From: Jens Freimann <jfreimann@redhat.com>
To: Tiwei Bie <tiwei.bie@intel.com>
Cc: maxime.coquelin@redhat.com, zhihong.wang@intel.com, dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH 04/10] net/virtio: optimize flags update for packed ring
Date: Tue, 19 Mar 2019 09:54:03 +0100 [thread overview]
Message-ID: <20190319085403.gnamedd5pz7jzwvj@jenstp.localdomain> (raw)
Message-ID: <20190319085403.vcXma_vSkVJboJ7jn2RPGifWCfDsXUTT9zwlp6oP_YI@z> (raw)
In-Reply-To: <20190319064312.13743-5-tiwei.bie@intel.com>
On Tue, Mar 19, 2019 at 02:43:06PM +0800, Tiwei Bie wrote:
>Cache the AVAIL, USED and WRITE bits to avoid calculating
>them as much as possible. Note that, the WRITE bit isn't
>cached for control queue.
>
>Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
>---
> drivers/net/virtio/virtio_ethdev.c | 35 ++++++++++++++----------------
> drivers/net/virtio/virtio_rxtx.c | 31 ++++++++++----------------
> drivers/net/virtio/virtqueue.h | 8 +++----
> 3 files changed, 32 insertions(+), 42 deletions(-)
>
>diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
>index ff16fb63e..9060b6b33 100644
>--- a/drivers/net/virtio/virtio_ethdev.c
>+++ b/drivers/net/virtio/virtio_ethdev.c
>@@ -149,7 +149,7 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
> int head;
> struct vring_packed_desc *desc = vq->ring_packed.desc_packed;
> struct virtio_pmd_ctrl *result;
>- bool avail_wrap_counter;
>+ uint16_t flags;
> int sum = 0;
> int nb_descs = 0;
> int k;
>@@ -161,14 +161,15 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
> * One RX packet for ACK.
> */
> head = vq->vq_avail_idx;
>- avail_wrap_counter = vq->avail_wrap_counter;
>+ flags = vq->cached_flags;
> desc[head].addr = cvq->virtio_net_hdr_mem;
> desc[head].len = sizeof(struct virtio_net_ctrl_hdr);
> vq->vq_free_cnt--;
> nb_descs++;
> if (++vq->vq_avail_idx >= vq->vq_nentries) {
> vq->vq_avail_idx -= vq->vq_nentries;
>- vq->avail_wrap_counter ^= 1;
>+ vq->cached_flags ^=
>+ VRING_DESC_F_AVAIL(1) | VRING_DESC_F_USED(1);
Maybe name it avail_used_flags instead of cached flags. Also we could
use a constant value.
> }
>
> for (k = 0; k < pkt_num; k++) {
>@@ -177,34 +178,31 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
> + sizeof(ctrl->status) + sizeof(uint8_t) * sum;
> desc[vq->vq_avail_idx].len = dlen[k];
> desc[vq->vq_avail_idx].flags = VRING_DESC_F_NEXT |
>- VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
>- VRING_DESC_F_USED(!vq->avail_wrap_counter);
>+ vq->cached_flags;
> sum += dlen[k];
> vq->vq_free_cnt--;
> nb_descs++;
> if (++vq->vq_avail_idx >= vq->vq_nentries) {
> vq->vq_avail_idx -= vq->vq_nentries;
>- vq->avail_wrap_counter ^= 1;
>+ vq->cached_flags ^=
>+ VRING_DESC_F_AVAIL(1) | VRING_DESC_F_USED(1);
> }
> }
>
> desc[vq->vq_avail_idx].addr = cvq->virtio_net_hdr_mem
> + sizeof(struct virtio_net_ctrl_hdr);
> desc[vq->vq_avail_idx].len = sizeof(ctrl->status);
>- desc[vq->vq_avail_idx].flags = VRING_DESC_F_WRITE |
>- VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
>- VRING_DESC_F_USED(!vq->avail_wrap_counter);
>+ desc[vq->vq_avail_idx].flags = VRING_DESC_F_WRITE | vq->cached_flags;
> vq->vq_free_cnt--;
> nb_descs++;
> if (++vq->vq_avail_idx >= vq->vq_nentries) {
> vq->vq_avail_idx -= vq->vq_nentries;
>- vq->avail_wrap_counter ^= 1;
>+ vq->cached_flags ^=
>+ VRING_DESC_F_AVAIL(1) | VRING_DESC_F_USED(1);
> }
>
> virtio_wmb(vq->hw->weak_barriers);
>- desc[head].flags = VRING_DESC_F_NEXT |
>- VRING_DESC_F_AVAIL(avail_wrap_counter) |
>- VRING_DESC_F_USED(!avail_wrap_counter);
>+ desc[head].flags = VRING_DESC_F_NEXT | flags;
>
> virtio_wmb(vq->hw->weak_barriers);
> virtqueue_notify(vq);
>@@ -226,12 +224,12 @@ virtio_send_command_packed(struct virtnet_ctl *cvq,
> PMD_INIT_LOG(DEBUG, "vq->vq_free_cnt=%d\n"
> "vq->vq_avail_idx=%d\n"
> "vq->vq_used_cons_idx=%d\n"
>- "vq->avail_wrap_counter=%d\n"
>+ "vq->cached_flags=0x%x\n"
> "vq->used_wrap_counter=%d\n",
> vq->vq_free_cnt,
> vq->vq_avail_idx,
> vq->vq_used_cons_idx,
>- vq->avail_wrap_counter,
>+ vq->cached_flags,
> vq->used_wrap_counter);
>
> result = cvq->virtio_net_hdr_mz->addr;
>@@ -491,11 +489,10 @@ virtio_init_queue(struct rte_eth_dev *dev, uint16_t vtpci_queue_idx)
> vq->vq_nentries = vq_size;
> vq->event_flags_shadow = 0;
> if (vtpci_packed_queue(hw)) {
>- vq->avail_wrap_counter = 1;
> vq->used_wrap_counter = 1;
>- vq->avail_used_flags =
>- VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
>- VRING_DESC_F_USED(!vq->avail_wrap_counter);
>+ vq->cached_flags = VRING_DESC_F_AVAIL(1);
>+ if (queue_type == VTNET_RQ)
>+ vq->cached_flags |= VRING_DESC_F_WRITE;
> }
>
> /*
>diff --git a/drivers/net/virtio/virtio_rxtx.c b/drivers/net/virtio/virtio_rxtx.c
>index 771d3c3f6..3c354baef 100644
>--- a/drivers/net/virtio/virtio_rxtx.c
>+++ b/drivers/net/virtio/virtio_rxtx.c
>@@ -431,7 +431,7 @@ virtqueue_enqueue_recv_refill_packed(struct virtqueue *vq,
> struct rte_mbuf **cookie, uint16_t num)
> {
> struct vring_packed_desc *start_dp = vq->ring_packed.desc_packed;
>- uint16_t flags = VRING_DESC_F_WRITE | vq->avail_used_flags;
>+ uint16_t flags = vq->cached_flags;
> struct virtio_hw *hw = vq->hw;
> struct vq_desc_extra *dxp;
> uint16_t idx;
>@@ -460,11 +460,9 @@ virtqueue_enqueue_recv_refill_packed(struct virtqueue *vq,
> start_dp[idx].flags = flags;
> if (++vq->vq_avail_idx >= vq->vq_nentries) {
> vq->vq_avail_idx -= vq->vq_nentries;
>- vq->avail_wrap_counter ^= 1;
>- vq->avail_used_flags =
>- VRING_DESC_F_AVAIL(vq->avail_wrap_counter) |
>- VRING_DESC_F_USED(!vq->avail_wrap_counter);
>- flags = VRING_DESC_F_WRITE | vq->avail_used_flags;
>+ vq->cached_flags ^=
>+ VRING_DESC_F_AVAIL(1) | VRING_DESC_F_USED(1);
>+ flags = vq->cached_flags;
same here. it's not really cached, it's pre-calculated. And here we
could also use a pre-calculated constand/define.
Otherwise looks good! Did you see any performance improvements?
regards,
Jens
next prev parent reply other threads:[~2019-03-19 8:54 UTC|newest]
Thread overview: 88+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-19 6:43 [dpdk-dev] [PATCH 00/10] net/virtio: cleanups and fixes for packed/split ring Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 6:43 ` [dpdk-dev] [PATCH 01/10] net/virtio: fix typo in packed ring init Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 8:39 ` Jens Freimann
2019-03-19 8:39 ` Jens Freimann
2019-03-19 12:46 ` Maxime Coquelin
2019-03-19 12:46 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 02/10] net/virtio: fix interrupt helper for packed ring Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 12:48 ` Maxime Coquelin
2019-03-19 12:48 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 03/10] net/virtio: add missing barrier in interrupt enable Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 12:49 ` Maxime Coquelin
2019-03-19 12:49 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 04/10] net/virtio: optimize flags update for packed ring Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 8:54 ` Jens Freimann [this message]
2019-03-19 8:54 ` Jens Freimann
2019-03-19 9:37 ` Tiwei Bie
2019-03-19 9:37 ` Tiwei Bie
2019-03-19 10:11 ` Jens Freimann
2019-03-19 10:11 ` Jens Freimann
2019-03-19 12:50 ` Maxime Coquelin
2019-03-19 12:50 ` Maxime Coquelin
2019-03-19 12:58 ` Maxime Coquelin
2019-03-19 12:58 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 05/10] net/virtio: refactor virtqueue structure Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 9:44 ` Jens Freimann
2019-03-19 9:44 ` Jens Freimann
2019-03-19 10:09 ` Tiwei Bie
2019-03-19 10:09 ` Tiwei Bie
2019-03-19 13:28 ` Maxime Coquelin
2019-03-19 13:28 ` Maxime Coquelin
2019-03-19 13:47 ` Jens Freimann
2019-03-19 13:47 ` Jens Freimann
2019-03-19 13:50 ` Maxime Coquelin
2019-03-19 13:50 ` Maxime Coquelin
2019-03-19 14:59 ` Kevin Traynor
2019-03-19 14:59 ` Kevin Traynor
2019-03-20 4:40 ` Tiwei Bie
2019-03-20 4:40 ` Tiwei Bie
2019-03-20 17:50 ` Stephen Hemminger
2019-03-20 17:50 ` Stephen Hemminger
2019-03-21 14:18 ` Maxime Coquelin
2019-03-21 14:18 ` Maxime Coquelin
2019-03-20 4:35 ` Tiwei Bie
2019-03-20 4:35 ` Tiwei Bie
2019-03-19 13:28 ` Maxime Coquelin
2019-03-19 13:28 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 06/10] net/virtio: drop redundant suffix in packed ring structure Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 9:47 ` Jens Freimann
2019-03-19 9:47 ` Jens Freimann
2019-03-19 13:29 ` Maxime Coquelin
2019-03-19 13:29 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 07/10] net/virtio: drop unused field in Tx region structure Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 9:51 ` Jens Freimann
2019-03-19 9:51 ` Jens Freimann
2019-03-19 13:33 ` Maxime Coquelin
2019-03-19 13:33 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 08/10] net/virtio: add interrupt helper for split ring Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 9:53 ` Jens Freimann
2019-03-19 9:53 ` Jens Freimann
2019-03-19 13:34 ` Maxime Coquelin
2019-03-19 13:34 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 09/10] net/virtio: add ctrl vq " Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 9:54 ` Jens Freimann
2019-03-19 9:54 ` Jens Freimann
2019-03-19 13:54 ` Maxime Coquelin
2019-03-19 13:54 ` Maxime Coquelin
2019-03-19 6:43 ` [dpdk-dev] [PATCH 10/10] net/virtio: improve batching in standard Rx path Tiwei Bie
2019-03-19 6:43 ` Tiwei Bie
2019-03-19 10:04 ` Jens Freimann
2019-03-19 10:04 ` Jens Freimann
2019-03-19 10:28 ` Tiwei Bie
2019-03-19 10:28 ` Tiwei Bie
2019-03-19 11:08 ` Maxime Coquelin
2019-03-19 11:08 ` Maxime Coquelin
2019-03-19 14:15 ` Maxime Coquelin
2019-03-19 14:15 ` Maxime Coquelin
2019-03-20 7:35 ` [dpdk-dev] [PATCH 00/10] net/virtio: cleanups and fixes for packed/split ring Maxime Coquelin
2019-03-20 7:35 ` Maxime Coquelin
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