1 files changed, 85 insertions, 0 deletions

diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 200282b92981..40e4c1fbf76b 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -172,6 +172,91 @@ static void *per_cpu_node_setup(void *cpu_data, int node)
         return cpu_data;
 }
 
+#ifdef CONFIG_SMP
+/**
+ * setup_per_cpu_areas - setup percpu areas
+ *
+ * Arch code has already allocated and initialized percpu areas.  All
+ * this function has to do is to teach the determined layout to the
+ * dynamic percpu allocator, which happens to be more complex than
+ * creating whole new ones using helpers.
+ */
+void __init setup_per_cpu_areas(void)
+{
+        struct pcpu_alloc_info *ai;
+        struct pcpu_group_info *uninitialized_var(gi);
+        unsigned int *cpu_map;
+        void *base;
+        unsigned long base_offset;
+        unsigned int cpu;
+        ssize_t static_size, reserved_size, dyn_size;
+        int node, prev_node, unit, nr_units, rc;
+
+        ai = pcpu_alloc_alloc_info(MAX_NUMNODES, nr_cpu_ids);
+        if (!ai)
+                panic("failed to allocate pcpu_alloc_info");
+        cpu_map = ai->groups[0].cpu_map;
+
+        /* determine base */
+        base = (void *)ULONG_MAX;
+        for_each_possible_cpu(cpu)
+                base = min(base,
+                           (void *)(__per_cpu_offset[cpu] + __per_cpu_start));
+        base_offset = (void *)__per_cpu_start - base;
+
+        /* build cpu_map, units are grouped by node */
+        unit = 0;
+        for_each_node(node)
+                for_each_possible_cpu(cpu)
+                        if (node == node_cpuid[cpu].nid)
+                                cpu_map[unit++] = cpu;
+        nr_units = unit;
+
+        /* set basic parameters */
+        static_size = __per_cpu_end - __per_cpu_start;
+        reserved_size = PERCPU_MODULE_RESERVE;
+        dyn_size = PERCPU_PAGE_SIZE - static_size - reserved_size;
+        if (dyn_size < 0)
+                panic("percpu area overflow static=%zd reserved=%zd\n",
+                      static_size, reserved_size);
+
+        ai->static_size         = static_size;
+        ai->reserved_size       = reserved_size;
+        ai->dyn_size            = dyn_size;
+        ai->unit_size           = PERCPU_PAGE_SIZE;
+        ai->atom_size           = PAGE_SIZE;
+        ai->alloc_size          = PERCPU_PAGE_SIZE;
+
+        /*
+         * CPUs are put into groups according to node.  Walk cpu_map
+         * and create new groups at node boundaries.
+         */
+        prev_node = -1;
+        ai->nr_groups = 0;
+        for (unit = 0; unit < nr_units; unit++) {
+                cpu = cpu_map[unit];
+                node = node_cpuid[cpu].nid;
+
+                if (node == prev_node) {
+                        gi->nr_units++;
+                        continue;
+                }
+                prev_node = node;
+
+                gi = &ai->groups[ai->nr_groups++];
+                gi->nr_units            = 1;
+                gi->base_offset         = __per_cpu_offset[cpu] + base_offset;
+                gi->cpu_map             = &cpu_map[unit];
+        }
+
+        rc = pcpu_setup_first_chunk(ai, base);
+        if (rc)
+                panic("failed to setup percpu area (err=%d)", rc);
+
+        pcpu_free_alloc_info(ai);
+}
+#endif
+
 /**
  * fill_pernode - initialize pernode data.
  * @node: the node id.