init.c

/*****************************************************************************
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/*********************************************************************/
/* Copyright 2009, 2010 The University of Texas at Austin.           */
/* All rights reserved.                                              */
/*                                                                   */
/* Redistribution and use in source and binary forms, with or        */
/* without modification, are permitted provided that the following   */
/* conditions are met:                                               */
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/*      copyright notice, this list of conditions and the following  */
/*      disclaimer.                                                  */
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/*      provided with the distribution.                              */
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/*********************************************************************/

#include "common.h"

#if defined(OS_LINUX) && defined(SMP)

#define _GNU_SOURCE

#include <sys/sysinfo.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <errno.h>
#include <sys/shm.h>
#include <fcntl.h>
#include <sched.h>
#include <dirent.h>
#include <dlfcn.h>
#include <unistd.h>
#include <string.h>

#if defined(BIGNUMA)
// max number of nodes as defined in numa.h
// max cpus as defined in most sched.h
// cannot use CPU_SETSIZE directly as some
// Linux distributors set it to 4096 
#define MAX_NODES	128
#define MAX_CPUS	1024
#else
#define MAX_NODES	16
#define MAX_CPUS	256
#endif

#define NCPUBITS        (8*sizeof(unsigned long))
#define MAX_BITMASK_LEN (MAX_CPUS/NCPUBITS)
#define CPUELT(cpu)	((cpu) / NCPUBITS)
#define CPUMASK(cpu)	((unsigned long) 1UL << ((cpu) % NCPUBITS))


#define SH_MAGIC	0x510510

#define CPUMAP_NAME	"/sys/devices/system/node/node%d/cpumap"
#define SHARE_NAME	"/sys/devices/system/cpu/cpu%d/cache/index%d/shared_cpu_map"
#define NODE_DIR	"/sys/devices/system/node"

//#undef DEBUG

/* Private variables */
typedef struct {
  unsigned long lock;
  unsigned int magic;
  unsigned int shmid;

  int num_nodes;
  int num_procs;
  int final_num_procs;
  unsigned long avail [MAX_BITMASK_LEN];
  int avail_count;
  unsigned long cpu_info   [MAX_CPUS];
  unsigned long node_info  [MAX_NODES][MAX_BITMASK_LEN];
  int cpu_use[MAX_CPUS];

} shm_t;

static cpu_set_t cpu_orig_mask[4];

static int  cpu_mapping[MAX_CPUS];
static int  node_mapping[MAX_CPUS * 4];
static int  cpu_sub_mapping[MAX_CPUS];
static int  disable_mapping;

/* Number of cores per nodes */
static int  node_cpu[MAX_NODES];
static int  node_equal = 0;

static shm_t *common = (void *)-1;
static int shmid, pshmid;
static void *paddr;

static unsigned long lprocmask[MAX_BITMASK_LEN], lnodemask;
static int lprocmask_count = 0;
static int numprocs = 1;
static int numnodes = 1;

#if 1
#define READ_CPU(x)   ( (x)        & 0xff)
#define READ_NODE(x)  (((x) >>  8) & 0xff)
#define READ_CORE(x)  (((x) >> 16) & 0xff)

#define WRITE_CPU(x)    (x)
#define WRITE_NODE(x)  ((x) <<  8)
#define WRITE_CORE(x)  ((x) << 16)
#else
#define READ_CPU(x)   ( (x)        & 0xff)
#define READ_CORE(x)  (((x) >>  8) & 0xff)
#define READ_NODE(x)  (((x) >> 16) & 0xff)

#define WRITE_CPU(x)    (x)
#define WRITE_CORE(x)  ((x) <<  8)
#define WRITE_NODE(x)  ((x) << 16)
#endif

static inline int popcount(unsigned long number) {

  int count = 0;

  while (number > 0) {
    if (number & 1) count ++;
    number >>= 1;
  }

  return count;
}

static inline int rcount(unsigned long number) {

  int count = -1;

  while ((number > 0) && ((number & 0)) == 0) {
    count ++;
    number >>= 1;
  }

  return count;
}

/***
  Known issue: The number of CPUs/cores should less
  than sizeof(unsigned long). On 64 bits, the limit
  is 64. On 32 bits, it is 32.
***/
static inline void get_cpumap(int node, unsigned long * node_info) {

  int infile;
  unsigned long affinity[32];
  char name[160];
  char cpumap[160];
  char *dummy;
  int i=0;
  int count=0;
  int k=0;

  sprintf(name, CPUMAP_NAME, node);

  infile = open(name, O_RDONLY);
  for(i=0; i<32; i++){
    affinity[i] = 0;
  }

  if (infile != -1) {

    read(infile, cpumap, sizeof(cpumap));

    for(i=0; i<160; i++){
      if(cpumap[i] == '\n')
	break;
      if(cpumap[i] != ','){
	name[k++]=cpumap[i];

	//Enough data for Hex
	if(k >= NCPUBITS/4){
	  affinity[count++] = strtoul(name, &dummy, 16);
	  k=0;
	}
      }

    }
    if(k!=0){
      name[k]='\0';
      affinity[count++] = strtoul(name, &dummy, 16);
      // k=0;
    }
    // 0-63bit -> node_info[0], 64-128bit -> node_info[1] ....
    // revert the sequence
    for(i=0; i<count && i<MAX_BITMASK_LEN; i++){
      node_info[i]=affinity[count-i-1];
    }
    close(infile);
  }

  return ;
}

static inline void get_share(int cpu, int level, unsigned long * share) {

  int infile;
  unsigned long affinity[32];
  char cpumap[160];
  char name[160];
  char *dummy;
  int count=0;
  int i=0,k=0;
  int bitmask_idx = 0;

  sprintf(name, SHARE_NAME, cpu, level);

  infile = open(name, O_RDONLY);

  //  Init share
  for(i=0; i<MAX_BITMASK_LEN; i++){
    share[i]=0;
  }
  bitmask_idx = CPUELT(cpu);
  share[bitmask_idx] = CPUMASK(cpu);

  if (infile != -1) {

    read(infile, cpumap, sizeof(cpumap));

    for(i=0; i<160; i++){
      if(cpumap[i] == '\n')
	break;
      if(cpumap[i] != ','){
	name[k++]=cpumap[i];

	//Enough data
	if(k >= NCPUBITS/4){
	  affinity[count++] = strtoul(name, &dummy, 16);
	  k=0;
	}
      }

    }
    if(k!=0){
      name[k]='\0';
      affinity[count++] = strtoul(name, &dummy, 16);
      // k=0;
    }
    // 0-63bit -> node_info[0], 64-128bit -> node_info[1] ....
    // revert the sequence
    for(i=0; i<count && i<MAX_BITMASK_LEN; i++){
      share[i]=affinity[count-i-1];
    }


    close(infile);
  }

  return ;
}

static int numa_check(void) {

  DIR *dp;
  struct dirent *dir;
  int node;
  int j;

  common -> num_nodes = 0;

  dp = opendir(NODE_DIR);

  if (dp == NULL) {
    common -> num_nodes = 1;
    return 0;
  }

  for (node = 0; node < MAX_NODES; node ++) {
    for (j = 0; j<MAX_BITMASK_LEN; j++) common -> node_info[node][j] = 0;
  }

  while ((dir = readdir(dp)) != NULL) {
    if (strncmp(dir->d_name, "node", 4)==0) {

      node = atoi(&dir -> d_name[4]);

      if (node > MAX_NODES) {
	fprintf(stderr, "\nOpenBLAS Warning : MAX_NODES (NUMA) is too small. Terminated.\n");
	exit(1);
      }

      common -> num_nodes ++;
      get_cpumap(node, common->node_info[node]);

    }
  }

  closedir(dp);

  if (common -> num_nodes == 1) return 1;

#ifdef DEBUG
  fprintf(stderr, "Numa found : number of Nodes = %2d\n", common -> num_nodes);

  for (node = 0; node < common -> num_nodes; node ++)
    fprintf(stderr, "MASK (%2d) : %08lx\n", node, common -> node_info[node][0]);
#endif

  return common -> num_nodes;
}

#if defined(__GLIBC_PREREQ)
#if !__GLIBC_PREREQ(2, 6)
int sched_getcpu(void)
{
int cpu;
FILE *fp = NULL;
if ( (fp = fopen("/proc/self/stat", "r")) == NULL)
   return -1;
if ( fscanf( fp, "%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%*s%d", &cpu) != 1) {
  fclose (fp);
  return -1;
  }
  fclose (fp);
  return(cpu);
}
#endif
#endif

static void numa_mapping(void) {

  int node, cpu, core;
  int i, j, h;
  unsigned long work, bit;
  int count = 0;
  int bitmask_idx = 0;
  int current_cpu;
  int current_node = 0;
  int cpu_count = 0;

  for (node = 0; node < common -> num_nodes; node ++) {
    core = 0;
    for (cpu = 0; cpu < common -> num_procs; cpu ++) {
      bitmask_idx = CPUELT(cpu);
      if (common -> node_info[node][bitmask_idx] & common -> avail[bitmask_idx] & CPUMASK(cpu)) {
	common -> cpu_info[count] = WRITE_CORE(core) | WRITE_NODE(node) | WRITE_CPU(cpu);
	count ++;
	core ++;
      }

    }
  }

#ifdef DEBUG
  fprintf(stderr, "\nFrom /sys ...\n\n");

  for (cpu = 0; cpu < count; cpu++)
    fprintf(stderr, "CPU (%2d) : %08lx\n", cpu, common -> cpu_info[cpu]);
#endif

  current_cpu = sched_getcpu();
  for (cpu = 0; cpu < count; cpu++) {
    if (READ_CPU(common -> cpu_info[cpu]) == current_cpu) {
      current_node = READ_NODE(common -> cpu_info[cpu]);
      break;
    }
  }
  for (i = 0; i < MAX_BITMASK_LEN; i++)
    cpu_count += popcount(common -> node_info[current_node][i] & common -> avail[i]);

  /*
   * If all the processes can be accommodated in the
   * in the current node itself, then bind to cores
   * from the current node only
   */
  if (numprocs <= cpu_count) {
    /*
     * First sort all the cores in order from the current node.
     * Then take remaining nodes one by one in order,
     * and sort their cores in order.
     */
    for (i = 0; i < count; i++) {
      for (j = 0; j < count - 1; j++) {
        int node_1, node_2;
        int core_1, core_2;
        int swap = 0;

        node_1 = READ_NODE(common -> cpu_info[j]);
        node_2 = READ_NODE(common -> cpu_info[j + 1]);
        core_1 = READ_CORE(common -> cpu_info[j]);
        core_2 = READ_CORE(common -> cpu_info[j + 1]);

        if (node_1 == node_2) {
          if (core_1 > core_2)
            swap = 1;
        } else {
          if ((node_2 == current_node) ||
              ((node_1 != current_node) && (node_1 > node_2)))
            swap = 1;
        }
        if (swap) {
          unsigned long temp;

          temp = common->cpu_info[j];
          common->cpu_info[j] = common->cpu_info[j + 1];
          common->cpu_info[j + 1] = temp;
        }
      }
    }
  } else {
    h = 1;

    while (h < count) h = 2 * h + 1;

    while (h > 1) {
      h /= 2;
      for (i = h; i < count; i++) {
        work = common -> cpu_info[i];
        bit  = CPU_ISSET(i, &cpu_orig_mask[0]);
        j = i - h;
        while (work < common -> cpu_info[j]) {
          common -> cpu_info[j + h] = common -> cpu_info[j];
          if (CPU_ISSET(j, &cpu_orig_mask[0])) {
            CPU_SET(j + h, &cpu_orig_mask[0]);
          } else {
            CPU_CLR(j + h, &cpu_orig_mask[0]);
          }
          j -= h;
          if (j < 0) break;
        }
        common -> cpu_info[j + h] = work;
        if (bit) {
          CPU_SET(j + h, &cpu_orig_mask[0]);
        } else {
          CPU_CLR(j + h, &cpu_orig_mask[0]);
        }

      }
    }
  }

#ifdef DEBUG
  fprintf(stderr, "\nSorting ...\n\n");

  for (cpu = 0; cpu < count; cpu++)
    fprintf(stderr, "CPUINFO (%2d) : %08lx (CPU=%3lu CORE=%3lu NODE=%3lu)\n", cpu, common -> cpu_info[cpu],
      READ_CPU(common -> cpu_info[cpu]),
      READ_CORE(common -> cpu_info[cpu]),
      READ_NODE(common -> cpu_info[cpu]));
#endif

}

static void disable_hyperthread(void) {

  unsigned long share[MAX_BITMASK_LEN];
  int cpu;
  int bitmask_idx = 0;
  int i=0, count=0;
  bitmask_idx = CPUELT(common -> num_procs);

  for(i=0; i< bitmask_idx; i++){
    common -> avail[count++] = 0xFFFFFFFFFFFFFFFFUL;
  }
  if(CPUMASK(common -> num_procs) != 1){
    common -> avail[count++] = CPUMASK(common -> num_procs) - 1;
  }
  common -> avail_count = count;

  /* if(common->num_procs > 64){ */
  /*   fprintf(stderr, "\nOpenBLAS Warning : The number of CPU/Cores(%d) is beyond the limit(64). Terminated.\n", common->num_procs); */
  /*   exit(1); */
  /* }else if(common->num_procs == 64){ */
  /*   common -> avail = 0xFFFFFFFFFFFFFFFFUL; */
  /* }else */
  /*   common -> avail = (1UL << common -> num_procs) - 1; */

#ifdef DEBUG
  fprintf(stderr, "\nAvail CPUs    : ");
  for(i=0; i<count; i++)
    fprintf(stderr, "%04lx ", common -> avail[i]);
  fprintf(stderr, ".\n");
#endif

  for (cpu = 0; cpu < common -> num_procs; cpu ++) {

    get_share(cpu, 1, share);

    //When the shared cpu are in different element of share & avail array, this may be a bug.
    for (i = 0; i < count ; i++){

      share[i] &= common->avail[i];

      if (popcount(share[i]) > 1) {

#ifdef DEBUG
	fprintf(stderr, "Detected Hyper Threading on CPU %4x; disabled CPU %04lx.\n",
		cpu, share[i] & ~(CPUMASK(cpu)));
#endif

	common -> avail[i] &= ~((share[i] & ~ CPUMASK(cpu)));
      }
    }
  }
}

static void disable_affinity(void) {
  int i=0;
  int bitmask_idx=0;
  int count=0;
#ifdef DEBUG
    fprintf(stderr, "Final all available CPUs  : %04lx.\n\n", common -> avail[0]);
    fprintf(stderr, "CPU mask                  : %04lx.\n\n", *(unsigned long *)&cpu_orig_mask[0]);
#endif

  /* if(common->final_num_procs > 64){ */
  /*   fprintf(stderr, "\nOpenBLAS Warining : The number of CPU/Cores(%d) is beyond the limit(64). Terminated.\n", common->final_num_procs); */
  /*   exit(1); */
  /* }else if(common->final_num_procs == 64){ */
  /*   lprocmask = 0xFFFFFFFFFFFFFFFFUL; */
  /* }else */
  /*   lprocmask = (1UL << common -> final_num_procs) - 1; */

  bitmask_idx = CPUELT(common -> final_num_procs);

  for(i=0; i< bitmask_idx; i++){
    lprocmask[count++] = 0xFFFFFFFFFFFFFFFFUL;
  }
  if(CPUMASK(common -> final_num_procs) != 1){
    lprocmask[count++] = CPUMASK(common -> final_num_procs) - 1;
  }
  lprocmask_count = count;

#ifndef USE_OPENMP
  for(i=0; i< count; i++){
    lprocmask[i] &= common->avail[i];
  }
#endif

#ifdef DEBUG
    fprintf(stderr, "I choose these CPUs  : %04lx.\n\n", lprocmask[0]);
#endif

}

static void setup_mempolicy(void) {

  int cpu, mynode, maxcpu;

  for (cpu = 0; cpu < MAX_NODES; cpu ++) node_cpu[cpu] = 0;

  maxcpu = 0;

  for (cpu = 0; cpu < numprocs; cpu ++) {
    mynode = READ_NODE(common -> cpu_info[cpu_sub_mapping[cpu]]);

    lnodemask |= (1UL << mynode);

    node_cpu[mynode] ++;

    if (maxcpu < node_cpu[mynode]) maxcpu = node_cpu[mynode];
  }

  node_equal = 1;

  for (cpu = 0; cpu < MAX_NODES; cpu ++) if ((node_cpu[cpu] != 0) && (node_cpu[cpu] != maxcpu)) node_equal = 0;

  if (lnodemask) {

#ifdef DEBUG
    fprintf(stderr, "Node mask = %lx\n", lnodemask);
#endif

    my_set_mempolicy(MPOL_INTERLEAVE, &lnodemask, sizeof(lnodemask) * 8);

    numnodes = popcount(lnodemask);
  }
}

static inline int is_dead(int id) {

  struct shmid_ds ds;

  return shmctl(id, IPC_STAT, &ds);
}

static int open_shmem(void) {

  int try = 0;

  int err = 0;
  
  do {

#if defined(BIGNUMA)
    // raised to 32768, enough for 128 nodes and 1024 cups
    shmid = shmget(SH_MAGIC, 32768, 0666);
#else
    shmid = shmget(SH_MAGIC, 4096, 0666);
#endif

    if (shmid == -1) {
#if defined(BIGNUMA)
      shmid = shmget(SH_MAGIC, 32768, IPC_CREAT | 0666);
#else
      shmid = shmget(SH_MAGIC, 4096, IPC_CREAT | 0666);
#endif
    }

    if (shmid == -1) err = errno;
    
    try ++;

  } while ((try < 10) && (shmid == -1));

  if (shmid == -1) {
    fprintf (stderr, "Obtaining shared memory segment failed in open_shmem: %s\n",strerror(err));
    fprintf (stderr, "Setting CPU affinity not possible without shared memory access.\n");
    return (1);
  }

  if (shmid != -1) {
    if ( (common = shmat(shmid, NULL, 0)) == (void*)-1) {
      perror ("Attaching shared memory segment failed in open_shmem");
      fprintf (stderr, "Setting CPU affinity not possible without shared memory access.\n");
      return (1);
    }
  }
#ifdef DEBUG
  fprintf(stderr, "Shared Memory id = %x  Address = %p\n", shmid, common);
#endif
  return (0);
}

static int create_pshmem(void) {

  pshmid = shmget(IPC_PRIVATE, 4096, IPC_CREAT | 0666);

  if (pshmid == -1) {
    perror ("Obtaining shared memory segment failed in create_pshmem");
    fprintf (stderr, "Setting CPU affinity not possible without shared memory access.\n");
    return(1);
  }
  
  if ( (paddr = shmat(pshmid, NULL, 0)) == (void*)-1) {
    perror ("Attaching shared memory segment failed in create_pshmem");
    fprintf (stderr, "Setting CPU affinity not possible without shared memory access.\n");
    return (1);
  }  
  
  if (shmctl(pshmid, IPC_RMID, 0) == -1) return (1);

#ifdef DEBUG
  fprintf(stderr, "Private Shared Memory id = %x  Address = %p\n", pshmid, paddr);
#endif
  return(0);
}

static void local_cpu_map(void) {

  int cpu, id, mapping;
  int bitmask_idx = 0;
  cpu = 0;
  mapping = 0;

  do {
    id   = common -> cpu_use[cpu];

    if (id > 0) {
      if (is_dead(id)) common -> cpu_use[cpu] = 0;
    }

    bitmask_idx = CPUELT(cpu);
    if ((common -> cpu_use[cpu] == 0) && (lprocmask[bitmask_idx] & CPUMASK(cpu))) {

      common -> cpu_use[cpu] = pshmid;
      cpu_mapping[mapping] = READ_CPU(common -> cpu_info[cpu]);
      cpu_sub_mapping[mapping] = cpu;

      mapping ++;
    }

    cpu ++;

  } while ((mapping < numprocs) && (cpu < common -> final_num_procs));

  disable_mapping = 0;

  if ((mapping < numprocs) || (numprocs == 1)) {
    for (cpu = 0; cpu < common -> final_num_procs; cpu ++) {
      if (common -> cpu_use[cpu] == pshmid) common -> cpu_use[cpu] = 0;
    }
    disable_mapping = 1;
  }

#ifdef DEBUG
  for (cpu = 0; cpu < numprocs; cpu ++) {
    fprintf(stderr, "Local Mapping  : %2d --> %2d (%2d)\n", cpu, cpu_mapping[cpu], cpu_sub_mapping[cpu]);
  }
#endif
}

/* Public Functions */

int get_num_procs(void)  { return numprocs; }
int get_num_nodes(void)  { return numnodes; }
int get_node_equal(void) {

  return (((blas_cpu_number % numnodes) == 0) && node_equal);

}

int gotoblas_set_affinity(int pos) {

  cpu_set_t cpu_mask;

  int mynode = 1;

  /* if number of threads is larger than initial condition */
  if (pos < 0) {
      sched_setaffinity(0, sizeof(cpu_orig_mask), &cpu_orig_mask[0]);
      return 0;
  }

  if (!disable_mapping) {

    mynode = READ_NODE(common -> cpu_info[cpu_sub_mapping[pos]]);

#ifdef DEBUG
    fprintf(stderr, "Giving Affinity[%4d   %3d] --> %3d  My node = %3d\n", getpid(), pos, cpu_mapping[pos], mynode);
#endif

    CPU_ZERO(&cpu_mask);
    CPU_SET (cpu_mapping[pos], &cpu_mask);

    sched_setaffinity(0, sizeof(cpu_mask), &cpu_mask);

    node_mapping[WhereAmI()] = mynode;

  }

  return mynode;
}

int get_node(void) {

  if (!disable_mapping) return node_mapping[WhereAmI()];

  return 1;
}

static int initialized = 0;

void gotoblas_affinity_init(void) {

  int cpu, num_avail;
#ifndef USE_OPENMP
  cpu_set_t cpu_mask;
#endif
  int i;

  if (initialized) return;

  initialized = 1;

  sched_getaffinity(0, sizeof(cpu_orig_mask), &cpu_orig_mask[0]);

#ifdef USE_OPENMP
  numprocs = 0;
#else
  numprocs = readenv_atoi("OPENBLAS_NUM_THREADS");
  if (numprocs == 0) numprocs = readenv_atoi("GOTO_NUM_THREADS");
#endif

  if (numprocs == 0) numprocs = readenv_atoi("OMP_NUM_THREADS");

  if (numprocs == 0) numprocs = readenv_atoi("OPENBLAS_DEFAULT_NUM_THREADS");

  numnodes = 1;

  if (numprocs == 1) {
    disable_mapping = 1;
    return;
  }

  if (create_pshmem() != 0) {
    disable_mapping = 1;
    return;
  }
  
  if (open_shmem() != 0) {
    disable_mapping = 1;
    return;
  }
  
  while ((common -> lock) && (common -> magic != SH_MAGIC)) {
    if (is_dead(common -> shmid)) {
      common -> lock = 0;
      common -> shmid = 0;
      common -> magic = 0;
    } else {
      YIELDING;
    }
  }

  blas_lock(&common -> lock);

  if ((common -> shmid) && is_dead(common -> shmid)) common -> magic = 0;

  common -> shmid = pshmid;

  if (common -> magic != SH_MAGIC) {

#if defined(__GLIBC_PREREQ)
#if __GLIBC_PREREQ(2, 7)
    cpu_set_t *cpusetp;
#else
    cpu_set_t cpuset;
#endif
#endif    
    int nums;
    int ret;

#ifdef DEBUG
    fprintf(stderr, "Shared Memory Initialization.\n");
#endif

    //returns the number of processors which are currently online

    nums = sysconf(_SC_NPROCESSORS_CONF);

#if !defined(__GLIBC_PREREQ)
    common->num_procs = nums >0 ? nums : 2;
#else

#if !__GLIBC_PREREQ(2, 3)
    common->num_procs = nums >0 ? nums : 2;
#elif __GLIBC_PREREQ(2, 7)
    cpusetp = CPU_ALLOC(nums>0? nums:1024);
    if (cpusetp == NULL) {
        common->num_procs = nums>0 ? nums: 2;
    } else {
        size_t size;
        size = CPU_ALLOC_SIZE(nums>0? nums: 1024);
        ret = sched_getaffinity(0,size,cpusetp);
        if (ret!=0)
            common->num_procs = nums >0 ? nums : 1;
        else
            common->num_procs = CPU_COUNT_S(size,cpusetp);
    }
    CPU_FREE(cpusetp);
#else
    ret = sched_getaffinity(0,sizeof(cpu_set_t), &cpuset);
    if (ret!=0) {
        common->num_procs = nums >0 ? nums : 2;
    } else {
#if !__GLIBC_PREREQ(2, 6)
    int i;
    int n = 0;
    for (i=0;i<(nums >0 ?nums:1024) ;i++)
        if (CPU_ISSET(i,&cpuset)) n++;
    common->num_procs = n;
    }
#else
    common->num_procs = CPU_COUNT(&cpuset);
    }
#endif

#endif
#endif
    if(common -> num_procs > MAX_CPUS) {
      fprintf(stderr, "\nOpenBLAS Warning : The number of CPU/Cores(%d) is beyond the limit(%d). Terminated.\n", common->num_procs, MAX_CPUS);
      exit(1);
    }

    for (cpu = 0; cpu < common -> num_procs; cpu++) common -> cpu_info[cpu] = cpu;

    numa_check();

    disable_hyperthread();

    if (common -> num_nodes > 1) numa_mapping();

    common -> final_num_procs = 0;
    for(i = 0; i < common -> avail_count; i++) common -> final_num_procs += rcount(common -> avail[i]) + 1;   //Make the max cpu number. 

    for (cpu = 0; cpu < common -> final_num_procs; cpu ++) common -> cpu_use[cpu] =  0;

    common -> magic = SH_MAGIC;

  }

  disable_affinity();

  num_avail = 0;
  for(i=0; i<lprocmask_count; i++) num_avail += popcount(lprocmask[i]);

  if ((numprocs <= 0) || (numprocs > num_avail)) numprocs = num_avail;

#ifdef DEBUG
  fprintf(stderr, "Number of threads = %d\n", numprocs);
#endif

  local_cpu_map();

  blas_unlock(&common -> lock);

#ifndef USE_OPENMP
  if (!disable_mapping) {

#ifdef DEBUG
    fprintf(stderr, "Giving Affinity[%3d] --> %3d\n", 0, cpu_mapping[0]);
#endif

    CPU_ZERO(&cpu_mask);
    CPU_SET (cpu_mapping[0], &cpu_mask);

    sched_setaffinity(0, sizeof(cpu_mask), &cpu_mask);

    node_mapping[WhereAmI()] = READ_NODE(common -> cpu_info[cpu_sub_mapping[0]]);

    setup_mempolicy();

    if (readenv_atoi("OPENBLAS_MAIN_FREE") || readenv_atoi("GOTOBLAS_MAIN_FREE")) {
      sched_setaffinity(0, sizeof(cpu_orig_mask), &cpu_orig_mask[0]);
    }

  }
#endif

#ifdef DEBUG
  fprintf(stderr, "Initialization is done.\n");
#endif
}

void gotoblas_affinity_quit(void) {

  int i;
  struct shmid_ds ds;

#ifdef DEBUG
  fprintf(stderr, "Terminating ..\n");
#endif

  if ((numprocs == 1) || (initialized == 0)) return;

  if (!disable_mapping) {

    blas_lock(&common -> lock);

    for (i = 0; i < numprocs; i ++) common -> cpu_use[cpu_mapping[i]] = -1;

    blas_unlock(&common -> lock);

  }

  shmctl(shmid, IPC_STAT, &ds);

  if (ds.shm_nattch == 1) shmctl(shmid, IPC_RMID, 0);

  shmdt(common);

  shmdt(paddr);

  initialized = 0;
}

#else

void gotoblas_affinity_init(void) {};

void gotoblas_set_affinity(int threads) {};

void gotoblas_set_affinity2(int threads) {};

void gotoblas_affinity_reschedule(void) {};

int get_num_procs(void) { int num = sysconf(_SC_NPROCESSORS_CONF); return (nums >0 ? nums : 2); }

int get_num_nodes(void) { return 1; }

int get_node(void) { return 1;}
#endif