patches for DPDK stable branches
 help / color / mirror / Atom feed
From: Lance Richardson <lance.richardson@broadcom.com>
To: Bruce Richardson <bruce.richardson@intel.com>,
	Konstantin Ananyev <konstantin.ananyev@intel.com>,
	Ajit Khaparde <ajit.khaparde@broadcom.com>,
	Somnath Kotur <somnath.kotur@broadcom.com>
Cc: dev@dpdk.org, stable@dpdk.org
Subject: [PATCH 1/2] net/bnxt: avoid unnecessary work in AVX2 Rx path
Date: Mon, 15 Nov 2021 13:24:09 -0500
Message-ID: <20211115182410.5545-2-lance.richardson@broadcom.com> (raw)
In-Reply-To: <20211115182410.5545-1-lance.richardson@broadcom.com>

[-- Attachment #1: Type: text/plain, Size: 1352 bytes --]

Each call to the AVX2 vector burst receive function makes at
least one pass through the function's inner loop, loading
256 bytes of completion descriptors and copying 8 rte_mbuf
pointers regardless of whether there are any packets to be
received.

Unidirectional forwarding performance is improved by about
3-4% if we ensure that at least one packet can be received
before entering the inner loop.

Fixes: c4e4c18963b0 ("net/bnxt: add AVX2 RX/Tx")
Cc: stable@dpdk.org
Signed-off-by: Lance Richardson <lance.richardson@broadcom.com>
---
 drivers/net/bnxt/bnxt_rxtx_vec_avx2.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/bnxt/bnxt_rxtx_vec_avx2.c b/drivers/net/bnxt/bnxt_rxtx_vec_avx2.c
index e4905b4fd1..54e3af22ac 100644
--- a/drivers/net/bnxt/bnxt_rxtx_vec_avx2.c
+++ b/drivers/net/bnxt/bnxt_rxtx_vec_avx2.c
@@ -98,6 +98,10 @@ recv_burst_vec_avx2(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts)
 	rte_prefetch0(&cp_desc_ring[cons + 8]);
 	rte_prefetch0(&cp_desc_ring[cons + 12]);
 
+	/* Return immediately if there is not at least one completed packet. */
+	if (!bnxt_cpr_cmp_valid(&cp_desc_ring[cons], raw_cons, cp_ring_size))
+		return 0;
+
 	/* Ensure that we do not go past the ends of the rings. */
 	nb_pkts = RTE_MIN(nb_pkts, RTE_MIN(rx_ring_size - mbcons,
 					   (cp_ring_size - cons) / 2));
-- 
2.25.1


[-- Attachment #2: S/MIME Cryptographic Signature --]
[-- Type: application/pkcs7-signature, Size: 4221 bytes --]

       reply	other threads:[~2021-11-15 18:24 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20211115182410.5545-1-lance.richardson@broadcom.com>
2021-11-15 18:24 ` Lance Richardson [this message]
2021-11-15 18:24 ` [PATCH 2/2] net/bnxt: remove software prefetches from " Lance Richardson

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=20211115182410.5545-2-lance.richardson@broadcom.com \
    --to=lance.richardson@broadcom.com \
    --cc=ajit.khaparde@broadcom.com \
    --cc=bruce.richardson@intel.com \
    --cc=dev@dpdk.org \
    --cc=konstantin.ananyev@intel.com \
    --cc=somnath.kotur@broadcom.com \
    --cc=stable@dpdk.org \
    /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

patches for DPDK stable branches

This inbox may be cloned and mirrored by anyone:

	git clone --mirror http://inbox.dpdk.org/stable/0 stable/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 stable stable/ http://inbox.dpdk.org/stable \
		stable@dpdk.org
	public-inbox-index stable

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.stable


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git