arm64: topology: add support to remove cpu topology sibling masks

This patch adds support to remove all the CPU topology information using
clear_cpu_topology and also resetting the sibling information on other
sibling CPUs. This will be used in cpu_disable so that all the topology
sibling information is removed on CPU hotplug out.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Tested-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h
index df48212f767b2a17dcebd6970979e89392d3c21a..4c073d28f9e48deb4dd286d1d1eecd5dd4bb16fd 100644 (file)
--- a/arch/arm64/include/asm/topology.h
+++ b/arch/arm64/include/asm/topology.h
@@ -20,9 +20,11 @@ extern struct cpu_topology cpu_topology[NR_CPUS];
 #define topology_core_id(cpu)          (cpu_topology[cpu].core_id)
 #define topology_core_cpumask(cpu)     (&cpu_topology[cpu].core_sibling)
 #define topology_sibling_cpumask(cpu)  (&cpu_topology[cpu].thread_sibling)
+#define topology_llc_cpumask(cpu)      (&cpu_topology[cpu].llc_siblings)
 
 void init_cpu_topology(void);
 void store_cpu_topology(unsigned int cpuid);
+void remove_cpu_topology(unsigned int cpuid);
 const struct cpumask *cpu_coregroup_mask(int cpu);
 
 #ifdef CONFIG_NUMA

diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c
index b64733c5ea2883fad12e1fb6f0ed7c86de9fcbbc..cb81df5453593a6701263adf233c724c6edc4743 100644 (file)
--- a/arch/arm64/kernel/topology.c
+++ b/arch/arm64/kernel/topology.c
@@ -322,6 +322,20 @@ static void __init reset_cpu_topology(void)
        }
 }
 
+void remove_cpu_topology(unsigned int cpu)
+{
+       int sibling;
+
+       for_each_cpu(sibling, topology_core_cpumask(cpu))
+               cpumask_clear_cpu(cpu, topology_core_cpumask(sibling));
+       for_each_cpu(sibling, topology_sibling_cpumask(cpu))
+               cpumask_clear_cpu(cpu, topology_sibling_cpumask(sibling));
+       for_each_cpu(sibling, topology_llc_cpumask(cpu))
+               cpumask_clear_cpu(cpu, topology_llc_cpumask(sibling));
+
+       clear_cpu_topology(cpu);
+}
+
 #ifdef CONFIG_ACPI
 /*
  * Propagate the topology information of the processor_topology_node tree to the