Limit the number of requests (4 per queue as for vdpa_sim_net) handled
in a batch to prevent the worker from using the CPU for too long.
Suggested-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
drivers/vdpa/vdpa_sim/vdpa_sim_blk.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
index a83a5c76f620..ac86478845b6 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim_blk.c
@@ -197,6 +197,7 @@ static bool vdpasim_blk_handle_req(struct vdpasim *vdpasim,
static void vdpasim_blk_work(struct work_struct *work)
{
struct vdpasim *vdpasim = container_of(work, struct vdpasim, work);
+ bool reschedule = false;
int i;
spin_lock(&vdpasim->lock);
@@ -206,11 +207,15 @@ static void vdpasim_blk_work(struct work_struct *work)
for (i = 0; i < VDPASIM_BLK_VQ_NUM; i++) {
struct vdpasim_virtqueue *vq = &vdpasim->vqs[i];
+ bool vq_work = true;
+ int reqs = 0;
if (!vq->ready)
continue;
- while (vdpasim_blk_handle_req(vdpasim, vq)) {
+ while (vq_work) {
+ vq_work = vdpasim_blk_handle_req(vdpasim, vq);
+
/* Make sure used is visible before rasing the interrupt. */
smp_wmb();
@@ -218,10 +223,18 @@ static void vdpasim_blk_work(struct work_struct *work)
if (vringh_need_notify_iotlb(&vq->vring) > 0)
vringh_notify(&vq->vring);
local_bh_enable();
+
+ if (++reqs > 4) {
+ vq_work = false;
+ reschedule = true;
+ }
}
}
out:
spin_unlock(&vdpasim->lock);
+
+ if (reschedule)
+ schedule_work(&vdpasim->work);
}
static void vdpasim_blk_get_config(struct vdpasim *vdpasim, void *config)
--
2.36.1
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