diff options
Diffstat (limited to 'sys/vm/vm_map.c')
-rw-r--r-- | sys/vm/vm_map.c | 118 |
1 files changed, 60 insertions, 58 deletions
diff --git a/sys/vm/vm_map.c b/sys/vm/vm_map.c index b56b1c3..3e1b4ab 100644 --- a/sys/vm/vm_map.c +++ b/sys/vm/vm_map.c @@ -277,73 +277,61 @@ vm_map_entry_set_behavior(struct vm_map_entry *entry, u_char behavior) } void -vm_map_lock(vm_map_t map) +_vm_map_lock(vm_map_t map, const char *file, int line) { vm_map_printf("locking map LK_EXCLUSIVE: %p\n", map); - if (lockmgr(&map->lock, LK_EXCLUSIVE, NULL, curthread) != 0) - panic("vm_map_lock: failed to get lock"); + _sx_xlock(&map->lock, file, line); map->timestamp++; } +int +_vm_map_try_lock(vm_map_t map, const char *file, int line) +{ + vm_map_printf("trying to lock map LK_EXCLUSIVE: %p\n", map); + if (_sx_try_xlock(&map->lock, file, line)) { + map->timestamp++; + return (0); + } + return (EWOULDBLOCK); +} + void -vm_map_unlock(vm_map_t map) +_vm_map_unlock(vm_map_t map, const char *file, int line) { vm_map_printf("locking map LK_RELEASE: %p\n", map); - lockmgr(&(map)->lock, LK_RELEASE, NULL, curthread); + _sx_xunlock(&map->lock, file, line); } void -vm_map_lock_read(vm_map_t map) +_vm_map_lock_read(vm_map_t map, const char *file, int line) { vm_map_printf("locking map LK_SHARED: %p\n", map); - lockmgr(&(map)->lock, LK_SHARED, NULL, curthread); + _sx_slock(&map->lock, file, line); } void -vm_map_unlock_read(vm_map_t map) +_vm_map_unlock_read(vm_map_t map, const char *file, int line) { vm_map_printf("locking map LK_RELEASE: %p\n", map); - lockmgr(&(map)->lock, LK_RELEASE, NULL, curthread); -} - -static __inline__ int -_vm_map_lock_upgrade(vm_map_t map, struct thread *td) { - int error; - - vm_map_printf("locking map LK_EXCLUPGRADE: %p\n", map); - error = lockmgr(&map->lock, LK_EXCLUPGRADE, NULL, td); - if (error == 0) - map->timestamp++; - return error; + _sx_sunlock(&map->lock, file, line); } int -vm_map_lock_upgrade(vm_map_t map) +_vm_map_lock_upgrade(vm_map_t map, const char *file, int line) { - return (_vm_map_lock_upgrade(map, curthread)); + vm_map_printf("locking map LK_EXCLUPGRADE: %p\n", map); + if (_sx_try_upgrade(&map->lock, file, line)) { + map->timestamp++; + return (0); + } + return (EWOULDBLOCK); } void -vm_map_lock_downgrade(vm_map_t map) +_vm_map_lock_downgrade(vm_map_t map, const char *file, int line) { vm_map_printf("locking map LK_DOWNGRADE: %p\n", map); - lockmgr(&map->lock, LK_DOWNGRADE, NULL, curthread); -} - -void -vm_map_set_recursive(vm_map_t map) -{ - mtx_lock((map)->lock.lk_interlock); - map->lock.lk_flags |= LK_CANRECURSE; - mtx_unlock((map)->lock.lk_interlock); -} - -void -vm_map_clear_recursive(vm_map_t map) -{ - mtx_lock((map)->lock.lk_interlock); - map->lock.lk_flags &= ~LK_CANRECURSE; - mtx_unlock((map)->lock.lk_interlock); + _sx_downgrade(&map->lock, file, line); } vm_offset_t @@ -417,7 +405,7 @@ vm_map_init(vm_map_t map, vm_offset_t min, vm_offset_t max) map->first_free = &map->header; map->hint = &map->header; map->timestamp = 0; - lockinit(&map->lock, PVM, "thrd_sleep", 0, LK_NOPAUSE); + sx_init(&map->lock, "thrd_sleep"); } void @@ -425,7 +413,7 @@ vm_map_destroy(map) struct vm_map *map; { GIANT_REQUIRED; - lockdestroy(&map->lock); + sx_destroy(&map->lock); } /* @@ -1482,17 +1470,13 @@ vm_map_user_pageable( eend = entry->end; /* First we need to allow map modifications */ - vm_map_set_recursive(map); - vm_map_lock_downgrade(map); map->timestamp++; rv = vm_fault_user_wire(map, entry->start, entry->end); if (rv) { - + vm_map_lock(map); entry->wired_count--; entry->eflags &= ~MAP_ENTRY_USER_WIRED; - - vm_map_clear_recursive(map); vm_map_unlock(map); /* @@ -1506,8 +1490,14 @@ vm_map_user_pageable( return rv; } - vm_map_clear_recursive(map); - if (vm_map_lock_upgrade(map)) { + /* + * XXX- This is only okay because we have the + * Giant lock. If the VM system were to be + * reentrant, we'd know that we really can't + * do this. Still, this behavior is no worse + * than the old recursion... + */ + if (vm_map_try_lock(map)) { vm_map_lock(map); if (vm_map_lookup_entry(map, estart, &entry) == FALSE) { @@ -1745,13 +1735,13 @@ vm_map_pageable( entry = entry->next; } - if (vm_map_pmap(map) == kernel_pmap) { - vm_map_lock(map); - } if (rv) { - vm_map_unlock(map); + if (vm_map_pmap(map) != kernel_pmap) + vm_map_unlock_read(map); (void) vm_map_pageable(map, start, failed, TRUE); return (rv); + } else if (vm_map_pmap(map) == kernel_pmap) { + vm_map_lock(map); } /* * An exclusive lock on the map is needed in order to call @@ -1760,6 +1750,7 @@ vm_map_pageable( */ if (vm_map_pmap(map) != kernel_pmap && vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); vm_map_lock(map); if (vm_map_lookup_entry(map, start, &start_entry) == FALSE) { @@ -2531,8 +2522,10 @@ Retry: * might have intended by limiting the stack size. */ if (grow_amount > stack_entry->start - end) { - if (vm_map_lock_upgrade(map)) + if (vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); goto Retry; + } stack_entry->avail_ssize = stack_entry->start - end; @@ -2562,8 +2555,10 @@ Retry: ctob(vm->vm_ssize); } - if (vm_map_lock_upgrade(map)) + if (vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); goto Retry; + } /* Get the preliminary new entry start value */ addr = stack_entry->start - grow_amount; @@ -2782,8 +2777,10 @@ RetryLookup:; * -- one just moved from the map to the new * object. */ - if (vm_map_lock_upgrade(map)) + if (vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); goto RetryLookup; + } vm_object_shadow( &entry->object.vm_object, &entry->offset, @@ -2804,8 +2801,10 @@ RetryLookup:; */ if (entry->object.vm_object == NULL && !map->system_map) { - if (vm_map_lock_upgrade(map)) + if (vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); goto RetryLookup; + } entry->object.vm_object = vm_object_allocate(OBJT_DEFAULT, atop(entry->end - entry->start)); entry->offset = 0; @@ -3038,7 +3037,10 @@ vm_uiomove( pmap_remove (map->pmap, uaddr, tend); vm_object_pmap_copy_1 (srcobject, oindex, oindex + osize); - vm_map_lock_upgrade(map); + if (vm_map_lock_upgrade(map)) { + vm_map_unlock_read(map); + vm_map_lock(map); + } if (entry == &map->header) { map->first_free = &map->header; |