1 // core/thread.cc -- Scheduler and thread creation/destruction
3 // This software is copyright (c) 2006 Scott Wood <scott@buserror.net>.
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31 #include <util/lock.h>
32 #include <kern/thread.h>
35 // OPT: add inline, lockless uncontended case
37 // FIXME: Allow a high-priority blocker to steal a lock from
38 // a low-priority holder if the holder has not yet run. This
39 // prevents rescheduling every iteration if both threads are
40 // repeatedly acquiring and releasing the lock.
44 DroppableAutoSpinLockRecIRQ autolock(spinlock);
47 lockval = reinterpret_cast<ulong>(curthread);
51 assert(lockval != reinterpret_cast<ulong>(curthread));
53 Threads::ThreadBlocker blocker(curthread);
54 waitqueue.block(&blocker);
57 lockval = reinterpret_cast<ulong>(curthread);
58 waitqueue.unblock(&blocker);
63 curthread->block(&blocker);
65 // FIXME: interruptible locks
66 assert(lockval == reinterpret_cast<ulong>(curthread));
71 AutoSpinLockRecIRQ autolock(spinlock);
72 assert(lockval == reinterpret_cast<ulong>(curthread));
74 if (waitqueue.empty()) {
79 Threads::Blocker *b = waitqueue.unblock_one();
80 lockval = reinterpret_cast<ulong>(b->thread);