libgomp/config/rtems/proc.c

   1 /* Copyright (C) 2015 Free Software Foundation, Inc.
   2    Contributed by Sebastian Huber <sebastian.huber@embedded-brains.de>.
   3
   4    This file is part of the GNU Offloading and Multi Processing Library
   5    (libgomp).
   6
   7    Libgomp is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    Libgomp is distributed in the hope that it will be useful, but WITHOUT ANY
  13    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
  14    FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15    more details.
  16
  17    Under Section 7 of GPL version 3, you are granted additional
  18    permissions described in the GCC Runtime Library Exception, version
  19    3.1, as published by the Free Software Foundation.
  20
  21    You should have received a copy of the GNU General Public License and
  22    a copy of the GCC Runtime Library Exception along with this program;
  23    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24    <http://www.gnu.org/licenses/>.  */
  25
  26 /* This file contains RTEMS specific routines related to counting
  27    online processors and dynamic load balancing.  */
  28
  29 #include "libgomp.h"
  30 #include "pool.h"
  31 #include <errno.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <unistd.h>
  35
  36 struct gomp_thread_pool_reservoir **gomp_thread_pool_reservoirs;
  37
  38 __thread struct gomp_tls_rtems_data gomp_tls_rtems_data;
  39
  40 static void
  41 allocate_thread_pool_reservoirs (void)
  42 {
  43   struct gomp_thread_pool_reservoir **reservoirs;
  44   size_t size = _Sched_Count () * sizeof (*reservoirs);
  45   reservoirs = gomp_malloc (size);
  46   gomp_thread_pool_reservoirs = reservoirs;
  47   memset (reservoirs, 0, size);
  48 }
  49
  50 static void
  51 allocate_thread_pool_reservoir (unsigned long count, unsigned long scheduler)
  52 {
  53   struct gomp_thread_pool_reservoir *res;
  54   struct gomp_thread_pool *pools;
  55   unsigned long i;
  56   size_t size;
  57
  58   res = gomp_thread_pool_reservoirs[scheduler];
  59   if (res != NULL)
  60     gomp_fatal ("Multiple thread pool reservoir initialization");
  61   size = sizeof (*res) + count * (sizeof(pools) + sizeof(*pools));
  62   pools = gomp_malloc (size);
  63   memset (pools, 0, size);
  64   res = (struct gomp_thread_pool_reservoir *) (pools + count);
  65   res->index = count;
  66   gomp_sem_init (&res->available, count);
  67   gomp_mutex_init (&res->lock);
  68   for (i = 0; i < count; ++i)
  69     res->pools[i] = &pools[i];
  70   gomp_thread_pool_reservoirs[scheduler] = res;
  71 }
  72
  73 static char *
  74 parse_thread_pools (char *env, unsigned long *count, unsigned long *scheduler)
  75 {
  76   size_t len;
  77   int i;
  78
  79   if (*env == ':')
  80     ++env;
  81
  82   errno = 0;
  83   *count = strtoul (env, &env, 10);
  84   if (errno != 0)
  85     gomp_fatal ("Invalid thread pool count");
  86
  87   if (*env != '@')
  88     gomp_fatal ("Invalid thread pool scheduler prefix");
  89   ++env;
  90
  91   len = 0;
  92   while (env[len] != '\0' && env[len] != ':')
  93     ++len;
  94   i = _Sched_Name_to_index (env, len);
  95   if (i < 0)
  96     gomp_fatal ("Invalid thread pool scheduler");
  97   *scheduler = i;
  98   env += len;
  99
 100   return env;
 101 }
 102
 103 static void
 104 init_thread_pool_reservoirs (void)
 105 {
 106   char *env = getenv ("GOMP_RTEMS_THREAD_POOLS");
 107   if (env != NULL)
 108     {
 109       allocate_thread_pool_reservoirs ();
 110       while (*env != '\0')
 111         {
 112           unsigned long count;
 113           unsigned long scheduler;
 114           env = parse_thread_pools (env, &count, &scheduler);
 115           allocate_thread_pool_reservoir (count, scheduler);
 116         }
 117     }
 118 }
 119
 120 void
 121 gomp_init_num_threads (void)
 122 {
 123   gomp_global_icv.nthreads_var = omp_get_num_procs();
 124   init_thread_pool_reservoirs ();
 125 }
 126
 127 unsigned
 128 gomp_dynamic_max_threads (void)
 129 {
 130   unsigned n_onln = (unsigned) omp_get_num_procs();
 131   unsigned nthreads_var = gomp_icv (false)->nthreads_var;
 132
 133   if (n_onln > nthreads_var)
 134     return nthreads_var;
 135   else
 136     return n_onln;
 137 }
 138
 139 int
 140 omp_get_num_procs (void)
 141 {
 142   return sysconf (_SC_NPROCESSORS_ONLN);
 143 }
 144
 145 ialias (omp_get_num_procs)