netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
To: davem@davemloft.net
Cc: netdev@vger.kernel.org, gospo@redhat.com,
	Wu Fengguang <fengguang.wu@intel.com>,
	Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Subject: [net-2.6 PATCH 1/2] ixgbe: fix tx queue index
Date: Tue, 14 Apr 2009 20:51:58 -0700	[thread overview]
Message-ID: <20090415035155.10107.6878.stgit@localhost.localdomain> (raw)

From: Wu Fengguang <fengguang.wu@intel.com>

Don't do the num_tx_queues based masking on calculating tx queue
index.

 1) num_tx_queues is not always power-of-2, because it also depends on
    the online cpu numbers. So the masking could be a performance bug
    on a 6 cpu system.
 2) queue_mapping will be limited by real_num_tx_queues=num_tx_queues
    in the generic netdev function set_cur_queue_map(). So the bound
    limiting here is not necessary.

Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---

 drivers/net/ixgbe/ixgbe_main.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/net/ixgbe/ixgbe_main.c b/drivers/net/ixgbe/ixgbe_main.c
index 9ef128a..862dd34 100644
--- a/drivers/net/ixgbe/ixgbe_main.c
+++ b/drivers/net/ixgbe/ixgbe_main.c
@@ -4342,7 +4342,7 @@ static int ixgbe_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
 	int count = 0;
 	unsigned int f;
 
-	r_idx = (adapter->num_tx_queues - 1) & skb->queue_mapping;
+	r_idx = skb->queue_mapping;
 	tx_ring = &adapter->tx_ring[r_idx];
 
 	if (adapter->vlgrp && vlan_tx_tag_present(skb)) {


             reply	other threads:[~2009-04-15  3:52 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-15  3:51 Jeff Kirsher [this message]
2009-04-15  3:52 ` [net-2.6 PATCH 2/2] ixgbe: update real_num_tx_queues on changing num_rx_queues Jeff Kirsher
2009-04-15  4:54   ` David Miller
2009-04-15  4:54 ` [net-2.6 PATCH 1/2] ixgbe: fix tx queue index David Miller

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=20090415035155.10107.6878.stgit@localhost.localdomain \
    --to=jeffrey.t.kirsher@intel.com \
    --cc=davem@davemloft.net \
    --cc=fengguang.wu@intel.com \
    --cc=gospo@redhat.com \
    --cc=netdev@vger.kernel.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
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).