On Thu, Mar 02, 2023 at 04:30:04PM +0100, Simon Horman wrote:
On Thu, Mar 02, 2023 at 12:34:19PM +0100, Stefano Garzarella wrote:
Let's use our own kthread to run device jobs.
This allows us more flexibility, especially we can attach the kthread
to the user address space when vDPA uses user's VA.
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim.h | 3 ++-
drivers/vdpa/vdpa_sim/vdpa_sim.c | 17 ++++++++++++-----
2 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
index acee20faaf6a..ce83f9130a5d 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -57,7 +57,8 @@ struct vdpasim_dev_attr {
struct vdpasim {
struct vdpa_device vdpa;
struct vdpasim_virtqueue *vqs;
- struct work_struct work;
+ struct kthread_worker *worker;
+ struct kthread_work work;
struct vdpasim_dev_attr dev_attr;
/* spinlock to synchronize virtqueue state */
spinlock_t lock;
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index a6ee830efc38..6feb29726c2a 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -11,8 +11,8 @@
#include <linux/module.h>
#include <linux/device.h>
#include <linux/kernel.h>
+#include <linux/kthread.h>
#include <linux/slab.h>
-#include <linux/sched.h>
#include <linux/dma-map-ops.h>
#include <linux/vringh.h>
#include <linux/vdpa.h>
@@ -116,7 +116,7 @@ static void vdpasim_do_reset(struct vdpasim *vdpasim)
static const struct vdpa_config_ops vdpasim_config_ops;
static const struct vdpa_config_ops vdpasim_batch_config_ops;
-static void vdpasim_work_fn(struct work_struct *work)
+static void vdpasim_work_fn(struct kthread_work *work)
{
struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
@@ -159,7 +159,13 @@ struct vdpasim *vdpasim_create(struct vdpasim_dev_attr *dev_attr,
vdpasim = vdpa_to_sim(vdpa);
vdpasim->dev_attr = *dev_attr;
- INIT_WORK(&vdpasim->work, vdpasim_work_fn);
+
+ kthread_init_work(&vdpasim->work, vdpasim_work_fn);
+ vdpasim->worker = kthread_create_worker(0, "vDPA sim worker: %s",
+ dev_attr->name);
+ if (IS_ERR(vdpasim->worker))
+ goto err_iommu;
Branching to err_iommu will result in a call to put_device(dev)...
Good catch!
+
spin_lock_init(&vdpasim->lock);
spin_lock_init(&vdpasim->iommu_lock);
... but dev is not initialised until the line following this hunk,
which is:
dev = &vdpasim->vdpa.dev;
In order to avoid leaking dev I _think_ the correct approach
is to move the initialisation of dev above the branch to
err_iommu, perhaps above the call to kthread_init_work()
is a good place.
Yep, I agree. I'll fix in v3.
Thanks,
Stefano
This does move the assignment outside the locks above.
But I _think_ that is ok.
@@ -212,7 +218,7 @@ EXPORT_SYMBOL_GPL(vdpasim_create);
void vdpasim_schedule_work(struct vdpasim *vdpasim)
{
- schedule_work(&vdpasim->work);
+ kthread_queue_work(vdpasim->worker, &vdpasim->work);
}
EXPORT_SYMBOL_GPL(vdpasim_schedule_work);
@@ -612,7 +618,8 @@ static void vdpasim_free(struct vdpa_device *vdpa)
struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
int i;
- cancel_work_sync(&vdpasim->work);
+ kthread_cancel_work_sync(&vdpasim->work);
+ kthread_destroy_worker(vdpasim->worker);
for (i = 0; i < vdpasim->dev_attr.nvqs; i++) {
vringh_kiov_cleanup(&vdpasim->vqs[i].out_iov);
--
2.39.2
