DPDK patches and discussions
 help / color / mirror / Atom feed
From: Ye Xiaolong <xiaolong.ye@intel.com>
To: Gavin Hu <gavin.hu@arm.com>
Cc: dev@dpdk.org, nd@arm.com, david.marchand@redhat.com,
	thomas@monjalon.net, rasland@mellanox.com,
	maxime.coquelin@redhat.com, tiwei.bie@intel.com,
	matan@mellanox.com, shahafs@mellanox.com,
	viacheslavo@mellanox.com, arybchenko@solarflare.com,
	stephen@networkplumber.org, hemant.agrawal@nxp.com,
	jerinj@marvell.com, pbhagavatula@marvell.com,
	Honnappa.Nagarahalli@arm.com, ruifeng.wang@arm.com,
	phil.yang@arm.com, joyce.kong@arm.com, steve.capper@arm.com
Subject: Re: [dpdk-dev] [PATCH v3] net/i40e: relaxed barrier in the tx fastpath
Date: Tue, 11 Feb 2020 10:11:09 +0800	[thread overview]
Message-ID: <20200211021109.GH80720@intel.com> (raw)
In-Reply-To: <20200208134808.212027-1-gavin.hu@arm.com>

Hi, Gavin

Please help add the Fixes tag and cc stable.

Thanks,
Xiaolong

On 02/08, Gavin Hu wrote:
>To keep ordering of mixed accesses, rte_cio is sufficient.
>The rte_io barrier is overkill.[1]
>
>[1] http://inbox.dpdk.org/dev/CALBAE1M-ezVWCjqCZDBw+MMDEC4O9
>qf0Kpn89EMdGDajepKoZQ@mail.gmail.com
>
>Signed-off-by: Gavin Hu <gavin.hu@arm.com>
>---
>V3:
>- optimize the barriers in the fast path only, leave as it is for the
>  barriers in the slow path and control path <jerin>
>- drop the virtio patches from the list as they are in the control path
>- it makes more sense to relax the barrier in the fast path, at the PMD level.
>  relaxing the fundamental rte_io_x barriers APIs requires scrutinizations for
>  each PMDs which use the barriers directly or indirectly.
>V2:
>- remove virtio_pci_read/write64 APIs definitions, they are not needed and generate compiling errors like " error: unused function 'virtio_pci_write64' [-Werror,-Wunused-function]"
>- update the reference link to kernel source code
>---
> drivers/net/i40e/i40e_rxtx.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
>diff --git a/drivers/net/i40e/i40e_rxtx.c b/drivers/net/i40e/i40e_rxtx.c
>index fd1ae80da..8c0f7cc67 100644
>--- a/drivers/net/i40e/i40e_rxtx.c
>+++ b/drivers/net/i40e/i40e_rxtx.c
>@@ -1248,7 +1248,8 @@ i40e_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
> 		   (unsigned) txq->port_id, (unsigned) txq->queue_id,
> 		   (unsigned) tx_id, (unsigned) nb_tx);
> 
>-	I40E_PCI_REG_WRITE(txq->qtx_tail, tx_id);
>+	rte_cio_wmb();
>+	I40E_PCI_REG_WRITE_RELAXED(txq->qtx_tail, tx_id);
> 	txq->tx_tail = tx_id;
> 
> 	return nb_tx;
>-- 
>2.17.1
>

  reply	other threads:[~2020-02-11  2:12 UTC|newest]

Thread overview: 34+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-10-22 15:27 [dpdk-dev] [PATCH v1 0/3] relax io barrier for aarch64 and use smp barriers for virtual pci memory Gavin Hu
2019-10-22 15:27 ` [dpdk-dev] [PATCH v1 1/3] eal/arm64: relax the io barrier for aarch64 Gavin Hu
2019-10-22 15:27 ` [dpdk-dev] [PATCH v1 2/3] net/virtio: virtual PCI requires smp barriers Gavin Hu
2019-10-22 15:27 ` [dpdk-dev] [PATCH v1 3/3] crypto/virtio: " Gavin Hu
2019-10-23  8:22 ` [dpdk-dev] [PATCH v1 0/3] relax io barrier for aarch64 and use smp barriers for virtual pci memory Maxime Coquelin
2019-11-07  1:13   ` Gavin Hu (Arm Technology China)
2019-12-20  3:09 ` [dpdk-dev] [PATCH v2 " Gavin Hu
2019-12-20  3:09 ` [dpdk-dev] [PATCH v2 1/3] eal/arm64: relax the io barrier for aarch64 Gavin Hu
2019-12-20  3:33   ` Jerin Jacob
2019-12-20  3:38     ` Jerin Jacob
2019-12-20  4:19       ` Gavin Hu
2019-12-20  4:34         ` Jerin Jacob
2019-12-20  6:32           ` Gavin Hu
2019-12-20  6:55             ` Jerin Jacob
2019-12-23  9:14               ` Gavin Hu
2019-12-23  9:19                 ` Jerin Jacob
2019-12-23 10:16                   ` Gavin Hu
2020-01-02  9:51                     ` Jerin Jacob
2020-01-03  6:30                       ` Gavin Hu
2020-01-03  7:34                         ` Jerin Jacob
2020-01-03  9:12                           ` Gavin Hu
2019-12-20  3:09 ` [dpdk-dev] [PATCH v2 2/3] net/virtio: virtual PCI requires smp barriers Gavin Hu
2019-12-20  8:17   ` Tiwei Bie
2019-12-20 10:19     ` Gavin Hu
2019-12-20  3:09 ` [dpdk-dev] [PATCH v2 3/3] crypto/virtio: " Gavin Hu
2020-02-08 13:48 ` [dpdk-dev] [PATCH v3] net/i40e: relaxed barrier in the tx fastpath Gavin Hu
2020-02-11  2:11   ` Ye Xiaolong [this message]
2020-02-12  6:02     ` Gavin Hu
2020-02-15  8:25   ` Jerin Jacob
2020-02-12  5:56 ` [dpdk-dev] [PATCH v4] " Gavin Hu
2020-02-15 15:16   ` Ye Xiaolong
2020-02-16  9:51     ` Thomas Monjalon
2020-02-16 16:38       ` Ye Xiaolong
2020-02-16 17:36         ` Thomas Monjalon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200211021109.GH80720@intel.com \
    --to=xiaolong.ye@intel.com \
    --cc=Honnappa.Nagarahalli@arm.com \
    --cc=arybchenko@solarflare.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=gavin.hu@arm.com \
    --cc=hemant.agrawal@nxp.com \
    --cc=jerinj@marvell.com \
    --cc=joyce.kong@arm.com \
    --cc=matan@mellanox.com \
    --cc=maxime.coquelin@redhat.com \
    --cc=nd@arm.com \
    --cc=pbhagavatula@marvell.com \
    --cc=phil.yang@arm.com \
    --cc=rasland@mellanox.com \
    --cc=ruifeng.wang@arm.com \
    --cc=shahafs@mellanox.com \
    --cc=stephen@networkplumber.org \
    --cc=steve.capper@arm.com \
    --cc=thomas@monjalon.net \
    --cc=tiwei.bie@intel.com \
    --cc=viacheslavo@mellanox.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
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).