* remove_user_mutex_entry(): The next entry wasn't removed from its own list.
* user_mutex_unlock_locked(): Set or clear the locked flag depending on whether
we wake up a waiter.
* _user_mutex_switch_lock(): The syscall cannot be restartable.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36319 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Moved created subdirectory src/system/kernel/lock.cpp to new subdirectory
locks.
* Added syscalls for a new kind of mutex. A mutex consists only of an int32 and
doesn't require any kernel resources. So it's initialization cannot fail
(it consists only of setting the mutex value to 0). An uncontended lock or
unlock operation can basically consist of an atomic_*() in userland. The
syscalls (when the mutex is contended) are a bit more expensive than semaphore
operations, though.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36158 a95241bf-73f2-0310-859d-f6bbb57e9c96

* remove_user_mutex_entry(): The next entry wasn't removed from its own list.
* user_mutex_unlock_locked(): Set or clear the locked flag depending on whether
we wake up a waiter.
* _user_mutex_switch_lock(): The syscall cannot be restartable.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36319 a95241bf-73f2-0310-859d-f6bbb57e9c96

* Moved created subdirectory src/system/kernel/lock.cpp to new subdirectory
locks.
* Added syscalls for a new kind of mutex. A mutex consists only of an int32 and
doesn't require any kernel resources. So it's initialization cannot fail
(it consists only of setting the mutex value to 0). An uncontended lock or
unlock operation can basically consist of an atomic_*() in userland. The
syscalls (when the mutex is contended) are a bit more expensive than semaphore
operations, though.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36158 a95241bf-73f2-0310-859d-f6bbb57e9c96