[POWERPC] Cleanup SMT thread handling

[linux-2.6-omap-h63xx.git] / include / asm-powerpc / cputhreads.h

diff --git a/include/asm-powerpc/cputhreads.h b/include/asm-powerpc/cputhreads.h
new file mode 100644 (file)
index 0000000..8485c28
--- /dev/null
+++ b/include/asm-powerpc/cputhreads.h
@@ -0,0 +1,71 @@
+#ifndef _ASM_POWERPC_CPUTHREADS_H
+#define _ASM_POWERPC_CPUTHREADS_H
+
+#include <linux/cpumask.h>
+
+/*
+ * Mapping of threads to cores
+ */
+
+#ifdef CONFIG_SMP
+extern int threads_per_core;
+extern int threads_shift;
+extern cpumask_t threads_core_mask;
+#else
+#define threads_per_core       1
+#define threads_shift          0
+#define threads_core_mask      (CPU_MASK_CPU0)
+#endif
+
+/* cpu_thread_mask_to_cores - Return a cpumask of one per cores
+ *                            hit by the argument
+ *
+ * @threads:   a cpumask of threads
+ *
+ * This function returns a cpumask which will have one "cpu" (or thread)
+ * bit set for each core that has at least one thread set in the argument.
+ *
+ * This can typically be used for things like IPI for tlb invalidations
+ * since those need to be done only once per core/TLB
+ */
+static inline cpumask_t cpu_thread_mask_to_cores(cpumask_t threads)
+{
+       cpumask_t       tmp, res;
+       int             i;
+
+       res = CPU_MASK_NONE;
+       for (i = 0; i < NR_CPUS; i += threads_per_core) {
+               cpus_shift_right(tmp, threads_core_mask, i);
+               if (cpus_intersects(threads, tmp))
+                       cpu_set(i, res);
+       }
+       return res;
+}
+
+static inline int cpu_nr_cores(void)
+{
+       return NR_CPUS >> threads_shift;
+}
+
+static inline cpumask_t cpu_online_cores_map(void)
+{
+       return cpu_thread_mask_to_cores(cpu_online_map);
+}
+
+static inline int cpu_thread_to_core(int cpu)
+{
+       return cpu >> threads_shift;
+}
+
+static inline int cpu_thread_in_core(int cpu)
+{
+       return cpu & (threads_per_core - 1);
+}
+
+static inline int cpu_first_thread_in_core(int cpu)
+{
+       return cpu & ~(threads_per_core - 1);
+}
+
+#endif /* _ASM_POWERPC_CPUTHREADS_H */
+