args(sched_group_cpus(group))); + if (group->sgc->capacity != SCHED_CAPACITY_SCALE) { +- printk(KERN_CONT " (cpu_capacity = %d)", ++ printk(KERN_CONT " (cpu_capacity = %lu)", + group->sgc->capacity); + } + +@@ -6184,6 +6184,7 @@ int group_balance_cpu(struct sched_group *sg) + * die on a /0 trap. + */ + sg->sgc->capacity = SCHED_CAPACITY_SCALE * cpumask_weight(sg_span); ++ sg->sgc->min_capacity = SCHED_CAPACITY_SCALE; + + /* + * Make sure the first group of this domain contains the +diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c +index 1ad3706..faf8f18 100644 +--- a/kernel/sched/fair.c ++++ b/kernel/sched/fair.c +@@ -6909,13 +6909,14 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) + + cpu_rq(cpu)->cpu_capacity = capacity; + sdg->sgc->capacity = capacity; ++ sdg->sgc->min_capacity = capacity; + } + + void update_group_capacity(struct sched_domain *sd, int cpu) + { + struct sched_domain *child = sd->child; + struct sched_group *group, *sdg = sd->groups; +- unsigned long capacity; ++ unsigned long capacity, min_capacity; + unsigned long interval; + + interval = msecs_to_jiffies(sd->balance_interval); +@@ -6928,6 +6929,7 @@ void update_group_capacity(struct sched_domain *sd, int cpu) + } + + capacity = 0; ++ min_capacity = ULONG_MAX; + + if (child->flags & SD_OVERLAP) { + /* +@@ -6952,11 +6954,12 @@ void update_group_capacity(struct sched_domain *sd, int cpu) + */ + if (unlikely(!rq->sd)) { + capacity += capacity_of(cpu); +- continue; ++ } else { ++ sgc = rq->sd->groups->sgc; ++ capacity += sgc->capacity; + } + +- sgc = rq->sd->groups->sgc; +- capacity += sgc->capacity; ++ min_capacity = min(capacity, min_capacity); + } + } else { + /* +@@ -6966,12 +6969,16 @@ void update_group_capacity(struct sched_domain *sd, int cpu) + + group = child->groups; + do { +- capacity += group->sgc->capacity; ++ struct sched_group_capacity *sgc = group->sgc; ++ ++ capacity += sgc->capacity; ++ min_capacity = min(sgc->min_capacity, min_capacity); + group = group->next; + } while (group != child->groups); + } + + sdg->sgc->capacity = capacity; ++ sdg->sgc->min_capacity = min_capacity; + } + + /* +diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h +index 055f935..345c1cc 100644 +--- a/kernel/sched/sched.h ++++ b/kernel/sched/sched.h +@@ -892,7 +892,8 @@ struct sched_group_capacity { + * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity + * for a single CPU. + */ +- unsigned int capacity; ++ unsigned long capacity; ++ unsigned long min_capacity; /* Min per-CPU capacity in group */ + unsigned long next_update; + int imbalance; /* XXX unrelated to capacity but shared group state */ + +-- +1.9.1 + |