[PATCH 3/3] arm64: add arm64 default topology

[Qing Wang]

From: Wang Qing <wangq...@vivo.com>

default_topology does not fit arm64, especially CPU and cache topology.
Add arm64_topology, so we can do more based on CONFIG_GENERIC_ARCH_TOPOLOGY.

arm64_xxx_flags() prefer to get the cache attribute from DT.

Signed-off-by: Wang Qing <wangq...@vivo.com>
---
 arch/arm64/kernel/smp.c | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)

diff --git a/arch/arm64/kernel/smp.c b/arch/arm64/kernel/smp.c
index 27df5c1..d245012
--- a/arch/arm64/kernel/smp.c
+++ b/arch/arm64/kernel/smp.c
@@ -715,6 +715,60 @@ void __init smp_init_cpus(void)
        }
 }
 
+#ifdef CONFIG_SCHED_CLUSTER
+static int arm64_cluster_flags(const struct cpumask *cpu_map)
+{
+       int flag = cpu_cluster_flags();
+       int ret = cpu_share_private_cache(cpu_map);
+       if (ret == 1)
+               flag |= SD_SHARE_PKG_RESOURCES;
+       else if (ret == 0)
+               flag &= ~SD_SHARE_PKG_RESOURCES;
+
+       return flag;
+}
+#endif
+
+#ifdef CONFIG_SCHED_MC
+static int arm64_core_flags(const struct cpumask *cpu_map)
+{
+       int flag = cpu_core_flags();
+       int ret = cpu_share_private_cache(cpu_map);
+       if (ret == 1)
+               flag |= SD_SHARE_PKG_RESOURCES;
+       else if (ret == 0)
+               flag &= ~SD_SHARE_PKG_RESOURCES;
+
+       return flag;
+}
+#endif
+
+static int arm64_die_flags(const struct cpumask *cpu_map)
+{
+       int flag = 0;
+       int ret = cpu_share_private_cache(cpu_map);
+       if (ret == 1)
+               flag |= SD_SHARE_PKG_RESOURCES;
+       else if (ret == 0)
+               flag &= ~SD_SHARE_PKG_RESOURCES;
+
+       return flag;
+}
+
+static struct sched_domain_topology_level arm64_topology[] = {
+#ifdef CONFIG_SCHED_SMT
+       { cpu_smt_mask, cpu_smt_flags, SD_INIT_NAME(SMT) },
+#endif
+#ifdef CONFIG_SCHED_CLUSTER
+       { cpu_clustergroup_mask, arm64_cluster_flags, SD_INIT_NAME(CLS) },
+#endif
+#ifdef CONFIG_SCHED_MC
+       { cpu_coregroup_mask, arm64_core_flags, SD_INIT_NAME(MC) },
+#endif
+       { cpu_cpu_mask, arm64_die_flags, SD_INIT_NAME(DIE) },
+       { NULL, },
+};
+
 void __init smp_prepare_cpus(unsigned int max_cpus)
 {
        const struct cpu_operations *ops;
@@ -723,6 +777,8 @@ void __init smp_prepare_cpus(unsigned int max_cpus)
        unsigned int this_cpu;
 
        init_cpu_topology();
+       init_cpu_cache_topology();
+       set_sched_topology(arm64_topology);
 
        this_cpu = smp_processor_id();
        store_cpu_topology(this_cpu);
-- 
2.7.4