Xuan Zhuo
2022-Aug-01 06:38 UTC
[PATCH v14 37/42] virtio_net: set the default max ring size by find_vqs()
Use virtio_find_vqs_ctx_size() to specify the maximum ring size of tx,
rx at the same time.
| rx/tx ring size
-------------------------------------------
speed == UNKNOWN or < 10G| 1024
speed < 40G | 4096
speed >= 40G | 8192
Call virtnet_update_settings() once before calling init_vqs() to update
speed.
Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com>
Acked-by: Jason Wang <jasowang at redhat.com>
---
drivers/net/virtio_net.c | 42 ++++++++++++++++++++++++++++++++++++----
1 file changed, 38 insertions(+), 4 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 8a5810bcb839..40532ecbe7fc 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -3208,6 +3208,29 @@ static unsigned int mergeable_min_buf_len(struct
virtnet_info *vi, struct virtqu
(unsigned int)GOOD_PACKET_LEN);
}
+static void virtnet_config_sizes(struct virtnet_info *vi, u32 *sizes)
+{
+ u32 i, rx_size, tx_size;
+
+ if (vi->speed == SPEED_UNKNOWN || vi->speed < SPEED_10000) {
+ rx_size = 1024;
+ tx_size = 1024;
+
+ } else if (vi->speed < SPEED_40000) {
+ rx_size = 1024 * 4;
+ tx_size = 1024 * 4;
+
+ } else {
+ rx_size = 1024 * 8;
+ tx_size = 1024 * 8;
+ }
+
+ for (i = 0; i < vi->max_queue_pairs; i++) {
+ sizes[rxq2vq(i)] = rx_size;
+ sizes[txq2vq(i)] = tx_size;
+ }
+}
+
static int virtnet_find_vqs(struct virtnet_info *vi)
{
vq_callback_t **callbacks;
@@ -3215,6 +3238,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
int ret = -ENOMEM;
int i, total_vqs;
const char **names;
+ u32 *sizes;
bool *ctx;
/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
@@ -3242,10 +3266,15 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
ctx = NULL;
}
+ sizes = kmalloc_array(total_vqs, sizeof(*sizes), GFP_KERNEL);
+ if (!sizes)
+ goto err_sizes;
+
/* Parameters for control virtqueue, if any */
if (vi->has_cvq) {
callbacks[total_vqs - 1] = NULL;
names[total_vqs - 1] = "control";
+ sizes[total_vqs - 1] = 64;
}
/* Allocate/initialize parameters for send/receive virtqueues */
@@ -3260,8 +3289,10 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
ctx[rxq2vq(i)] = true;
}
- ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks,
- names, ctx, NULL);
+ virtnet_config_sizes(vi, sizes);
+
+ ret = virtio_find_vqs_ctx_size(vi->vdev, total_vqs, vqs, callbacks,
+ names, sizes, ctx, NULL);
if (ret)
goto err_find;
@@ -3281,6 +3312,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi)
err_find:
+ kfree(sizes);
+err_sizes:
kfree(ctx);
err_ctx:
kfree(names);
@@ -3630,6 +3663,9 @@ static int virtnet_probe(struct virtio_device *vdev)
vi->curr_queue_pairs = num_online_cpus();
vi->max_queue_pairs = max_queue_pairs;
+ virtnet_init_settings(dev);
+ virtnet_update_settings(vi);
+
/* Allocate/initialize the rx/tx queues, and invoke find_vqs */
err = init_vqs(vi);
if (err)
@@ -3642,8 +3678,6 @@ static int virtnet_probe(struct virtio_device *vdev)
netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs);
netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs);
- virtnet_init_settings(dev);
-
if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) {
vi->failover = net_failover_create(vi->dev);
if (IS_ERR(vi->failover)) {
--
2.31.0
Michael S. Tsirkin
2022-Aug-15 06:00 UTC
[PATCH v14 37/42] virtio_net: set the default max ring size by find_vqs()
On Mon, Aug 01, 2022 at 02:38:57PM +0800, Xuan Zhuo wrote:> Use virtio_find_vqs_ctx_size() to specify the maximum ring size of tx, > rx at the same time. > > | rx/tx ring size > ------------------------------------------- > speed == UNKNOWN or < 10G| 1024 > speed < 40G | 4096 > speed >= 40G | 8192 > > Call virtnet_update_settings() once before calling init_vqs() to update > speed. > > Signed-off-by: Xuan Zhuo <xuanzhuo at linux.alibaba.com> > Acked-by: Jason Wang <jasowang at redhat.com>I've been looking at this patchset because of the resent reported crashes, and I'm having second thoughts about this. Do we really want to second-guess the device supplied max ring size? If yes why? Could you please share some performance data that motivated this specific set of numbers? Also why do we intepret UNKNOWN as "very low"? I'm thinking that should definitely be "don't change anything". Finally if all this makes sense then shouldn't we react when speed changes? Could you try reverting this and showing performance results before and after please? Thanks!> --- > drivers/net/virtio_net.c | 42 ++++++++++++++++++++++++++++++++++++---- > 1 file changed, 38 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c > index 8a5810bcb839..40532ecbe7fc 100644 > --- a/drivers/net/virtio_net.c > +++ b/drivers/net/virtio_net.c > @@ -3208,6 +3208,29 @@ static unsigned int mergeable_min_buf_len(struct virtnet_info *vi, struct virtqu > (unsigned int)GOOD_PACKET_LEN); > } > > +static void virtnet_config_sizes(struct virtnet_info *vi, u32 *sizes) > +{ > + u32 i, rx_size, tx_size; > + > + if (vi->speed == SPEED_UNKNOWN || vi->speed < SPEED_10000) { > + rx_size = 1024; > + tx_size = 1024; > + > + } else if (vi->speed < SPEED_40000) { > + rx_size = 1024 * 4; > + tx_size = 1024 * 4; > + > + } else { > + rx_size = 1024 * 8; > + tx_size = 1024 * 8; > + } > + > + for (i = 0; i < vi->max_queue_pairs; i++) { > + sizes[rxq2vq(i)] = rx_size; > + sizes[txq2vq(i)] = tx_size; > + } > +} > + > static int virtnet_find_vqs(struct virtnet_info *vi) > { > vq_callback_t **callbacks; > @@ -3215,6 +3238,7 @@ static int virtnet_find_vqs(struct virtnet_info *vi) > int ret = -ENOMEM; > int i, total_vqs; > const char **names; > + u32 *sizes; > bool *ctx; > > /* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by > @@ -3242,10 +3266,15 @@ static int virtnet_find_vqs(struct virtnet_info *vi) > ctx = NULL; > } > > + sizes = kmalloc_array(total_vqs, sizeof(*sizes), GFP_KERNEL); > + if (!sizes) > + goto err_sizes; > + > /* Parameters for control virtqueue, if any */ > if (vi->has_cvq) { > callbacks[total_vqs - 1] = NULL; > names[total_vqs - 1] = "control"; > + sizes[total_vqs - 1] = 64; > } > > /* Allocate/initialize parameters for send/receive virtqueues */ > @@ -3260,8 +3289,10 @@ static int virtnet_find_vqs(struct virtnet_info *vi) > ctx[rxq2vq(i)] = true; > } > > - ret = virtio_find_vqs_ctx(vi->vdev, total_vqs, vqs, callbacks, > - names, ctx, NULL); > + virtnet_config_sizes(vi, sizes); > + > + ret = virtio_find_vqs_ctx_size(vi->vdev, total_vqs, vqs, callbacks, > + names, sizes, ctx, NULL); > if (ret) > goto err_find; > > @@ -3281,6 +3312,8 @@ static int virtnet_find_vqs(struct virtnet_info *vi) > > > err_find: > + kfree(sizes); > +err_sizes: > kfree(ctx); > err_ctx: > kfree(names); > @@ -3630,6 +3663,9 @@ static int virtnet_probe(struct virtio_device *vdev) > vi->curr_queue_pairs = num_online_cpus(); > vi->max_queue_pairs = max_queue_pairs; > > + virtnet_init_settings(dev); > + virtnet_update_settings(vi); > + > /* Allocate/initialize the rx/tx queues, and invoke find_vqs */ > err = init_vqs(vi); > if (err) > @@ -3642,8 +3678,6 @@ static int virtnet_probe(struct virtio_device *vdev) > netif_set_real_num_tx_queues(dev, vi->curr_queue_pairs); > netif_set_real_num_rx_queues(dev, vi->curr_queue_pairs); > > - virtnet_init_settings(dev); > - > if (virtio_has_feature(vdev, VIRTIO_NET_F_STANDBY)) { > vi->failover = net_failover_create(vi->dev); > if (IS_ERR(vi->failover)) { > -- > 2.31.0