FreeBSD manual
download PDF document: vm_map_lock_downgrade.9.pdf
VM_MAP_LOCK(9) FreeBSD Kernel Developer's Manual VM_MAP_LOCK(9)
NAME
vm_map_lock, vm_map_unlock, vm_map_lock_read, vm_map_unlock_read,
vm_map_trylock, vm_map_trylock_read, vm_map_lock_upgrade,
vm_map_lock_downgrade - vm_map locking macros
SYNOPSIS
#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_map.h>
void
vm_map_lock(vm_map_t map);
void
vm_map_unlock(vm_map_t map);
void
vm_map_lock_read(vm_map_t map);
void
vm_map_unlock_read(vm_map_t map);
int
vm_map_trylock(vm_map_t map);
int
vm_map_trylock_read(vm_map_t map);
int
vm_map_lock_upgrade(vm_map_t map);
int
vm_map_lock_downgrade(vm_map_t map);
DESCRIPTION
The vm_map_lock() macro obtains an exclusive lock on map.
The vm_map_unlock() macro releases an exclusive lock on map.
The vm_map_lock_read() macro obtains a read-lock on map.
The vm_map_unlock_read() macro releases a read-lock on map.
The vm_map_trylock() macro attempts to obtain an exclusive lock on map.
It returns FALSE if the lock cannot be immediately acquired; otherwise
return TRUE with the lock acquired.
The vm_map_trylock_read() macro attempts to obtain a read-lock on map.
It returns FALSE if the lock cannot be immediately acquired; otherwise
return TRUE with the lock acquired.
The vm_map_lock_upgrade() macro attempts to atomically upgrade a read-
lock on map to an exclusive lock.
The vm_map_lock_downgrade() macro attempts to downgrade an exclusive lock
on map to a read-lock.
AUTHORS
This manual page was written by Bruce M Simpson <bms@spc.org>.
FreeBSD 14.0-RELEASE-p6 July 19, 2003 FreeBSD 14.0-RELEASE-p6