[PATCH v2 03/10] sched/topology: Provide cfs_overload_cpus bitmap
From: Steve Sistare Define and initialize a sparse bitmap of overloaded CPUs, per last-level-cache scheduling domain, for use by the CFS scheduling class. Save a pointer to cfs_overload_cpus in the rq for efficient access. Signed-off-by: Steve Sistare --- include/linux/sched/topology.h | 1 + kernel/sched/sched.h | 2 ++ kernel/sched/topology.c| 21 +++-- 3 files changed, 22 insertions(+), 2 deletions(-) diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 2634774..8bac15d 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -72,6 +72,7 @@ struct sched_domain_shared { atomic_tref; atomic_tnr_busy_cpus; int has_idle_cores; + struct sparsemask *cfs_overload_cpus; }; struct sched_domain { diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 455fa33..aadfe68 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -81,6 +81,7 @@ struct rq; struct cpuidle_state; +struct sparsemask; /* task_struct::on_rq states: */ #define TASK_ON_RQ_QUEUED 1 @@ -805,6 +806,7 @@ struct rq { struct cfs_rq cfs; struct rt_rqrt; struct dl_rqdl; + struct sparsemask *cfs_overload_cpus; #ifdef CONFIG_FAIR_GROUP_SCHED /* list of leaf cfs_rq on this CPU: */ diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index a2363f6..f18c416 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -3,6 +3,7 @@ * Scheduler topology setup/handling methods */ #include "sched.h" +#include DEFINE_MUTEX(sched_domains_mutex); @@ -440,6 +441,7 @@ static void update_top_cache_domain(int cpu) static void cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) { + struct sparsemask *cfs_overload_cpus; struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; @@ -481,6 +483,10 @@ static void update_top_cache_domain(int cpu) dirty_sched_domain_sysctl(cpu); destroy_sched_domains(tmp); + sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); + cfs_overload_cpus = (sd ? sd->shared->cfs_overload_cpus : NULL); + rcu_assign_pointer(rq->cfs_overload_cpus, cfs_overload_cpus); + update_top_cache_domain(cpu); } @@ -1611,9 +1617,19 @@ static void __sdt_free(const struct cpumask *cpu_map) } } +#define ZALLOC_MASK(maskp, nelems, node) \ + (!*(maskp) && !zalloc_sparsemask_node(maskp, nelems, \ + SPARSEMASK_DENSITY_DEFAULT, \ + GFP_KERNEL, node)) \ + static int sd_llc_alloc(struct sched_domain *sd) { - /* Allocate sd->shared data here. Empty for now. */ + struct sched_domain_shared *sds = sd->shared; + struct cpumask *span = sched_domain_span(sd); + int nid = cpu_to_node(cpumask_first(span)); + + if (ZALLOC_MASK(>cfs_overload_cpus, nr_cpu_ids, nid)) + return 1; return 0; } @@ -1625,7 +1641,8 @@ static void sd_llc_free(struct sched_domain *sd) if (!sds) return; - /* Free data here. Empty for now. */ + free_sparsemask(sds->cfs_overload_cpus); + sds->cfs_overload_cpus = NULL; } static int sd_llc_alloc_all(const struct cpumask *cpu_map, struct s_data *d) -- 1.8.3.1
[PATCH v2 03/10] sched/topology: Provide cfs_overload_cpus bitmap
From: Steve Sistare Define and initialize a sparse bitmap of overloaded CPUs, per last-level-cache scheduling domain, for use by the CFS scheduling class. Save a pointer to cfs_overload_cpus in the rq for efficient access. Signed-off-by: Steve Sistare --- include/linux/sched/topology.h | 1 + kernel/sched/sched.h | 2 ++ kernel/sched/topology.c| 21 +++-- 3 files changed, 22 insertions(+), 2 deletions(-) diff --git a/include/linux/sched/topology.h b/include/linux/sched/topology.h index 2634774..8bac15d 100644 --- a/include/linux/sched/topology.h +++ b/include/linux/sched/topology.h @@ -72,6 +72,7 @@ struct sched_domain_shared { atomic_tref; atomic_tnr_busy_cpus; int has_idle_cores; + struct sparsemask *cfs_overload_cpus; }; struct sched_domain { diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 455fa33..aadfe68 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -81,6 +81,7 @@ struct rq; struct cpuidle_state; +struct sparsemask; /* task_struct::on_rq states: */ #define TASK_ON_RQ_QUEUED 1 @@ -805,6 +806,7 @@ struct rq { struct cfs_rq cfs; struct rt_rqrt; struct dl_rqdl; + struct sparsemask *cfs_overload_cpus; #ifdef CONFIG_FAIR_GROUP_SCHED /* list of leaf cfs_rq on this CPU: */ diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index a2363f6..f18c416 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -3,6 +3,7 @@ * Scheduler topology setup/handling methods */ #include "sched.h" +#include DEFINE_MUTEX(sched_domains_mutex); @@ -440,6 +441,7 @@ static void update_top_cache_domain(int cpu) static void cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu) { + struct sparsemask *cfs_overload_cpus; struct rq *rq = cpu_rq(cpu); struct sched_domain *tmp; @@ -481,6 +483,10 @@ static void update_top_cache_domain(int cpu) dirty_sched_domain_sysctl(cpu); destroy_sched_domains(tmp); + sd = highest_flag_domain(cpu, SD_SHARE_PKG_RESOURCES); + cfs_overload_cpus = (sd ? sd->shared->cfs_overload_cpus : NULL); + rcu_assign_pointer(rq->cfs_overload_cpus, cfs_overload_cpus); + update_top_cache_domain(cpu); } @@ -1611,9 +1617,19 @@ static void __sdt_free(const struct cpumask *cpu_map) } } +#define ZALLOC_MASK(maskp, nelems, node) \ + (!*(maskp) && !zalloc_sparsemask_node(maskp, nelems, \ + SPARSEMASK_DENSITY_DEFAULT, \ + GFP_KERNEL, node)) \ + static int sd_llc_alloc(struct sched_domain *sd) { - /* Allocate sd->shared data here. Empty for now. */ + struct sched_domain_shared *sds = sd->shared; + struct cpumask *span = sched_domain_span(sd); + int nid = cpu_to_node(cpumask_first(span)); + + if (ZALLOC_MASK(>cfs_overload_cpus, nr_cpu_ids, nid)) + return 1; return 0; } @@ -1625,7 +1641,8 @@ static void sd_llc_free(struct sched_domain *sd) if (!sds) return; - /* Free data here. Empty for now. */ + free_sparsemask(sds->cfs_overload_cpus); + sds->cfs_overload_cpus = NULL; } static int sd_llc_alloc_all(const struct cpumask *cpu_map, struct s_data *d) -- 1.8.3.1