[PATCH] x86_64: Let impossible CPUs point to reference per cpu data

[powerpc.git] / arch / x86_64 / mm / numa.c

diff --git a/arch/x86_64/mm/numa.c b/arch/x86_64/mm/numa.c
index 42ec1f4..6ef9f9a 100644 (file)
--- a/arch/x86_64/mm/numa.c
+++ b/arch/x86_64/mm/numa.c
@@ -272,7 +272,7 @@ __cpuinit void numa_add_cpu(int cpu)
 
 void __cpuinit numa_set_node(int cpu, int node)
 {
-       cpu_pda[cpu].nodenumber = node;
+       cpu_pda(cpu)->nodenumber = node;
        cpu_to_node[cpu] = node;
 }
 
@@ -330,8 +330,69 @@ __init int numa_setup(char *opt)
        return 1;
 } 
 
+/*
+ * Setup early cpu_to_node.
+ *
+ * Populate cpu_to_node[] only if x86_cpu_to_apicid[],
+ * and apicid_to_node[] tables have valid entries for a CPU.
+ * This means we skip cpu_to_node[] initialisation for NUMA
+ * emulation and faking node case (when running a kernel compiled
+ * for NUMA on a non NUMA box), which is OK as cpu_to_node[]
+ * is already initialized in a round robin manner at numa_init_array,
+ * prior to this call, and this initialization is good enough
+ * for the fake NUMA cases.
+ */
+void __init init_cpu_to_node(void)
+{
+       int i;
+       for (i = 0; i < NR_CPUS; i++) {
+               u8 apicid = x86_cpu_to_apicid[i];
+               if (apicid == BAD_APICID)
+                       continue;
+               if (apicid_to_node[apicid] == NUMA_NO_NODE)
+                       continue;
+               cpu_to_node[i] = apicid_to_node[apicid];
+       }
+}
+
 EXPORT_SYMBOL(cpu_to_node);
 EXPORT_SYMBOL(node_to_cpumask);
 EXPORT_SYMBOL(memnode_shift);
 EXPORT_SYMBOL(memnodemap);
 EXPORT_SYMBOL(node_data);
+
+#ifdef CONFIG_DISCONTIGMEM
+/*
+ * Functions to convert PFNs from/to per node page addresses.
+ * These are out of line because they are quite big.
+ * They could be all tuned by pre caching more state.
+ * Should do that.
+ */
+
+/* Requires pfn_valid(pfn) to be true */
+struct page *pfn_to_page(unsigned long pfn)
+{
+       int nid = phys_to_nid(((unsigned long)(pfn)) << PAGE_SHIFT);
+       return (pfn - node_start_pfn(nid)) + NODE_DATA(nid)->node_mem_map;
+}
+EXPORT_SYMBOL(pfn_to_page);
+
+unsigned long page_to_pfn(struct page *page)
+{
+       return (long)(((page) - page_zone(page)->zone_mem_map) +
+                     page_zone(page)->zone_start_pfn);
+}
+EXPORT_SYMBOL(page_to_pfn);
+
+int pfn_valid(unsigned long pfn)
+{
+       unsigned nid;
+       if (pfn >= num_physpages)
+               return 0;
+       nid = pfn_to_nid(pfn);
+       if (nid == 0xff)
+               return 0;
+       return pfn >= node_start_pfn(nid) && (pfn) < node_end_pfn(nid);
+}
+EXPORT_SYMBOL(pfn_valid);
+#endif