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Kernel tracks such nodes with N_CPU record in node_states array. Switching to it makes for_each_node_with_cpus() O(N). Signed-off-by: Yury Norov [NVIDIA] --- include/linux/nodemask.h | 1 + include/linux/topology.h | 5 +---- 2 files changed, 2 insertions(+), 4 deletions(-) diff --git a/include/linux/nodemask.h b/include/linux/nodemask.h index f0ac0633366b..1e2bdda1a0a5 100644 --- a/include/linux/nodemask.h +++ b/include/linux/nodemask.h @@ -541,6 +541,7 @@ static __always_inline int node_random(const nodemask_t= *maskp) =20 #define for_each_node(node) for_each_node_state(node, N_POSSIBLE) #define for_each_online_node(node) for_each_node_state(node, N_ONLINE) +#define for_each_node_with_cpus(node) for_each_node_state(node, N_CPU) =20 /* * For nodemask scratch area. diff --git a/include/linux/topology.h b/include/linux/topology.h index 24e715f0f6d2..ffee6b4a071a 100644 --- a/include/linux/topology.h +++ b/include/linux/topology.h @@ -29,6 +29,7 @@ =20 #include #include +#include #include #include #include @@ -39,10 +40,6 @@ #define nr_cpus_node(node) cpumask_weight(cpumask_of_node(node)) #endif =20 -#define for_each_node_with_cpus(node) \ - for_each_online_node(node) \ - if (nr_cpus_node(node)) - int arch_update_cpu_topology(void); =20 /* Conform to ACPI 2.0 SLIT distance definitions */ --=20 2.43.0