include/asm-powerpc/cputhreads.h

   1 #ifndef _ASM_POWERPC_CPUTHREADS_H
   2 #define _ASM_POWERPC_CPUTHREADS_H
   3
   4 #include <linux/cpumask.h>
   5
   6 /*
   7  * Mapping of threads to cores
   8  */
   9
  10 #ifdef CONFIG_SMP
  11 extern int threads_per_core;
  12 extern int threads_shift;
  13 extern cpumask_t threads_core_mask;
  14 #else
  15 #define threads_per_core        1
  16 #define threads_shift           0
  17 #define threads_core_mask       (CPU_MASK_CPU0)
  18 #endif
  19
  20 /* cpu_thread_mask_to_cores - Return a cpumask of one per cores
  21  *                            hit by the argument
  22  *
  23  * @threads:    a cpumask of threads
  24  *
  25  * This function returns a cpumask which will have one "cpu" (or thread)
  26  * bit set for each core that has at least one thread set in the argument.
  27  *
  28  * This can typically be used for things like IPI for tlb invalidations
  29  * since those need to be done only once per core/TLB
  30  */
  31 static inline cpumask_t cpu_thread_mask_to_cores(cpumask_t threads)
  32 {
  33         cpumask_t       tmp, res;
  34         int             i;
  35
  36         res = CPU_MASK_NONE;
  37         for (i = 0; i < NR_CPUS; i += threads_per_core) {
  38                 cpus_shift_left(tmp, threads_core_mask, i);
  39                 if (cpus_intersects(threads, tmp))
  40                         cpu_set(i, res);
  41         }
  42         return res;
  43 }
  44
  45 static inline int cpu_nr_cores(void)
  46 {
  47         return NR_CPUS >> threads_shift;
  48 }
  49
  50 static inline cpumask_t cpu_online_cores_map(void)
  51 {
  52         return cpu_thread_mask_to_cores(cpu_online_map);
  53 }
  54
  55 static inline int cpu_thread_to_core(int cpu)
  56 {
  57         return cpu >> threads_shift;
  58 }
  59
  60 static inline int cpu_thread_in_core(int cpu)
  61 {
  62         return cpu & (threads_per_core - 1);
  63 }
  64
  65 static inline int cpu_first_thread_in_core(int cpu)
  66 {
  67         return cpu & ~(threads_per_core - 1);
  68 }
  69
  70 #endif /* _ASM_POWERPC_CPUTHREADS_H */
  71