[PATCH v6 2/6] vhost: Reintroduce vhost_worker to support kthread
From: Cindy Lu <hidden>
Date: 2025-02-23 15:41:05
Also in:
lkml, virtualization
Subsystem:
the rest, virtio host (vhost) · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
Add the previously removed function vhost_worker() back
to support the kthread and rename it to vhost_run_work_kthread_list.
The old function vhost_worker was change to support task in
commit 6e890c5d5021 ("vhost: use vhost_tasks for worker threads")
change to xarray in
commit 1cdaafa1b8b4 ("vhost: replace single worker pointer with xarray")
Signed-off-by: Cindy Lu <redacted>
---
drivers/vhost/vhost.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index eaddbd39c29b..1feba29abf95 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c@@ -388,6 +388,44 @@ static void vhost_vq_reset(struct vhost_dev *dev, __vhost_vq_meta_reset(vq); } +static int vhost_run_work_kthread_list(void *data) +{ + struct vhost_worker *worker = data; + struct vhost_work *work, *work_next; + struct vhost_dev *dev = worker->dev; + struct llist_node *node; + + kthread_use_mm(dev->mm); + + for (;;) { + /* mb paired w/ kthread_stop */ + set_current_state(TASK_INTERRUPTIBLE); + + if (kthread_should_stop()) { + __set_current_state(TASK_RUNNING); + break; + } + node = llist_del_all(&worker->work_list); + if (!node) + schedule(); + + node = llist_reverse_order(node); + /* make sure flag is seen after deletion */ + smp_wmb(); + llist_for_each_entry_safe(work, work_next, node, node) { + clear_bit(VHOST_WORK_QUEUED, &work->flags); + __set_current_state(TASK_RUNNING); + kcov_remote_start_common(worker->kcov_handle); + work->fn(work); + kcov_remote_stop(); + cond_resched(); + } + } + kthread_unuse_mm(dev->mm); + + return 0; +} + static bool vhost_run_work_list(void *data) { struct vhost_worker *worker = data;
--
2.45.0