Linux man pages : munlockall (2)
MUNLOCKALL(2) Linux Programmer's Manual MUNLOCKALL(2)
munlockall - reenable paging for calling process
munlockall reenables paging for all pages mapped into the address space
of the calling process.
Memory locks do not stack, i.e., pages which have been locked several
times by calls to mlock or mlockall will be unlocked by a single call
to munlockall. Pages which are mapped to several locations or by sev-
eral processes stay locked into RAM as long as they are locked at least
at one location or by at least one process.
On POSIX systems on which mlockall and munlockall are available,
_POSIX_MEMLOCK is defined in <unistd.h> .
On success, munlockall returns zero. On error, -1 is returned and
errno is set appropriately.
mlockall(2), mlock(2), munlock(2)
Linux 1.3.43 1995-11-26 MUNLOCKALL(2)