VM_MAP_LOCK(9) MidnightBSD 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. Currently this is implemented as an exclusive lock.

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. Currently this is implemented as an exclusive lock.

The vm_map_lock_upgrade() macro attempts to atomically upgrade a read-lock on map to an exclusive lock. As read-locks are currently implemented as exclusive locks, this macro is a no-op.

The vm_map_lock_downgrade() macro attempts to downgrade an exclusive lock on map to a read-lock. As read-locks are currently implemented as exclusive locks, this macro is a no-op.

IMPLEMENTATION NOTES

Currently, all of the locking macros implement their locks as sleep locks.

SEE ALSO

vm_map(9)

AUTHORS

This manual page was written by Bruce M Simpson 〈bms@spc.org〉.

MidnightBSD 0.3 July 19, 2003 MidnightBSD 0.3