diff options
| author | Barry Song <song.bao.hua@hisilicon.com> | 2023-10-19 11:33:21 +0800 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-10-24 10:38:42 +0200 |
| commit | b95303e0aeaf446b65169dd4142cacdaeb7d4c8b (patch) | |
| tree | 448ae9f3ea16e3d4593686bc929c059a8b8bd9f0 /kernel/sched | |
| parent | 5ebde09d91707a4a9bec1e3d213e3c12ffde348f (diff) | |
sched: Add cpus_share_resources API
Add cpus_share_resources() API. This is the preparation for the
optimization of select_idle_cpu() on platforms with cluster scheduler
level.
On a machine with clusters cpus_share_resources() will test whether
two cpus are within the same cluster. On a non-cluster machine it
will behaves the same as cpus_share_cache(). So we use "resources"
here for cache resources.
Signed-off-by: Barry Song <song.bao.hua@hisilicon.com>
Signed-off-by: Yicong Yang <yangyicong@hisilicon.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Gautham R. Shenoy <gautham.shenoy@amd.com>
Reviewed-by: Tim Chen <tim.c.chen@linux.intel.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-and-reviewed-by: Chen Yu <yu.c.chen@intel.com>
Tested-by: K Prateek Nayak <kprateek.nayak@amd.com>
Link: https://lkml.kernel.org/r/20231019033323.54147-2-yangyicong@huawei.com
Diffstat (limited to 'kernel/sched')
| -rw-r--r-- | kernel/sched/core.c | 12 | ||||
| -rw-r--r-- | kernel/sched/sched.h | 1 | ||||
| -rw-r--r-- | kernel/sched/topology.c | 13 |
3 files changed, 26 insertions, 0 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index dc724f59e495..5e1fb8a63b2e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -3939,6 +3939,18 @@ bool cpus_share_cache(int this_cpu, int that_cpu) return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); } +/* + * Whether CPUs are share cache resources, which means LLC on non-cluster + * machines and LLC tag or L2 on machines with clusters. + */ +bool cpus_share_resources(int this_cpu, int that_cpu) +{ + if (this_cpu == that_cpu) + return true; + + return per_cpu(sd_share_id, this_cpu) == per_cpu(sd_share_id, that_cpu); +} + static inline bool ttwu_queue_cond(struct task_struct *p, int cpu) { /* diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 65cad0e5729e..998f03d02de0 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1853,6 +1853,7 @@ static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); DECLARE_PER_CPU(int, sd_llc_size); DECLARE_PER_CPU(int, sd_llc_id); +DECLARE_PER_CPU(int, sd_share_id); DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index a63729f87c21..dbb8c328e8ad 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -668,6 +668,7 @@ static void destroy_sched_domains(struct sched_domain *sd) DEFINE_PER_CPU(struct sched_domain __rcu *, sd_llc); DEFINE_PER_CPU(int, sd_llc_size); DEFINE_PER_CPU(int, sd_llc_id); +DEFINE_PER_CPU(int, sd_share_id); DEFINE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); DEFINE_PER_CPU(struct sched_domain __rcu *, sd_numa); DEFINE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); @@ -693,6 +694,17 @@ static void update_top_cache_domain(int cpu) per_cpu(sd_llc_id, cpu) = id; rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds); + sd = lowest_flag_domain(cpu, SD_CLUSTER); + if (sd) + id = cpumask_first(sched_domain_span(sd)); + + /* + * This assignment should be placed after the sd_llc_id as + * we want this id equals to cluster id on cluster machines + * but equals to LLC id on non-Cluster machines. + */ + per_cpu(sd_share_id, cpu) = id; + sd = lowest_flag_domain(cpu, SD_NUMA); rcu_assign_pointer(per_cpu(sd_numa, cpu), sd); @@ -1550,6 +1562,7 @@ static struct cpumask ***sched_domains_numa_masks; */ #define TOPOLOGY_SD_FLAGS \ (SD_SHARE_CPUCAPACITY | \ + SD_CLUSTER | \ SD_SHARE_PKG_RESOURCES | \ SD_NUMA | \ SD_ASYM_PACKING) |