Re: [RFC 2/7] vhost: Add kthread support in function vhost_worker_queue()
From: Jason Wang <jasowang@redhat.com>
Date: 2024-08-27 02:36:31
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On Mon, Aug 19, 2024 at 5:29 PM Cindy Lu [off-list ref] wrote:
Added back the previously removed function vhost_worker_queue() and renamed it to vhost_worker_queue_khtread(). The new vhost_worker_queue() will select the different mode based on the value of the parameter. Signed-off-by: Cindy Lu <redacted>
It looks like a partial revert of some previous commit, please mention the commit id in the change log as least. So did for the following 3 or 4 patches. Thanks
quoted hunk ↗ jump to hunk
--- drivers/vhost/vhost.c | 30 ++++++++++++++++++++++++++++-- drivers/vhost/vhost.h | 1 + 2 files changed, 29 insertions(+), 2 deletions(-)diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c index da701f6b3f2c..6261c9df468e 100644 --- a/drivers/vhost/vhost.c +++ b/drivers/vhost/vhost.c@@ -236,8 +236,8 @@ void vhost_poll_stop(struct vhost_poll *poll) } EXPORT_SYMBOL_GPL(vhost_poll_stop); -static void vhost_worker_queue(struct vhost_worker *worker, - struct vhost_work *work) +static void vhost_worker_queue_task(struct vhost_worker *worker, + struct vhost_work *work) { if (!test_and_set_bit(VHOST_WORK_QUEUED, &work->flags)) { /* We can only add the work to the list after we're@@ -249,6 +249,32 @@ static void vhost_worker_queue(struct vhost_worker *worker, } } +static void vhost_work_queue_kthread(struct vhost_worker *worker, + struct vhost_work *work) +{ + if (!worker) + return; + + if (!test_and_set_bit(VHOST_WORK_QUEUED, &work->flags)) { + /* We can only add the work to the list after we're + * sure it was not in the list. + * test_and_set_bit() implies a memory barrier. + */ + llist_add(&work->node, &worker->work_list); + + wake_up_process(worker->task); + } +} + +static void vhost_worker_queue(struct vhost_worker *worker, + struct vhost_work *work) +{ + if (use_kthread) { + vhost_work_queue_kthread(worker, work); + } else { + vhost_worker_queue_task(worker, work); + } +} bool vhost_vq_work_queue(struct vhost_virtqueue *vq, struct vhost_work *work) { struct vhost_worker *worker;diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h index bb75a292d50c..c7f126fd09e8 100644 --- a/drivers/vhost/vhost.h +++ b/drivers/vhost/vhost.h@@ -27,6 +27,7 @@ struct vhost_work { }; struct vhost_worker { + struct task_struct *task; struct vhost_task *vtsk; struct vhost_dev *dev; /* Used to serialize device wide flushing with worker swapping. */ --2.45.0