Provided by: libnuma-dev_2.0.8~rc3-1_amd64 bug

NAME

       numa - NUMA policy library

SYNOPSIS

       #include <numa.h>

       cc ... -lnuma

       int numa_available(void);

       int numa_max_possible_node(void);
       int numa_num_possible_nodes();

       int numa_max_node(void);
       int numa_num_configured_nodes();
       struct bitmask *numa_get_mems_allowed(void);

       int numa_num_configured_cpus(void);
       struct bitmask *numa_all_nodes_ptr;
       struct bitmask *numa_no_nodes_ptr;
       struct bitmask *numa_all_cpus_ptr;

       int numa_num_task_cpus();
       int numa_num_task_nodes();

       int numa_parse_bitmap(char *line , struct bitmask *mask);
       struct bitmask *numa_parse_nodestring(char *string);
       struct bitmask *numa_parse_cpustring(char *string);

       long numa_node_size(int node, long *freep);
       long long numa_node_size64(int node, long long *freep);

       int numa_preferred(void);
       void numa_set_preferred(int node);
       int numa_get_interleave_node(void);
       struct bitmask *numa_get_interleave_mask(void);
       void numa_set_interleave_mask(struct bitmask *nodemask);
       void numa_interleave_memory(void *start, size_t size, struct bitmask *nodemask);
       void numa_bind(struct bitmask *nodemask);
       void numa_set_localalloc(void);
       void numa_set_membind(struct bitmask *nodemask);
       struct bitmask *numa_get_membind(void);

       void *numa_alloc_onnode(size_t size, int node);
       void *numa_alloc_local(size_t size);
       void *numa_alloc_interleaved(size_t size);
       void   *numa_alloc_interleaved_subset(size_t   size,    struct  bitmask  *nodemask);  void
       *numa_alloc(size_t size);
       void *numa_realloc(void *old_addr, size_t old_size, size_t new_size);
       void numa_free(void *start, size_t size);

       int numa_run_on_node(int node);
       int numa_run_on_node_mask(struct bitmask *nodemask);
       struct bitmask *numa_get_run_node_mask(void);

       void numa_tonode_memory(void *start, size_t size, int node);
       void numa_tonodemask_memory(void *start, size_t size, struct bitmask *nodemask);
       void numa_setlocal_memory(void *start, size_t size);
       void numa_police_memory(void *start, size_t size);
       void numa_set_bind_policy(int strict);
       void numa_set_strict(int strict);

       int numa_distance(int node1, int node2);

       int numa_sched_getaffinity(pid_t pid, struct bitmask *mask);
       int numa_sched_setaffinity(pid_t pid, struct bitmask *mask);
       int numa_node_to_cpus(int node, struct bitmask *mask);
       int numa_node_of_cpu(int cpu);

       struct bitmask *numa_allocate_cpumask();

       void numa_free_cpumask();
       struct bitmask *numa_allocate_nodemask();

       void numa_free_nodemask();
       struct bitmask *numa_bitmask_alloc(unsigned int n);
       struct bitmask *numa_bitmask_clearall(struct bitmask *bmp);
       struct bitmask *numa_bitmask_clearbit(struct bitmask *bmp, unsigned int n);
       int numa_bitmask_equal(const struct bitmask *bmp1, const struct bitmask *bmp2);
       void numa_bitmask_free(struct bitmask *bmp);
       int numa_bitmask_isbitset(const struct bitmask *bmp, unsigned int n);
       unsigned int numa_bitmask_nbytes(struct bitmask *bmp);
       struct bitmask *numa_bitmask_setall(struct bitmask *bmp);
       struct bitmask *numa_bitmask_setbit(struct bitmask *bmp, unsigned int n);
       void copy_bitmask_to_nodemask(struct bitmask *bmp, nodemask_t *nodemask)
       void copy_nodemask_to_bitmask(nodemask_t *nodemask, struct bitmask *bmp)
       void copy_bitmask_to_bitmask(struct bitmask *bmpfrom, struct bitmask *bmpto)
       unsigned int numa_bitmask_weight(const struct bitmask *bmp )

       int numa_move_pages(int pid, unsigned long count, void  **pages,  const  int  *nodes,  int
       *status, int flags);
       int numa_migrate_pages(int pid, struct bitmask *fromnodes, struct bitmask *tonodes);

       void numa_error(char *where);

       extern int numa_exit_on_error;
       extern int numa_exit_on_warn;
       void numa_warn(int number, char *where, ...);

DESCRIPTION

       The  libnuma library offers a simple programming interface to the NUMA (Non Uniform Memory
       Access) policy supported by the Linux kernel. On a NUMA  architecture  some  memory  areas
       have different latency or bandwidth than others.

       Available  policies  are  page  interleaving (i.e., allocate in a round-robin fashion from
       all, or a subset, of the nodes on the system), preferred node allocation (i.e., preferably
       allocate  on a particular node), local allocation (i.e., allocate on the node on which the
       task is currently executing), or allocation only on specific nodes (i.e., allocate on some
       subset of the available nodes).  It is also possible to bind tasks to specific nodes.

       Numa  memory allocation policy may be specified as a per-task attribute, that is inherited
       by children tasks and processes, or as an attribute of a range of process virtual  address
       space.   Numa memory policies specified for a range of virtual address space are shared by
       all tasks in the process.  Further more, memory policies specified for a range of a shared
       memory attached using shmat(2) or mmap(2) from shmfs/hugetlbfs are shared by all processes
       that attach to that region.  Memory policies for shared  disk  backed  file  mappings  are
       currently ignored.

       The  default  memory allocation policy for tasks and all memory range is local allocation.
       This assumes that no ancestor has installed a non-default policy.

       For setting a specific policy globally for all memory allocations in  a  process  and  its
       children  it  is  easiest  to  start  it with the numactl(8) utility. For more finegrained
       policy inside an application this library can be used.

       All numa memory allocation policy only takes effect when a page is actually  faulted  into
       the  address  space  of a process by accessing it. The numa_alloc_* functions take care of
       this automatically.

       A node is defined as an area where all memory has the same speed as seen from a particular
       CPU.  A node can contain multiple CPUs.  Caches are ignored for this definition.

       Most  functions in this library are only concerned about numa nodes and their memory.  The
       exceptions   to   this   are:   numa_node_to_cpus(),   numa_node_of_cpu(),    numa_bind(),
       numa_run_on_node(), numa_run_on_node_mask() and numa_get_run_node_mask().  These functions
       deal with the CPUs associated with numa  nodes.   See  the  descriptions  below  for  more
       information.

       Some  of  these  functions accept or return a pointer to struct bitmask.  A struct bitmask
       controls a bit map of arbitrary length containing a  bit  representation  of  nodes.   The
       predefined  variable  numa_all_nodes_ptr points to a bit mask that has all available nodes
       set; numa_no_nodes_ptr points to the empty set.

       Before any other calls in this library can be used numa_available() must be called. If  it
       returns -1, all other functions in this library are undefined.

       numa_max_possible_node()  returns the number of the highest possible node in a system.  In
       other words, the size of a kernel type nodemask_t (in bits) minus 1.  This number  can  be
       gotten by calling numa_num_possible_nodes() and subtracting 1.

       numa_num_possible_nodes() returns the size of kernel's node mask (kernel type nodemask_t).
       In other words, large enough to represent the maximum number of nodes that the kernel  can
       handle.  This  will  match  the  kernel's  MAX_NUMNODES value.  This count is derived from
       /proc/self/status, field Mems_allowed.

       numa_max_node() returns the highest node number available on the current system.  (See the
       node numbers in /sys/devices/system/node/ ).  Also see numa_num_configured_nodes().

       numa_num_configured_nodes()  returns  the number of memory nodes in the system. This count
       includes any nodes that are currently disabled.  This  count  is  derived  from  the  node
       numbers  in  /sys/devices/system/node.  (Depends  on the kernel being configured with /sys
       (CONFIG_SYSFS)).

       numa_get_mems_allowed() returns the mask of nodes from which the  process  is  allowed  to
       allocate  memory  in  it's current cpuset context.  Any nodes that are not included in the
       returned bitmask will be ignored in any of the following libnuma memory policy calls.

       numa_num_configured_cpus() returns the number of cpus in the system.  This count  includes
       any  cpus  that  are  currently  disabled.  This  count is derived from the cpu numbers in
       /sys/devices/system/cpu. If the kernel is configured without /sys (CONFIG_SYSFS=n) then it
       falls back to using the number of online cpus.

       numa_all_nodes_ptr  points  to  a  bitmask  that  is  allocated  by  the library with bits
       representing all nodes on which the calling task may allocate memory.  This set may be  up
       to  all  nodes  on  the  system, or up to the nodes in the current cpuset.  The bitmask is
       allocated by a call to numa_allocate_nodemask() using size numa_max_possible_node().   The
       set  of nodes to record is derived from /proc/self/status, field "Mems_allowed".  The user
       should not alter this bitmask.

       numa_no_nodes_ptr points to a bitmask that is  allocated  by  the  library  and  left  all
       zeroes.   The  bitmask  is  allocated  by  a  call  to numa_allocate_nodemask() using size
       numa_max_possible_node().  The user should not alter this bitmask.

       numa_all_cpus_ptr points to  a  bitmask  that  is  allocated  by  the  library  with  bits
       representing  all  cpus  on which the calling task may execute.  This set may be up to all
       cpus on the system, or up to the cpus in the current cpuset.  The bitmask is allocated  by
       a call to numa_allocate_cpumask() using size numa_num_possible_cpus().  The set of cpus to
       record is derived from /proc/self/status, field "Cpus_allowed".  The user should not alter
       this bitmask.

       numa_num_task_cpus()  returns  the number of cpus that the calling task is allowed to use.
       This count is derived from the map /proc/self/status, field "Cpus_allowed". Also  see  the
       bitmask numa_all_cpus_ptr.

       numa_num_task_nodes()  returns the number of nodes on which the calling task is allowed to
       allocate  memory.   This  count  is  derived  from  the   map   /proc/self/status,   field
       "Mems_allowed".  Also see the bitmask numa_all_nodes_ptr.

       numa_parse_bitmap()  parses  line  ,  which  is  a  character  string  such  as  found  in
       /sys/devices/system/node/nodeN/cpumap into a bitmask structure.  The string  contains  the
       hexadecimal   representation   of   a   bit  map.   The  bitmask  may  be  allocated  with
       numa_allocate_cpumask().  Returns  0 on success.  Returns -1 on failure.  This function is
       probably of little use to a user application, but it is used by libnuma internally.

       numa_parse_nodestring()  parses a character string list of nodes into a bit mask.  The bit
       mask is allocated by numa_allocate_nodemask().  The string is a  comma-separated  list  of
       node  numbers  or  node  ranges.   A leading ! can be used to indicate "not" this list (in
       other words, all nodes except this list), and a leading + can be used to indicate that the
       node  numbers  in  the list are relative to the task's cpuset.  The string can be "all" to
       specify all ( numa_num_task_nodes() ) nodes.  Node numbers are limited by  the  number  in
       the system.  See numa_max_node() and numa_num_configured_nodes().
       Examples:  1-5,7,10   !4-5   +0-3
       If  the  string  is  of 0 length, bitmask numa_no_nodes_ptr is returned.  Returns 0 if the
       string is invalid.

       numa_parse_cpustring() parses a character string list of cpus into a bit  mask.   The  bit
       mask is allocated by numa_allocate_cpumask().  The string is a comma-separated list of cpu
       numbers or cpu ranges.  A leading ! can be used to indicate  "not"  this  list  (in  other
       words,  all  cpus  except this list), and a leading + can be used to indicate that the cpu
       numbers in the list are relative to the task's cpuset.  The string can be "all" to specify
       all  (  numa_num_task_cpus() ) cpus.  Cpu numbers are limited by the number in the system.
       See numa_num_task_cpus() and numa_num_configured_cpus().
       Examples:  1-5,7,10   !4-5   +0-3
       Returns 0 if the string is invalid.

       numa_node_size() returns the memory size of a node. If the argument freep is not NULL,  it
       used to return the amount of free memory on the node.  On error it returns -1.

       numa_node_size64()  works  the  same  as numa_node_size() except that it returns values as
       long long instead of long.  This is useful on 32-bit architectures with large nodes.

       numa_preferred() returns the preferred node of the current task.   This  is  the  node  on
       which the kernel preferably allocates memory, unless some other policy overrides this.

       numa_set_preferred()  sets  the  preferred  node for the current task to node.  The system
       will attempt to allocate memory from the preferred node, but will fall back to other nodes
       if  no  memory  is  available  on  the  the preferred node.  Passing a node of -1 argument
       specifies local allocation and is equivalent to calling numa_set_localalloc().

       numa_get_interleave_mask() returns the  current  interleave  mask  if  the  task's  memory
       allocation policy is page interleaved.  Otherwise, this function returns an empty mask.

       numa_set_interleave_mask()  sets  the  memory  interleave  mask  for  the  current task to
       nodemask.  All new  memory  allocations  are  page  interleaved  over  all  nodes  in  the
       interleave  mask.  Interleaving  can  be  turned  off  again  by  passing  an  empty  mask
       (numa_no_nodes).  The page interleaving only occurs on the actual page fault that  puts  a
       new page into the current address space. It is also only a hint: the kernel will fall back
       to other nodes if no memory is available on the interleave target.

       numa_interleave_memory() interleaves size bytes of memory page by page from start on nodes
       specified  in  nodemask.  The size argument will be rounded up to a multiple of the system
       page size.  If nodemask contains nodes that are externally denied to  this  process,  this
       call  will  fail.   This  is  a  lower  level function to interleave allocated but not yet
       faulted in memory. Not yet faulted in means the  memory  is  allocated  using  mmap(2)  or
       shmat(2),  but  has  not  been  accessed  by  the  current process yet. The memory is page
       interleaved to all nodes specified in nodemask.  Normally numa_alloc_interleaved()  should
       be  used  for  private memory instead, but this function is useful to handle shared memory
       areas. To be useful the memory area should be several  megabytes  at  least  (or  tens  of
       megabytes  of hugetlbfs mappings) If the numa_set_strict() flag is true then the operation
       will cause a numa_error if there were already pages in the mapping that do not follow  the
       policy.

       numa_bind()  binds  the  current task and its children to the nodes specified in nodemask.
       They will only run on the CPUs of the specified nodes and only be able to allocate  memory
       from  them.   This  function  is  equivalent  to  calling  numa_run_on_node_mask(nodemask)
       followed by numa_set_membind(nodemask).  If tasks  should  be  bound  to  individual  CPUs
       inside nodes consider using numa_node_to_cpus and the sched_setaffinity(2) syscall.

       numa_set_localalloc()  sets  the  memory  allocation  policy for the calling task to local
       allocation.  In this mode, the preferred node for memory  allocation  is  effectively  the
       node where the task is executing at the time of a page allocation.

       numa_set_membind()  sets  the  memory allocation mask.  The task will only allocate memory
       from the nodes set in nodemask.  Passing an empty nodemask or  a  nodemask  that  contains
       nodes  other  than those in the mask returned by numa_get_mems_allowed() will result in an
       error.

       numa_get_membind() returns the mask of nodes from which memory can currently be allocated.
       If  the  returned  mask is equal to numa_all_nodes, then memory allocation is allowed from
       all nodes.

       numa_alloc_onnode() allocates memory on a  specific  node.   The  size  argument  will  be
       rounded  up  to  a  multiple of the system page size.  if the specified node is externally
       denied to this process, this call will fail.  This function is relatively slow compared to
       the malloc(3), family of functions.  The memory must be freed with numa_free().  On errors
       NULL is returned.

       numa_alloc_local() allocates size bytes of memory on the local node.   The  size  argument
       will  be  rounded  up  to a multiple of the system page size.  This function is relatively
       slow compared to the malloc(3) family  of  functions.   The  memory  must  be  freed  with
       numa_free().  On errors NULL is returned.

       numa_alloc_interleaved()  allocates  size  bytes  of memory page interleaved on all nodes.
       This function is relatively slow and should only be used for  large  areas  consisting  of
       multiple pages. The interleaving works at page level and will only show an effect when the
       area is large.  The allocated memory must be freed with numa_free().  On  error,  NULL  is
       returned.

       numa_alloc_interleaved_subset() attempts to allocate size bytes of memory page interleaved
       on all nodes.  The size argument will be rounded up to a multiple of the system page size.
       The  nodes on which a process is allowed to allocate memory may be constrained externally.
       If this is the case, this function may fail.  This function is relatively slow compare  to
       malloc(3),  family  of  functions  and  should  only be used for large areas consisting of
       multiple pages.  The interleaving works at page level and will only show  an  effect  when
       the  area  is large.  The allocated memory must be freed with numa_free().  On error, NULL
       is returned.

       numa_alloc() allocates size bytes of memory  with  the  current  NUMA  policy.   The  size
       argument  will  be  rounded  up  to  a multiple of the system page size.  This function is
       relatively slow compare to the malloc(3) family of functions.  The memory  must  be  freed
       with numa_free().  On errors NULL is returned.

       numa_realloc() changes the size of the memory area pointed to by old_addr from old_size to
       new_size.  The memory area pointed to by old_addr must have been allocated with one of the
       numa_alloc*  functions.   The new_size will be rounded up to a multiple of the system page
       size. The contents of the memory area will be unchanged to the minimum of the old and  new
       sizes; newly allocated memory will be uninitialized. The memory policy (and node bindings)
       associated with the original memory area will  be  preserved  in  the  resized  area.  For
       example,  if  the  initial area was allocated with a call to numa_alloc_onnode(), then the
       new pages (if the area is enlarged) will be allocated on the same node.   However,  if  no
       memory policy was set for the original area, then numa_realloc() cannot guarantee that the
       new pages will be allocated on the same node. On success, the address of the resized  area
       is  returned  (which  might be different from that of the initial area), otherwise NULL is
       returned and errno is set to indicate the error. The pointer returned by numa_realloc() is
       suitable for passing to numa_free().

       numa_free()  frees  size  bytes of memory starting at start, allocated by the numa_alloc_*
       functions above.  The size argument will be rounded up to a multiple of  the  system  page
       size.

       numa_run_on_node()  runs  the  current task and its children on a specific node. They will
       not migrate to CPUs of other nodes until the node affinity is reset with  a  new  call  to
       numa_run_on_node_mask().   Passing  -1  permits the kernel to schedule on all nodes again.
       On success, 0 is returned; on error -1 is returned, and  errno  is  set  to  indicate  the
       error.

       numa_run_on_node_mask()  runs the current task and its children only on nodes specified in
       nodemask.  They will not migrate to CPUs of other nodes until the node affinity  is  reset
       with  a new call to numa_run_on_node_mask() or numa_run_on_node().  Passing numa_all_nodes
       permits the kernel to schedule on all nodes again.  On success, 0 is returned; on error -1
       is returned, and errno is set to indicate the error.

       numa_get_run_node_mask()  returns  a  mask of CPUs on which the current task is allowed to
       run.

       numa_tonode_memory() put  memory  on  a  specific  node.  The  constraints  described  for
       numa_interleave_memory() apply here too.

       numa_tonodemask_memory()  put memory on a specific set of nodes. The constraints described
       for numa_interleave_memory() apply here too.

       numa_setlocal_memory() locates memory on the current node. The constraints  described  for
       numa_interleave_memory() apply here too.

       numa_police_memory()  locates  memory  with  the  current  NUMA  policy.  The  constraints
       described for numa_interleave_memory() apply here too.

       numa_distance() reports the distance in the  machine  topology  between  two  nodes.   The
       factors  are a multiple of 10. It returns 0 when the distance cannot be determined. A node
       has distance 10 to itself.  Reporting the distance requires  a  Linux  kernel  version  of
       2.6.10 or newer.

       numa_set_bind_policy()  specifies whether calls that bind memory to a specific node should
       use the preferred policy or a strict policy.  The preferred policy allows  the  kernel  to
       allocate  memory  on  other  nodes when there isn't enough free on the target node. strict
       will fail the allocation in that case.   Setting  the  argument  to  specifies  strict,  0
       preferred.  Note that specifying more than one node non strict may only use the first node
       in some kernel versions.

       numa_set_strict() sets a flag that says whether the functions allocating on specific nodes
       should use use a strict policy. Strict means the allocation will fail if the memory cannot
       be allocated on the target node.  Default operation is to fall back to other nodes.   This
       doesn't apply to interleave and default.

       numa_get_interleave_node()  is  used  by libnuma internally. It is probably not useful for
       user applications.  It uses the MPOL_F_NODE flag of the get_mempolicy system  call,  which
       is  not intended for application use (its operation may change or be removed altogether in
       future kernel versions). See get_mempolicy(2).

       numa_pagesize() returns the number of bytes in  page.  This  function  is  simply  a  fast
       alternative to repeated calls to the getpagesize system call.  See getpagesize(2).

       numa_sched_getaffinity()  retrieves  a  bitmask  of the cpus on which a task may run.  The
       task is specified by pid.  Returns the return value of the sched_getaffinity system  call.
       See  sched_getaffinity(2).  The bitmask must be at least the size of the kernel's cpu mask
       structure. Use numa_allocate_cpumask() to allocate it.  Test  the  bits  in  the  mask  by
       calling numa_bitmask_isbitset().

       numa_sched_setaffinity()  sets  a  task's  allowed cpu's to those cpu's specified in mask.
       The task is specified by pid.  Returns the return value of  the  sched_setaffinity  system
       call.     See    sched_setaffinity(2).     You    may    allocate    the    bitmask   with
       numa_allocate_cpumask().  Or the bitmask  may  be  smaller  than  the  kernel's  cpu  mask
       structure.  For  example,  call  numa_bitmask_alloc()  using a maximum number of cpus from
       numa_num_configured_cpus().  Set the bits in the mask by calling numa_bitmask_setbit().

       numa_node_to_cpus() converts a node number to a bitmask of CPUs.  The  user  must  pass  a
       bitmask  structure  with  a  mask buffer long enough to represent all possible cpu's.  Use
       numa_allocate_cpumask() to create it.  If the bitmask is not long enough errno will be set
       to ERANGE and -1 returned. On success 0 is returned.

       numa_node_of_cpu() returns the node that a cpu belongs to. If the user supplies an invalid
       cpu errno will be set to EINVAL and -1 will be returned.

       numa_allocate_cpumask () returns a bitmask of a  size  equal  to  the  kernel's  cpu  mask
       (kernel  type  cpumask_t).   In other words, large enough to represent NR_CPUS cpus.  This
       number of cpus can be gotten by calling numa_num_possible_cpus().  The  bitmask  is  zero-
       filled.

       numa_free_cpumask frees a cpumask previously allocate by numa_allocate_cpumask.

       numa_allocate_nodemask()  returns  a  bitmask  of  a  size equal to the kernel's node mask
       (kernel type nodemask_t).  In other words, large enough to represent  MAX_NUMNODES  nodes.
       This  number  of nodes can be gotten by calling numa_num_possible_nodes().  The bitmask is
       zero-filled.

       numa_free_nodemask() frees a nodemask previous allocated by numa_allocate_nodemask().

       numa_bitmask_alloc() allocates a bitmask structure  and  its  associated  bit  mask.   The
       memory  allocated for the bit mask contains enough words (type unsigned long) to contain n
       bits.  The bit mask is zero-filled.  The bitmask structure points  to  the  bit  mask  and
       contains the n value.

       numa_bitmask_clearall()  sets all bits in the bit mask to 0.  The bitmask structure points
       to the bit mask and contains its size ( bmp ->size).  The value of bmp is always returned.
       Note that numa_bitmask_alloc() creates a zero-filled bit mask.

       numa_bitmask_clearbit() sets a specified bit in a bit mask to 0.  Nothing is done if the n
       value is greater than the size of the bitmask (and no error is returned). The value of bmp
       is always returned.

       numa_bitmask_equal()  returns  1  if two bitmasks are equal.  It returns 0 if they are not
       equal.  If the bitmask structures control bit masks  of  different  sizes,  the  "missing"
       trailing bits of the smaller bit mask are considered to be 0.

       numa_bitmask_free() deallocates the memory of both the bitmask structure pointed to by bmp
       and the bit mask.  It is an error to attempt to free this bitmask twice.

       numa_bitmask_isbitset() returns the value of a specified bit in a  bit  mask.   If  the  n
       value is greater than the size of the bit map, 0 is returned.

       numa_bitmask_nbytes()  returns the size (in bytes) of the bit mask controlled by bmp.  The
       bit masks are always full words (type unsigned long), and the returned size is the  actual
       size of all those words.

       numa_bitmask_setall() sets all bits in the bit mask to 1.  The bitmask structure points to
       the bit mask and contains its size ( bmp ->size).  The value of bmp is always returned.

       numa_bitmask_setbit() sets a specified bit in a bit mask to 1.  Nothing is done  if  n  is
       greater  than  the  size  of  the  bitmask (and no error is returned). The value of bmp is
       always returned.

       copy_bitmask_to_nodemask() copies the body (the bit map itself) of the  bitmask  structure
       pointed  to  by bmp to the nodemask_t structure pointed to by the nodemask pointer. If the
       two areas differ in size, the copy is truncated to the size  of  the  receiving  field  or
       zero-filled.

       copy_nodemask_to_bitmask()  copies  the  nodemask_t  structure  pointed to by the nodemask
       pointer to the body (the bit map itself) of the bitmask structure pointed to  by  the  bmp
       pointer.  If  the  two  areas  differ  in  size,  the copy is truncated to the size of the
       receiving field or zero-filled.

       copy_bitmask_to_bitmask() copies the body (the bit map itself) of  the  bitmask  structure
       pointed  to  by the bmpfrom pointer to the body of the bitmask structure pointed to by the
       bmpto pointer. If the two areas differ in size, the copy is truncated to the size  of  the
       receiving field or zero-filled.

       numa_bitmask_weight()  returns a count of the bits that are set in the body of the bitmask
       pointed to by the bmp argument.

       numa_move_pages() moves a list of pages in the address space of the currently executing or
       current process.  It simply uses the move_pages system call.
       pid - ID of task.  If not valid, use the current task.
       count - Number of pages.
       pages - List of pages to move.
       nodes - List of nodes to which pages can be moved.
       status - Field to which status is to be returned.
       flags - MPOL_MF_MOVE or MPOL_MF_MOVE_ALL
       See move_pages(2).

       numa_migrate_pages()  simply  uses the migrate_pages system call to cause the pages of the
       calling task, or a specified task, to be migated from one set of nodes  to  another.   See
       migrate_pages(2).   The  bit  masks  representing  the  nodes  should  be  allocated  with
       numa_allocate_nodemask() , or with numa_bitmask_alloc() using an  n  value  returned  from
       numa_num_possible_nodes().    A   task's  current  node  set  can  be  gotten  by  calling
       numa_get_membind().    Bits   in   the   tonodes   mask   can   be   set   by   calls   to
       numa_bitmask_setbit().

       numa_error()  is  a  libnuma internal function that can be overridden by the user program.
       This function is called with a char * argument when a libnuma function fails.   Overriding
       the  library  internal  definition makes it possible to specify a different error handling
       strategy when a  libnuma  function  fails.  It  does  not  affect  numa_available().   The
       numa_error()  function  defined  in  libnuma  prints an error on stderr and terminates the
       program if  numa_exit_on_error  is  set  to  a  non-zero  value.   The  default  value  of
       numa_exit_on_error is zero.

       numa_warn()  is  a  libnuma  internal  function  that  can  be also overridden by the user
       program.  It is called to warn the user when a libnuma  function  encounters  a  non-fatal
       error.   The  default  implementation prints a warning to stderr.  The first argument is a
       unique number identifying each warning. After  that  there  is  a  printf(3)-style  format
       string   and   a   variable  number  of  arguments.   numa_warn  exits  the  program  when
       numa_exit_on_warn is set to a non-zero value.  The default value of  numa_exit_on_warn  is
       zero.

Compatibility with libnuma version 1

       Binaries  that  were  compiled  for  libnuma version 1 need not be re-compiled to run with
       libnuma version 2.
       Source codes written for libnuma version 1 may be re-compiled without change with  version
       2   installed.   To   do   so,   in  the  code's  Makefile  add  this  option  to  CFLAGS:
       -DNUMA_VERSION1_COMPATIBILITY

THREAD SAFETY

       numa_set_bind_policy and numa_exit_on_error are process global. The other calls are thread
       safe.

COPYRIGHT

       Copyright  2002,  2004, 2007, 2008 Andi Kleen, SuSE Labs.  libnuma is under the GNU Lesser
       General Public License, v2.1.

SEE ALSO

       get_mempolicy(2),   set_mempolicy(2),   getpagesize(2),   mbind(2),   mmap(2),   shmat(2),
       numactl(8), sched_getaffinity(2) sched_setaffinity(2) move_pages(2) migrate_pages(2)