plucky (3) pmem2_get_drain_fn.3.gz

Provided by: libpmem2-dev_1.13.1-1.1ubuntu2_amd64 bug

NAME
       pmem2_get_drain_fn() - get a drain function


SYNOPSIS
              #include <libpmem2.h>

              typedef void (*pmem2_drain_fn)(void);

              struct pmem2_map;

              pmem2_drain_fn pmem2_get_drain_fn(struct pmem2_map *map);


DESCRIPTION
       The  pmem2_get_drain_fn()  function  returns a pointer to a function responsible for efficiently draining
       flushes (see pmem2_get_flush_fn(3)) in the range owned by map.  Draining, in this context,  means  making
       sure  that the flushes before this operation won’t be reordered after it.  While it is not strictly true,
       draining can be thought of as waiting for previous flushes to complete.

       If two (or more) mappings share the same drain function, it is safe to call this function  once  for  all
       flushes belonging to those mappings.


RETURN VALUE
       The pmem2_get_drain_fn() function never returns NULL.

       The pmem2_get_drain_fn() for the same map always returns the same function.  This means that it’s safe to
       cache its return value.  However, this function is very cheap (because it returns a  precomputed  value),
       so caching may not be necessary.


SEE ALSO
       pmem2_get_flush_fn(3), pmem2_get_persist_fn(3), pmem2_map_new(3), libpmem2(7) and <https://pmem.io>