/*
   Copyright (c) 2010, 2021, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License, version 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA
*/

#include <NdbNuma.h>
#include <ndb_global.h>

static int NDB_TRACE_NUMA = 0;

#if defined HAVE_DLFCN_H && defined HAVE_DLOPEN
#include <dlfcn.h>

/**
 * Load libnuma using dlopen, not have to put link dependency on it...
 * - handle fact that there are 2 versions of libnuma...
 *   use existance of symbol "numa_all_nodes_ptr" to use v2 abi
 */
struct bitmask;
extern "C"
{
  typedef int (* fun0)(void);
  typedef void (* fun1)(struct bitmask*);
  typedef void (* fun2)(int);
  typedef int (* fun3)(int node, unsigned long * bug, int buflen);
  typedef bitmask * (* fun4)();
  typedef void (* fun5)(struct bitmask*);
  typedef bitmask * (* fun6)(struct bitmask*);
};

class NdbNuma
{
public:
  NdbNuma() { handle = 0;}
  ~NdbNuma() { if (handle) dlclose(handle); }

  int open();
  int build_cputonodemap();

  void * handle;
  fun0 numa_available;

  fun0 numa_max_node;
  fun0 numa_max_possible_node;
  fun1 numa_set_interleave_mask;
  fun2 numa_set_strict;
  fun3 numa_node_to_cpus;
  fun4 numa_allocate_nodemask;
  fun5 numa_bitmask_free;
  fun6 numa_bitmask_setall;

  struct bitmask * numa_all_nodes;
  struct bitmask * numa_all_nodes_ptr;
};

static
void*
my_dlopen(const char * name)
{
  void * p = dlopen(name, RTLD_LAZY);
  if (NDB_TRACE_NUMA)
  {
    if (p == 0)
      printf("info: failed to load %s\n", name);
    else
      printf("info: loaded %s\n", name);
  }
  return p;
}

static
void*
my_dlsym(void * handle, const char * name)
{
  void * p = dlsym(handle, name);
  if (NDB_TRACE_NUMA)
  {
    if (p != 0)
    {
      printf("info: %s OK\n", name);
    }
    else
    {
      printf("info: %s NOT FOUND\n", name);
    }
  }
  return p;
}

int
NdbNuma::open()
{
  handle = my_dlopen("libnuma.so");
  if (handle == 0)
  {
    handle = my_dlopen("libnuma.so.1");
  }
  if (handle == 0)
  {
    return -1;
  }

  numa_available = (fun0)my_dlsym(handle, "numa_available");
  if (numa_available == 0)
  {
    goto fail;
  }

  if ((* numa_available)() == -1)
  {
    if (NDB_TRACE_NUMA)
    {
      printf("info: numa_available() returns -1 => no numa support\n");
    }
    goto fail;
  }

  numa_max_node = (fun0)my_dlsym(handle, "numa_max_node");
  numa_set_interleave_mask = (fun1)my_dlsym(handle, "numa_set_interleave_mask");
  numa_set_strict = (fun2)my_dlsym(handle, "numa_set_strict");
  numa_node_to_cpus = (fun3)my_dlsym(handle, "numa_node_to_cpus");
  numa_all_nodes = (struct bitmask*)my_dlsym(handle, "numa_all_nodes");
  numa_all_nodes_ptr = (struct bitmask*)my_dlsym(handle, "numa_all_nodes_ptr");
  numa_allocate_nodemask = (fun4)my_dlsym(handle, "numa_allocate_nodemask");
  numa_bitmask_free = (fun5)my_dlsym(handle, "numa_bitmask_free");
  numa_bitmask_setall = (fun6)my_dlsym(handle, "numa_bitmask_setall");


  return 0;
fail:
  dlclose(handle);
  handle = 0;
  return -1;
}

static
bool
bit_is_set(unsigned long * mask, int bit)
{
  int n = bit / (8 * sizeof(unsigned long));
  int b = bit % (8 * sizeof(unsigned long));
  return (mask[n] & (1UL << b)) != 0;
}

int
NdbNuma::build_cputonodemap()
{
  int len = 512;
  unsigned long * buf = (unsigned long*)malloc(len);
  if (buf == 0)
    return -1;

  int m = (* numa_max_node)();
  for (int i = 0; i <= m; i++)
  {
retry:
    int r = (* numa_node_to_cpus)(i, buf, len);
    if (r == -1)
    {
      if (errno != ERANGE)
        goto fail;

      len = len + 512;
      if (len > 4096)
        goto fail;

      void * p = realloc(buf, len);
      if (p == 0)
        goto fail;

      buf = (unsigned long*)p;
      goto retry;
    }
    printf("node %d cpu(s): ", i);
    for (int j = 0; j<8*len;j++)
      if (bit_is_set(buf, j))
        printf("%d ", j);
    printf("\n");
  }
  free(buf);
  return 0;
fail:
  free(buf);
  return -1;
}

extern "C"
int
NdbNuma_setInterleaved()
{
  NdbNuma numa;
  if (numa.open() == -1)
    return -1;

  if (numa.numa_set_interleave_mask == 0)
    return -1;

  if (numa.numa_all_nodes_ptr != 0)
  {
    /**
     * libnuma v2
     */
    if (numa.numa_allocate_nodemask != 0 &&
        numa.numa_bitmask_setall != 0 &&
        numa.numa_bitmask_free != 0)
    {
      struct bitmask * bm = (* numa.numa_allocate_nodemask)();
      if (bm != 0)
      {
        (* numa.numa_bitmask_setall)(bm);
        (* numa.numa_set_interleave_mask)(bm);
        (* numa.numa_bitmask_free)(bm);
      }
      else
      {
        return -1;
      }
    }
    else
    {
      return -1;
    }
  }
  else if (numa.numa_all_nodes != 0)
  {
    /**
     * libnuma v1
     */
    (* numa.numa_set_interleave_mask)(numa.numa_all_nodes);
  }
  else
  {
    return -1;
  }

  return 0;
}

#else
extern "C"
int
NdbNuma_setInterleaved()
{
  return -1;
}

extern "C"
int
NdbNuma_setInterleavedOnCpus(unsigned cpu[], unsigned len)
{
  return -1;
}
#endif

#ifdef TEST_NDBNUMA
#include <NdbTap.hpp>

TAPTEST(SetInterleaved)
{
  NDB_TRACE_NUMA = 1;
  NdbNuma_setInterleaved();
  return 1; // OK
}
#endif