2 .\" Copyright (c) 2003 Bruce M Simpson <bms@spc.org>
3 .\" All rights reserved.
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34 .Nm vm_map_lock_read ,
35 .Nm vm_map_unlock_read ,
37 .Nm vm_map_trylock_read ,
38 .Nm vm_map_lock_upgrade ,
39 .Nm vm_map_lock_downgrade
40 .Nd vm_map locking macros
46 .Fn vm_map_lock "vm_map_t map"
48 .Fn vm_map_unlock "vm_map_t map"
50 .Fn vm_map_lock_read "vm_map_t map"
52 .Fn vm_map_unlock_read "vm_map_t map"
54 .Fn vm_map_trylock "vm_map_t map"
56 .Fn vm_map_trylock_read "vm_map_t map"
58 .Fn vm_map_lock_upgrade "vm_map_t map"
60 .Fn vm_map_lock_downgrade "vm_map_t map"
64 macro obtains an exclusive lock on
69 macro releases an exclusive lock on
74 macro obtains a read-lock on
78 .Fn vm_map_unlock_read
79 macro releases a read-lock on
84 macro attempts to obtain an exclusive lock on
86 It returns FALSE if the lock cannot be immediately acquired;
87 otherwise return TRUE with the lock acquired.
90 .Fn vm_map_trylock_read
91 macro attempts to obtain a read-lock on
93 It returns FALSE if the lock cannot be immediately acquired;
94 otherwise return TRUE with the lock acquired.
97 .Fn vm_map_lock_upgrade
98 macro attempts to atomically upgrade a read-lock on
100 to an exclusive lock.
103 .Fn vm_map_lock_downgrade
104 macro attempts to downgrade an exclusive lock on
107 .Sh IMPLEMENTATION NOTES
108 Currently, all of the locking macros implement their locks as sleep locks.
112 This manual page was written by
113 .An Bruce M Simpson Aq bms@spc.org .