i386 Topology Fix

diff -Nur --exclude-from=/usr/src/.dontdiff linux-2.5.46-vanilla/arch/i386/kernel/smpboot.c linux-2.5.46-i386_topo_fix/arch/i386/kernel/smpboot.c
@@ -501,6 +501,46 @@
 	return do_fork(CLONE_VM|CLONE_IDLETASK, 0, &regs, 0, NULL);
 }
 
+#ifdef CONFIG_X86_NUMAQ
+/* which logical CPUs are on which nodes */
+volatile unsigned long node_2_cpu_mask[MAX_NR_NODES];
+/* which node each logical CPU is on */
+volatile int cpu_2_node[NR_CPUS];
+
+/* Initialize all maps between cpu number and node */
+static inline void init_cpu_to_node_mapping(void)
+{
+	int node, cpu;
+
+	for (node = 0; node < MAX_NR_NODES; node++) {
+		node_2_cpu_mask[node] = 0;
+	}
+	for (cpu = 0; cpu < NR_CPUS; cpu++) {
+		cpu_2_node[cpu] = -1;
+	}
+}
+
+/* set up a mapping between cpu and node. */
+static inline void map_cpu_to_node(int cpu, int node)
+{
+	node_2_cpu_mask[node] |= (1 << cpu);
+	cpu_2_node[cpu] = node;
+}
+
+/* undo a mapping between cpu and node. */
+static inline void unmap_cpu_to_node(int cpu, int node)
+{
+	node_2_cpu_mask[node] &= ~(1 << cpu);
+	cpu_2_node[cpu] = -1;
+}
+#else /* !CONFIG_X86_NUMAQ */
+
+#define init_cpu_to_node_mapping()	({})
+#define map_cpu_to_node(cpu, node)	({})
+#define unmap_cpu_to_node(cpu, node)	({})
+
+#endif /* CONFIG_X86_NUMAQ */
+
 /* which physical APIC ID maps to which logical CPU number */
 volatile int physical_apicid_2_cpu[MAX_APICID];
 /* which logical CPU number maps to which physical APIC ID */

@@ -524,6 +564,7 @@
 		cpu_2_physical_apicid[cpu] = -1;
 		cpu_2_logical_apicid[cpu] = -1;
 	}
+	init_cpu_to_node_mapping();
 }
 
 static inline void map_cpu_to_boot_apicid(int cpu, int apicid)

@@ -535,6 +576,7 @@
 	if (clustered_apic_mode) {
 		logical_apicid_2_cpu[apicid] = cpu;	
 		cpu_2_logical_apicid[cpu] = apicid;
+		map_cpu_to_node(cpu, apicid >> 4);
 	} else {
 		physical_apicid_2_cpu[apicid] = cpu;	
 		cpu_2_physical_apicid[cpu] = apicid;

@@ -550,6 +592,7 @@
 	if (clustered_apic_mode) {
 		logical_apicid_2_cpu[apicid] = -1;	
 		cpu_2_logical_apicid[cpu] = -1;
+		unmap_cpu_to_node(cpu, apicid >> 4);
 	} else {
 		physical_apicid_2_cpu[apicid] = -1;	
 		cpu_2_physical_apicid[cpu] = -1;

diff -Nur --exclude-from=/usr/src/.dontdiff linux-2.5.46-vanilla/include/asm-i386/smpboot.h linux-2.5.46-i386_topo_fix/include/asm-i386/smpboot.h
@@ -23,6 +23,14 @@
  #define boot_cpu_apicid boot_cpu_physical_apicid
 #endif /* CONFIG_CLUSTERED_APIC */
 
+#ifdef CONFIG_X86_NUMAQ
+/*
+ * Mappings between logical cpu number and node number
+ */
+extern volatile unsigned long node_2_cpu_mask[];
+extern volatile int cpu_2_node[];
+#endif /* CONFIG_X86_NUMAQ */
+
 /*
  * Mappings between logical cpu number and logical / physical apicid
  * The first four macros are trivial, but it keeps the abstraction consistent

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