4 commits

Author	SHA1	Message	Date
Andreas Kling	f4978b2be1	Kernel: Use IntrusiveList to make WaitQueue allocation-free :^)	2019-12-22 12:38:01 +01:00
Andreas Kling	a0e38922bd	Kernel: Break out of the idle loop on WaitQueue wake instead of on IRQ ... Now that we have proper wait queues to drive waiter wakeup, we can use the wake actions to break out of the scheduler's idle loop when we've got a thread to run.	2019-12-08 00:33:35 +01:00
Andreas Kling	5859e16e53	Kernel: Use a dedicated thread state for wait-queued threads ... Instead of using the generic block mechanism, wait-queued threads now go into the special Queued state. This fixes an issue where signal dispatch would unblock a wait-queued thread (because signal dispatch unblocks blocked threads) and cause confusion since the thread only expected to be awoken by the queue.	2019-12-01 16:02:58 +01:00
Andreas Kling	f067730f6b	Kernel: Add a WaitQueue for Thread queueing/waking and use it for Lock ... The kernel's Lock class now uses a proper wait queue internally instead of just having everyone wake up regularly to try to acquire the lock. We also keep the donation mechanism, so that whenever someone tries to take the lock and fails, that thread donates the remainder of its timeslice to the current lock holder. After unlocking a Lock, the unlocking thread calls WaitQueue::wake_one, which unblocks the next thread in queue.	2019-12-01 12:07:43 +01:00