hphp/util/numa.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16 #pragma once
  17
  18 #include <atomic>
  19
  20 #include <cstdlib>
  21 #ifdef HAVE_NUMA
  22 #include <vector>
  23 #include <numa.h>
  24 #endif
  25
  26 namespace HPHP {
  27 // numa_num_nodes and numa_node_set are always defined. They are initialized to
  28 // 1 (which is the value when libnuma isn't used).
  29 extern uint32_t numa_num_nodes;
  30 extern uint32_t numa_node_set;
  31
  32 #ifdef HAVE_NUMA
  33
  34 extern uint32_t numa_node_mask;
  35 extern std::vector<bitmask*> node_to_cpu_mask;
  36 extern bool use_numa;
  37
  38 /*
  39  * init_numa() is called very early during process initialization, before
  40  * parsing runtime options. It initializes `numa_num_nodes`, `numa_node_set`,
  41  * and `numa_node_mask`, when NUMA APIs are usable.
  42  */
  43 void init_numa();
  44
  45 /*
  46  * enable_numa() is called after parsing runtime options. It initializes
  47  * `use_numa`, which is used to decide whether we actually call NUMA APIs. Note
  48  * that on single-node systems, we don't set use_numa.
  49  */
  50 void enable_numa();
  51
  52 /*
  53  * Determine the next NUMA node according to state maintained in `curr_node`.
  54  */
  55 uint32_t next_numa_node(std::atomic<uint32_t>& curr_node);
  56 /*
  57  * The number of numa nodes in the system
  58  */
  59 inline uint32_t num_numa_nodes() {
  60   return use_numa ? numa_num_nodes : 1;
  61 }
  62 /*
  63  * Enable numa interleaving for the specified address range
  64  */
  65 void numa_interleave(void* start, size_t size);
  66 /*
  67  * Allocate the specified address range on the given node
  68  */
  69 void numa_bind_to(void* start, size_t size, uint32_t node);
  70 /*
  71  * Return true if node is part of the allowed set of numa nodes
  72  */
  73 inline bool numa_node_allowed(uint32_t node) {
  74   if (numa_node_set == 0) return true;
  75   return numa_node_set & (1u << node);
  76 }
  77
  78 #else // HAVE_NUMA undefined
  79
  80 inline void init_numa() {}
  81 inline void enable_numa() {}
  82 inline constexpr uint32_t next_numa_node(std::atomic<uint32_t>& curr_node) {
  83   return 0;
  84 }
  85 inline constexpr uint32_t num_numa_nodes() { return 1; }
  86 inline void numa_interleave(void* start, size_t size) {}
  87 inline void numa_bind_to(void* start, size_t size, uint32_t node) {}
  88 inline constexpr bool numa_node_allowed(int node) { return true; }
  89
  90 #endif
  91
  92 } // namespace HPHP