Task Affinity API

[tlwilmar]

Summary

This patch adds __kmpc_omp_reg_task_with_affinity to register affinity information for tasks. For now, the affinity information is not used, and the function always succeeds. This also adds the kmp_task_affinity_info_t structure to store the task affinity information.

[jklinkenberg]

Looks good to me :)

openmp/trunk/runtime/src/dllexports

 
 # OpenMP 5.0 entry points
 %ifndef stub
     %ifdef OMP_50
         __kmpc_task_reduction_init          268
         __kmpc_task_reduction_get_th_data   269
 # USED FOR 4.5 __kmpc_critical_with_hint    270
         __kmpc_get_target_offload           271
+  __kmpc_omp_reg_task_with_affinity   272
     %endif
 %endif
 
 # User API entry points that have both lower- and upper- case versions for Fortran.
 # Number for lowercase version is indicated.  Number for uppercase is obtained by adding 1000.
 # User API entry points are entry points that start with 'kmp_' or 'omp_'.
 
 omp_destroy_lock                            700

openmp/trunk/runtime/src/kmp.h

typedef struct kmp_dephash {
   kmp_dephash_entry_t **buckets;
   size_t size;
 #ifdef KMP_DEBUG
   kmp_uint32 nelements;
   kmp_uint32 nconflicts;
 #endif
 } kmp_dephash_t;
 
+#if OMP_50_ENABLED
+typedef struct kmp_task_affinity_info {
+  kmp_intptr_t base_addr;
+  size_t len;
+  struct {
+    bool flag1 : 1;
+    bool flag2 : 1;
+    kmp_int32 reserved : 30;
+  } flags;
+} kmp_task_affinity_info_t;
+#endif
+
 #endif
 
 #ifdef BUILD_TIED_TASK_STACK
 
 /* Tied Task stack definitions */
 typedef struct kmp_stack_block {
   kmp_taskdata_t *sb_block[TASK_STACK_BLOCK_SIZE];
   struct kmp_stack_block *sb_next;
KMP_EXPORT void __kmpc_taskloop(ident_t *loc, kmp_int32 gtid, kmp_task_t *task,
                                 kmp_int32 if_val, kmp_uint64 *lb,
                                 kmp_uint64 *ub, kmp_int64 st, kmp_int32 nogroup,
                                 kmp_int32 sched, kmp_uint64 grainsize,
                                 void *task_dup);
 #endif
 #if OMP_50_ENABLED
 KMP_EXPORT void *__kmpc_task_reduction_init(int gtid, int num_data, void *data);
 KMP_EXPORT void *__kmpc_task_reduction_get_th_data(int gtid, void *tg, void *d);
+KMP_EXPORT kmp_int32 __kmpc_omp_reg_task_with_affinity(
+    ident_t *loc_ref, kmp_int32 gtid, kmp_task_t *new_task, kmp_int32 naffins,
+    kmp_task_affinity_info_t *affin_list);
 #endif
 
 #endif
 
 /* Lock interface routines (fast versions with gtid passed in) */
 KMP_EXPORT void __kmpc_init_lock(ident_t *loc, kmp_int32 gtid,
                                  void **user_lock);
 KMP_EXPORT void __kmpc_init_nest_lock(ident_t *loc, kmp_int32 gtid,

openmp/trunk/runtime/src/kmp_tasking.cpp

#endif
   retval = __kmp_task_alloc(loc_ref, gtid, input_flags, sizeof_kmp_task_t,
                             sizeof_shareds, task_entry);
 
   KA_TRACE(20, ("__kmpc_omp_task_alloc(exit): T#%d retval %p\n", gtid, retval));
 
   return retval;
 }
 
+#if OMP_50_ENABLED
+/*!
+@ingroup TASKING
+@param loc_ref location of the original task directive
+@param gtid Global Thread ID of encountering thread
+@param new_task task thunk allocated by __kmpc_omp_task_alloc() for the ''new
+task''
+@param naffins Number of affinity items
+@param affin_list List of affinity items
+@return Returns non-zero if registering affinity information was not successful.
+ Returns 0 if registration was successful
+This entry registers the affinity information attached to a task with the task
+thunk structure kmp_taskdata_t.
+*/
+kmp_int32
+__kmpc_omp_reg_task_with_affinity(ident_t *loc_ref, kmp_int32 gtid,
+                                  kmp_task_t *new_task, kmp_int32 naffins,
+                                  kmp_task_affinity_info_t *affin_list) {
+  return 0;
+}
+#endif
+
 //  __kmp_invoke_task: invoke the specified task
 //
 // gtid: global thread ID of caller
 // task: the task to invoke
 // current_task: the task to resume after task invokation
 static void __kmp_invoke_task(kmp_int32 gtid, kmp_task_t *task,
                               kmp_taskdata_t *current_task) {
   kmp_taskdata_t *taskdata = KMP_TASK_TO_TASKDATA(task);