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 #ifndef incl_HPHP_UTIL_NUMA_H
  17 #define incl_HPHP_UTIL_NUMA_H
  18
  19 #include <atomic>
  20
  21 #include <cstdlib>
  22 #ifdef HAVE_NUMA
  23 #include <vector>
  24 #include <numa.h>
  25 #endif
  26
  27 namespace HPHP {
  28 // numa_num_nodes and numa_node_set are always defined. They are initialized to
  29 // 1 (which is the value when libnuma isn't used).
  30 extern uint32_t numa_num_nodes;
  31 extern uint32_t numa_node_set;
  32
  33 #ifdef HAVE_NUMA
  34
  35 extern uint32_t numa_node_mask;
  36 extern std::vector<bitmask*> node_to_cpu_mask;
  37 extern bool use_numa;
  38
  39 /*
  40  * init_numa() is called very early during process initialization, before
  41  * parsing runtime options. It initializes `numa_num_nodes`, `numa_node_set`,
  42  * and `numa_node_mask`, when NUMA APIs are usable.
  43  */
  44 void init_numa();
  45
  46 /*
  47  * enable_numa() is called after parsing runtime options. It initializes
  48  * `use_numa`, which is used to decide whether we actually call NUMA APIs. Note
  49  * that on single-node systems, we don't set use_numa.
  50  */
  51 void enable_numa();
  52
  53 /*
  54  * Determine the next NUMA node according to state maintained in `curr_node`.
  55  */
  56 uint32_t next_numa_node(std::atomic<uint32_t>& curr_node);
  57 /*
  58  * The number of numa nodes in the system
  59  */
  60 inline uint32_t num_numa_nodes() {
  61   return use_numa ? numa_num_nodes : 1;
  62 }
  63 /*
  64  * Enable numa interleaving for the specified address range
  65  */
  66 void numa_interleave(void* start, size_t size);
  67 /*
  68  * Allocate the specified address range on the given node
  69  */
  70 void numa_bind_to(void* start, size_t size, uint32_t node);
  71 /*
  72  * Return true if node is part of the allowed set of numa nodes
  73  */
  74 inline bool numa_node_allowed(uint32_t node) {
  75   if (numa_node_set == 0) return true;
  76   return numa_node_set & (1u << node);
  77 }
  78
  79 #else // HAVE_NUMA undefined
  80
  81 inline void init_numa() {}
  82 inline void enable_numa() {}
  83 inline constexpr uint32_t next_numa_node(std::atomic<uint32_t>& curr_node) {
  84   return 0;
  85 }
  86 inline constexpr uint32_t num_numa_nodes() { return 1; }
  87 inline void numa_interleave(void* start, size_t size) {}
  88 inline void numa_bind_to(void* start, size_t size, uint32_t node) {}
  89 inline constexpr bool numa_node_allowed(int node) { return true; }
  90
  91 #endif
  92
  93 } // namespace HPHP
  94 #endif