On Fri, Mar 28, 2025 at 06:02:46PM +0800, Cindy Lu wrote:
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
nit: s/change/changed
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 <l...@redhat.com>
---
drivers/vhost/vhost.c | 38 ++++++++++++++++++++++++++++++++++++++
1 file changed, 38 insertions(+)
I tried to build commit by commit (mainly to check bisection), and I
discovered that nowdays unused functions produce an error (yes, we can
mute it for example by setting CONFIG_WERROR to N), but I wanted to
point it out:
../drivers/vhost/vhost.c:391:12: error: ‘vhost_run_work_kthread_list’ defined
but not used [-Werror=unused-function]
391 | static int vhost_run_work_kthread_list(void *data)
So not sure if we need to squash this where we use it.
Same issue also for the next 2 patches.
Thanks,
Stefano
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 250dc43f1786..9500e85b42ce 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
