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-rw-r--r--arch/ia64/kernel/smpboot.c24
-rw-r--r--include/asm-ia64/smp.h1
2 files changed, 25 insertions, 0 deletions
diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c
index 6203ed4ec8c..f7d7f566814 100644
--- a/arch/ia64/kernel/smpboot.c
+++ b/arch/ia64/kernel/smpboot.c
@@ -879,3 +879,27 @@ identify_siblings(struct cpuinfo_ia64 *c)
c->core_id = info.log1_cid;
c->thread_id = info.log1_tid;
}
+
+/*
+ * returns non zero, if multi-threading is enabled
+ * on at least one physical package. Due to hotplug cpu
+ * and (maxcpus=), all threads may not necessarily be enabled
+ * even though the processor supports multi-threading.
+ */
+int is_multithreading_enabled(void)
+{
+ int i, j;
+
+ for_each_present_cpu(i) {
+ for_each_present_cpu(j) {
+ if (j == i)
+ continue;
+ if ((cpu_data(j)->socket_id == cpu_data(i)->socket_id)) {
+ if (cpu_data(j)->core_id == cpu_data(i)->core_id)
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+EXPORT_SYMBOL_GPL(is_multithreading_enabled);
diff --git a/include/asm-ia64/smp.h b/include/asm-ia64/smp.h
index 719ff309ce0..6533eb4e86a 100644
--- a/include/asm-ia64/smp.h
+++ b/include/asm-ia64/smp.h
@@ -128,6 +128,7 @@ extern void smp_send_reschedule (int cpu);
extern void lock_ipi_calllock(void);
extern void unlock_ipi_calllock(void);
extern void identify_siblings (struct cpuinfo_ia64 *);
+extern int is_multithreading_enabled(void);
#else