motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-07 17:53:56 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

coroutine: add flag to re-queue at front of CoQueue

Browse source 
When a coroutine wakes up it may determine that it must re-queue.
Normally coroutines are pushed onto the back of the CoQueue, but for
fairness it may be necessary to push it onto the front of the CoQueue.

Add a flag to specify that the coroutine should be pushed onto the front
of the CoQueue. A later patch will use this to ensure fairness in the
bounce buffer CoQueue used by the blkio BlockDriver.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20221013185908.1297568-2-stefanha@redhat.com
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This commit is contained in:
Stefan Hajnoczi 2022-10-13 14:58:56 -04:00
parent 79fc2fb685
commit 0421b563ab
2 changed files with 20 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

9
util/qemu-coroutine-lock.c
View file

@ -39,10 +39,15 @@ void qemu_co_queue_init(CoQueue *queue)
QSIMPLEQ_INIT(&queue->entries);
}
void coroutine_fn qemu_co_queue_wait_impl(CoQueue *queue, QemuLockable *lock)
void coroutine_fn qemu_co_queue_wait_impl(CoQueue *queue, QemuLockable *lock,
CoQueueWaitFlags flags)
{
Coroutine *self = qemu_coroutine_self();
QSIMPLEQ_INSERT_TAIL(&queue->entries, self, co_queue_next);
if (flags & CO_QUEUE_WAIT_FRONT) {
QSIMPLEQ_INSERT_HEAD(&queue->entries, self, co_queue_next);
} else {
QSIMPLEQ_INSERT_TAIL(&queue->entries, self, co_queue_next);
}
if (lock) {
qemu_lockable_unlock(lock);