* [dpdk-dev] [PATCH v2] vhost: read last used index once
@ 2021-04-07 9:51 Balazs Nemeth
2021-04-07 9:55 ` [dpdk-dev] [PATCH v3] " Balazs Nemeth
0 siblings, 1 reply; 6+ messages in thread
From: Balazs Nemeth @ 2021-04-07 9:51 UTC (permalink / raw)
To: bnemeth, dev
Instead of calculating the address of a packed descriptor based on the
vq->desc_packed and vq->last_used_idx every time, store that base
address in desc_base. On arm, this saves 176 bytes in code size of
function in which vhost_flush_enqueue_batch_packed gets inlined.
Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
---
lib/librte_vhost/virtio_net.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 179c57b46..f091384a6 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -217,6 +217,8 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
{
uint16_t i;
uint16_t flags;
+ uint16_t last_used_idx = vq->last_used_idx;
+ struct vring_packed_desc *desc_base = &vq->desc_packed[last_used_idx];
if (vq->shadow_used_idx) {
do_data_copy_enqueue(dev, vq);
@@ -226,16 +228,17 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
flags = PACKED_DESC_ENQUEUE_USED_FLAG(vq->used_wrap_counter);
vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
- vq->desc_packed[vq->last_used_idx + i].id = ids[i];
- vq->desc_packed[vq->last_used_idx + i].len = lens[i];
+ desc_base[i].id = ids[i];
+ desc_base[i].len = lens[i];
}
rte_atomic_thread_fence(__ATOMIC_RELEASE);
- vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
- vq->desc_packed[vq->last_used_idx + i].flags = flags;
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ desc_base[i].flags = flags;
+ }
- vhost_log_cache_used_vring(dev, vq, vq->last_used_idx *
+ vhost_log_cache_used_vring(dev, vq, last_used_idx *
sizeof(struct vring_packed_desc),
sizeof(struct vring_packed_desc) *
PACKED_BATCH_SIZE);
--
2.30.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* [dpdk-dev] [PATCH v3] vhost: read last used index once
2021-04-07 9:51 [dpdk-dev] [PATCH v2] vhost: read last used index once Balazs Nemeth
@ 2021-04-07 9:55 ` Balazs Nemeth
2021-04-13 11:42 ` Maxime Coquelin
` (2 more replies)
0 siblings, 3 replies; 6+ messages in thread
From: Balazs Nemeth @ 2021-04-07 9:55 UTC (permalink / raw)
To: bnemeth, dev
Instead of calculating the address of a packed descriptor based on the
vq->desc_packed and vq->last_used_idx every time, store that base
address in desc_base. On arm, this saves 176 bytes in code size of
function in which vhost_flush_enqueue_batch_packed gets inlined.
Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
---
lib/librte_vhost/virtio_net.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
index 179c57b46..f091384a6 100644
--- a/lib/librte_vhost/virtio_net.c
+++ b/lib/librte_vhost/virtio_net.c
@@ -217,6 +217,8 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
{
uint16_t i;
uint16_t flags;
+ uint16_t last_used_idx = vq->last_used_idx;
+ struct vring_packed_desc *desc_base = &vq->desc_packed[last_used_idx];
if (vq->shadow_used_idx) {
do_data_copy_enqueue(dev, vq);
@@ -226,16 +228,17 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
flags = PACKED_DESC_ENQUEUE_USED_FLAG(vq->used_wrap_counter);
vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
- vq->desc_packed[vq->last_used_idx + i].id = ids[i];
- vq->desc_packed[vq->last_used_idx + i].len = lens[i];
+ desc_base[i].id = ids[i];
+ desc_base[i].len = lens[i];
}
rte_atomic_thread_fence(__ATOMIC_RELEASE);
- vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
- vq->desc_packed[vq->last_used_idx + i].flags = flags;
+ vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
+ desc_base[i].flags = flags;
+ }
- vhost_log_cache_used_vring(dev, vq, vq->last_used_idx *
+ vhost_log_cache_used_vring(dev, vq, last_used_idx *
sizeof(struct vring_packed_desc),
sizeof(struct vring_packed_desc) *
PACKED_BATCH_SIZE);
--
2.30.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] [PATCH v3] vhost: read last used index once
2021-04-07 9:55 ` [dpdk-dev] [PATCH v3] " Balazs Nemeth
@ 2021-04-13 11:42 ` Maxime Coquelin
2021-04-28 3:13 ` Xia, Chenbo
2021-05-08 8:43 ` Ling, WeiX
2 siblings, 0 replies; 6+ messages in thread
From: Maxime Coquelin @ 2021-04-13 11:42 UTC (permalink / raw)
To: Balazs Nemeth, dev
On 4/7/21 11:55 AM, Balazs Nemeth wrote:
> Instead of calculating the address of a packed descriptor based on the
> vq->desc_packed and vq->last_used_idx every time, store that base
> address in desc_base. On arm, this saves 176 bytes in code size of
> function in which vhost_flush_enqueue_batch_packed gets inlined.
>
> Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
> ---
> lib/librte_vhost/virtio_net.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
> index 179c57b46..f091384a6 100644
> --- a/lib/librte_vhost/virtio_net.c
> +++ b/lib/librte_vhost/virtio_net.c
> @@ -217,6 +217,8 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
> {
> uint16_t i;
> uint16_t flags;
> + uint16_t last_used_idx = vq->last_used_idx;
> + struct vring_packed_desc *desc_base = &vq->desc_packed[last_used_idx];
>
> if (vq->shadow_used_idx) {
> do_data_copy_enqueue(dev, vq);
> @@ -226,16 +228,17 @@ vhost_flush_enqueue_batch_packed(struct virtio_net *dev,
> flags = PACKED_DESC_ENQUEUE_USED_FLAG(vq->used_wrap_counter);
>
> vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> - vq->desc_packed[vq->last_used_idx + i].id = ids[i];
> - vq->desc_packed[vq->last_used_idx + i].len = lens[i];
> + desc_base[i].id = ids[i];
> + desc_base[i].len = lens[i];
> }
>
> rte_atomic_thread_fence(__ATOMIC_RELEASE);
>
> - vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
> - vq->desc_packed[vq->last_used_idx + i].flags = flags;
> + vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> + desc_base[i].flags = flags;
> + }
>
> - vhost_log_cache_used_vring(dev, vq, vq->last_used_idx *
> + vhost_log_cache_used_vring(dev, vq, last_used_idx *
> sizeof(struct vring_packed_desc),
> sizeof(struct vring_packed_desc) *
> PACKED_BATCH_SIZE);
>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>
Thanks,
Maxime
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] [PATCH v3] vhost: read last used index once
2021-04-07 9:55 ` [dpdk-dev] [PATCH v3] " Balazs Nemeth
2021-04-13 11:42 ` Maxime Coquelin
@ 2021-04-28 3:13 ` Xia, Chenbo
2021-05-08 8:43 ` Ling, WeiX
2 siblings, 0 replies; 6+ messages in thread
From: Xia, Chenbo @ 2021-04-28 3:13 UTC (permalink / raw)
To: Balazs Nemeth, dev
> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Balazs Nemeth
> Sent: Wednesday, April 7, 2021 5:55 PM
> To: bnemeth@redhat.com; dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v3] vhost: read last used index once
>
> Instead of calculating the address of a packed descriptor based on the
> vq->desc_packed and vq->last_used_idx every time, store that base
> address in desc_base. On arm, this saves 176 bytes in code size of
> function in which vhost_flush_enqueue_batch_packed gets inlined.
>
> Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
> ---
> lib/librte_vhost/virtio_net.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c
> index 179c57b46..f091384a6 100644
> --- a/lib/librte_vhost/virtio_net.c
> +++ b/lib/librte_vhost/virtio_net.c
> --
> 2.30.2
Patch applied to next-virtio/main, thanks
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] [PATCH v3] vhost: read last used index once
2021-04-07 9:55 ` [dpdk-dev] [PATCH v3] " Balazs Nemeth
2021-04-13 11:42 ` Maxime Coquelin
2021-04-28 3:13 ` Xia, Chenbo
@ 2021-05-08 8:43 ` Ling, WeiX
2021-05-10 7:08 ` Balazs Nemeth
2 siblings, 1 reply; 6+ messages in thread
From: Ling, WeiX @ 2021-05-08 8:43 UTC (permalink / raw)
To: Balazs Nemeth, dev
Hi Balazs Nemeth,
Your patch cause a bug about virtio-user can't recieve packets when use packed ring and ring size is 255.
Please have a look about it.
https://bugs.dpdk.org/show_bug.cgi?id=699
Thanks.
Regards,
Ling Wei
> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Balazs Nemeth
> Sent: Wednesday, April 7, 2021 05:55 PM
> To: bnemeth@redhat.com; dev@dpdk.org
> Subject: [dpdk-dev] [PATCH v3] vhost: read last used index once
>
> Instead of calculating the address of a packed descriptor based on the
> vq->desc_packed and vq->last_used_idx every time, store that base
> address in desc_base. On arm, this saves 176 bytes in code size of function in
> which vhost_flush_enqueue_batch_packed gets inlined.
>
> Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
> ---
> lib/librte_vhost/virtio_net.c | 13 ++++++++-----
> 1 file changed, 8 insertions(+), 5 deletions(-)
>
> diff --git a/lib/librte_vhost/virtio_net.c b/lib/librte_vhost/virtio_net.c index
> 179c57b46..f091384a6 100644
> --- a/lib/librte_vhost/virtio_net.c
> +++ b/lib/librte_vhost/virtio_net.c
> @@ -217,6 +217,8 @@ vhost_flush_enqueue_batch_packed(struct
> virtio_net *dev, {
> uint16_t i;
> uint16_t flags;
> + uint16_t last_used_idx = vq->last_used_idx;
> + struct vring_packed_desc *desc_base = &vq-
> >desc_packed[last_used_idx];
>
> if (vq->shadow_used_idx) {
> do_data_copy_enqueue(dev, vq);
> @@ -226,16 +228,17 @@ vhost_flush_enqueue_batch_packed(struct
> virtio_net *dev,
> flags = PACKED_DESC_ENQUEUE_USED_FLAG(vq-
> >used_wrap_counter);
>
> vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> - vq->desc_packed[vq->last_used_idx + i].id = ids[i];
> - vq->desc_packed[vq->last_used_idx + i].len = lens[i];
> + desc_base[i].id = ids[i];
> + desc_base[i].len = lens[i];
> }
>
> rte_atomic_thread_fence(__ATOMIC_RELEASE);
>
> - vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
> - vq->desc_packed[vq->last_used_idx + i].flags = flags;
> + vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> + desc_base[i].flags = flags;
> + }
>
> - vhost_log_cache_used_vring(dev, vq, vq->last_used_idx *
> + vhost_log_cache_used_vring(dev, vq, last_used_idx *
> sizeof(struct vring_packed_desc),
> sizeof(struct vring_packed_desc) *
> PACKED_BATCH_SIZE);
> --
> 2.30.2
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [dpdk-dev] [PATCH v3] vhost: read last used index once
2021-05-08 8:43 ` Ling, WeiX
@ 2021-05-10 7:08 ` Balazs Nemeth
0 siblings, 0 replies; 6+ messages in thread
From: Balazs Nemeth @ 2021-05-10 7:08 UTC (permalink / raw)
To: Ling, WeiX; +Cc: dev
Hi Ling,
I will take a look. Thanks for reporting.
Regards,
Balazs
On Sat, May 8, 2021 at 10:44 AM Ling, WeiX <weix.ling@intel.com> wrote:
> Hi Balazs Nemeth,
>
> Your patch cause a bug about virtio-user can't recieve packets when use
> packed ring and ring size is 255.
>
> Please have a look about it.
>
> https://bugs.dpdk.org/show_bug.cgi?id=699
>
> Thanks.
>
> Regards,
> Ling Wei
>
> > -----Original Message-----
> > From: dev <dev-bounces@dpdk.org> On Behalf Of Balazs Nemeth
> > Sent: Wednesday, April 7, 2021 05:55 PM
> > To: bnemeth@redhat.com; dev@dpdk.org
> > Subject: [dpdk-dev] [PATCH v3] vhost: read last used index once
> >
> > Instead of calculating the address of a packed descriptor based on the
> > vq->desc_packed and vq->last_used_idx every time, store that base
> > address in desc_base. On arm, this saves 176 bytes in code size of
> function in
> > which vhost_flush_enqueue_batch_packed gets inlined.
> >
> > Signed-off-by: Balazs Nemeth <bnemeth@redhat.com>
> > ---
> > lib/librte_vhost/virtio_net.c | 13 ++++++++-----
> > 1 file changed, 8 insertions(+), 5 deletions(-)
> >
> > diff --git a/lib/librte_vhost/virtio_net.c
> b/lib/librte_vhost/virtio_net.c index
> > 179c57b46..f091384a6 100644
> > --- a/lib/librte_vhost/virtio_net.c
> > +++ b/lib/librte_vhost/virtio_net.c
> > @@ -217,6 +217,8 @@ vhost_flush_enqueue_batch_packed(struct
> > virtio_net *dev, {
> > uint16_t i;
> > uint16_t flags;
> > + uint16_t last_used_idx = vq->last_used_idx;
> > + struct vring_packed_desc *desc_base = &vq-
> > >desc_packed[last_used_idx];
> >
> > if (vq->shadow_used_idx) {
> > do_data_copy_enqueue(dev, vq);
> > @@ -226,16 +228,17 @@ vhost_flush_enqueue_batch_packed(struct
> > virtio_net *dev,
> > flags = PACKED_DESC_ENQUEUE_USED_FLAG(vq-
> > >used_wrap_counter);
> >
> > vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> > - vq->desc_packed[vq->last_used_idx + i].id = ids[i];
> > - vq->desc_packed[vq->last_used_idx + i].len = lens[i];
> > + desc_base[i].id = ids[i];
> > + desc_base[i].len = lens[i];
> > }
> >
> > rte_atomic_thread_fence(__ATOMIC_RELEASE);
> >
> > - vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE)
> > - vq->desc_packed[vq->last_used_idx + i].flags = flags;
> > + vhost_for_each_try_unroll(i, 0, PACKED_BATCH_SIZE) {
> > + desc_base[i].flags = flags;
> > + }
> >
> > - vhost_log_cache_used_vring(dev, vq, vq->last_used_idx *
> > + vhost_log_cache_used_vring(dev, vq, last_used_idx *
> > sizeof(struct vring_packed_desc),
> > sizeof(struct vring_packed_desc) *
> > PACKED_BATCH_SIZE);
> > --
> > 2.30.2
>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2021-05-10 7:09 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-04-07 9:51 [dpdk-dev] [PATCH v2] vhost: read last used index once Balazs Nemeth
2021-04-07 9:55 ` [dpdk-dev] [PATCH v3] " Balazs Nemeth
2021-04-13 11:42 ` Maxime Coquelin
2021-04-28 3:13 ` Xia, Chenbo
2021-05-08 8:43 ` Ling, WeiX
2021-05-10 7:08 ` Balazs Nemeth
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).