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 - 2020 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)