1 files changed, 16 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/cputhreads.h b/arch/powerpc/include/asm/cputhreads.h
index fb11b0c459b8..a8e18447c62b 100644
--- a/arch/powerpc/include/asm/cputhreads.h
+++ b/arch/powerpc/include/asm/cputhreads.h
@@ -5,6 +5,15 @@
 
 /*
  * Mapping of threads to cores
+ *
+ * Note: This implementation is limited to a power of 2 number of
+ * threads per core and the same number for each core in the system
+ * (though it would work if some processors had less threads as long
+ * as the CPU numbers are still allocated, just not brought offline).
+ *
+ * However, the API allows for a different implementation in the future
+ * if needed, as long as you only use the functions and not the variables
+ * directly.
  */
 
 #ifdef CONFIG_SMP
@@ -67,5 +76,12 @@ static inline int cpu_first_thread_in_core(int cpu)
         return cpu & ~(threads_per_core - 1);
 }
 
+static inline int cpu_last_thread_in_core(int cpu)
+{
+        return cpu | (threads_per_core - 1);
+}
+
+
+
 #endif /* _ASM_POWERPC_CPUTHREADS_H */