focal (3) memkind_default.3.gz

NAME

       memkind_default - default implementations for memkind operations.
       Note:  This  is  EXPERIMENTAL API. The functionality and the header file itself can be changed (including
       non-backward compatible changes), or removed.

SYNOPSIS

       int memkind_default_create(struct memkind *kind, struct memkind_ops *ops, const char *name);
       int memkind_default_destroy(struct memkind *kind);
       void *memkind_default_malloc(struct memkind *kind, size_t size);
       void *memkind_default_calloc(struct memkind *kind, size_t num, size_t size);
       int memkind_default_posix_memalign(struct memkind *kind, void **memptr, size_t alignment, size_t size);
       void *memkind_default_realloc(struct memkind *kind, void *ptr, size_t size);
       void memkind_default_free(struct memkind *kind, void *ptr);
       void *memkind_default_mmap(struct memkind *kind, void *addr, size_t size);
       int memkind_default_mbind(struct memkind *kind, void *ptr, size_t len);
       int memkind_default_get_mmap_flags(struct memkind *kind, int *flags);
       int memkind_default_get_mbind_mode(struct memkind *kind, int *mode);
       size_t memkind_default_malloc_usable_size(struct memkind *kind, void *ptr);
       int memkind_preferred_get_mbind_mode(struct memkind *kind, int *mode);
       int memkind_interleave_get_mbind_mode(struct memkind *kind, int *mode);
       int memkind_nohugepage_madvise(struct memkind *kind, void *addr, size_t size);
       int memkind_posix_check_alignment(struct memkind *kind, size_t alignment);
       int memkind_default_get_mbind_nodemask(struct memkind  *kind,  unsigned  long  *nodemask,  unsigned  long
       maxnode);
       void memkind_default_init_once(void);
       bool size_out_of_bounds(size_t size);

DESCRIPTION

       Default  implementations  for memkind operations which include a several useful methods that are not part
       of the MEMKIND_DEFAULT kind which is a fall through to the jemalloc implementation.

       memkind_default_create() implements the required start up for every kind. If a kind  does  not  point  to
       this  function  directly  for  its  ops.create() operation, then the function that it points to must call
       memkind_default_create() at its start.

       memkind_default_destroy() implements the required shutdown for every kind. If a kind does  not  point  to
       this  function  directly  for  its ops.destroy() operation, then the function that it points to must call
       memkind_default_destroy() at its end.

       memkind_default_malloc() is a direct call through the jemalloc's malloc().

       memkind_default_calloc() is a direct call through the jemalloc's calloc().

       memkind_default_posix_memalign() is a direct call through the jemalloc's posix_memalign().

       memkind_default_realloc() is a direct call through the jemalloc's realloc().

       memkind_default_free() is a direct call through the jemalloc's free().  Note  that  this  method  can  be
       called  on any pointer returned by a jemalloc allocation, and in particular, all of the arena allocations
       described in memkind_arena(3) can use this function for freeing.

       memkind_default_mmap() This calls the ops->get_mmap_flags() operations for the kind, or falls back on the
       default  implementations if the function pointers are NULL.  The results of these calls are passed to the
       mmap(2) call to allocate pages from the operating system.  The addr is the hint passed through to mmap(2)
       and  size  is  the  size  of  the  buffer  to  be allocated.  The return value is the allocated buffer or
       MAP_FAILED in the case of an error.

       memkind_default_mbind()  makes  calls  the  kind's  ops.get_mbind_nodemask()   and   ops.get_mbind_mode()
       operations to gather inputs and then calls the mbind(2) system call using the results along with and user
       input ptr and len.

       memkind_default_get_mmap_flags() sets flags  to  MAP_PRIVATE  |  MAP_ANONYMOUS.   See  mmap(2)  for  more
       information about these flags.

       memkind_default_get_mbind_mode()  sets  mode  to MPOL_BIND.  See mbind(2) for more information about this
       flag.

       memkind_default_malloc_usable_size() is a direct call through the jemalloc's malloc_usable_size().

       memkind_preferred_get_mbind_mode() sets mode to MPOL_PREFERRED.  See mbind(2) for more information  about
       this flag.

       memkind_interleave_get_mbind_mode()  sets  mode  to  MPOL_INTERLEAVE.   See mbind(2) for more information
       about this flag.

       memkind_nohugepage_madvise() calls madvise(2) with the MADV_NOHUGEPAGE advice.  See madvise(2)  for  more
       information about this option.

       memkind_posix_check_alignment()  can be used to check the alignment value for memkind_posix_memalign() to
       ensure that is abides by the POSIX requirements: alignment must be a power of 2  at  least  as  large  as
       sizeof(void*).

       memkind_default_get_mbind_nodemask() wraps jemalloc's copy_bitmask_to_bitmask.  This function copies body
       of the bitmask structure into passed pointer.

       memkind_default_init_once() initializes heap manager.

       size_out_of_bounds() returns true if given size is out of bounds, otherwise will return false.

COPYRIGHT

       Copyright (C) 2014 - 2019 Intel Corporation. All rights reserved.

SEE ALSO

       memkind(3), memkind_arena(3), memkind_hbw(3), memkind_hugetlb(3), memkind_pmem(3), jemalloc(3), mbind(2),
       mmap(2)