netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Olof Johansson <olof@lixom.net>
To: jgarzik@pobox.com
Cc: netdev@vger.kernel.org
Subject: [PATCH 7/9] pasemi_mac: Minor performance tweaks
Date: Fri, 22 Jun 2007 15:05:42 -0500	[thread overview]
Message-ID: <20070622200542.GH11723@lixom.net> (raw)
In-Reply-To: 20070622194720.614405000@lixom.net

[-- Attachment #1: pasemi_mac-rxperf --]
[-- Type: text/plain, Size: 2471 bytes --]

Various minor performance tweaks, do some explicit prefetching of packet
data, etc.

Signed-off-by: Olof Johansson <olof@lixom.net>

Index: netdev-2.6/drivers/net/pasemi_mac.c
===================================================================
--- netdev-2.6.orig/drivers/net/pasemi_mac.c
+++ netdev-2.6/drivers/net/pasemi_mac.c
@@ -481,6 +481,7 @@ static int pasemi_mac_clean_rx(struct pa
 		rmb();
 
 		dp = &RX_DESC(mac, n);
+		prefetchw(dp);
 		macrx = dp->macrx;
 
 		if (!(macrx & XCT_MACRX_O))
@@ -502,8 +503,10 @@ static int pasemi_mac_clean_rx(struct pa
 			if (info->dma == dma)
 				break;
 		}
+		prefetchw(info);
 
 		skb = info->skb;
+		prefetchw(skb);
 		info->dma = 0;
 
 		pci_unmap_single(mac->dma_pdev, dma, skb->len,
@@ -526,9 +529,7 @@ static int pasemi_mac_clean_rx(struct pa
 
 		skb_put(skb, len);
 
-		skb->protocol = eth_type_trans(skb, mac->netdev);
-
-		if ((macrx & XCT_MACRX_HTY_M) == XCT_MACRX_HTY_IPV4_OK) {
+		if (likely((macrx & XCT_MACRX_HTY_M) == XCT_MACRX_HTY_IPV4_OK)) {
 			skb->ip_summed = CHECKSUM_COMPLETE;
 			skb->csum = (macrx & XCT_MACRX_CSUM_M) >>
 					   XCT_MACRX_CSUM_S;
@@ -538,6 +539,7 @@ static int pasemi_mac_clean_rx(struct pa
 		mac->stats.rx_bytes += len;
 		mac->stats.rx_packets++;
 
+		skb->protocol = eth_type_trans(skb, mac->netdev);
 		netif_receive_skb(skb);
 
 		dp->ptr = 0;
@@ -569,7 +571,7 @@ static int pasemi_mac_clean_tx(struct pa
 
 	for (i = start; i < mac->tx->next_to_use; i++) {
 		dp = &TX_DESC(mac, i);
-		if (!dp || (dp->mactx & XCT_MACTX_O))
+		if (unlikely(dp->mactx & XCT_MACTX_O))
 			break;
 
 		count++;
@@ -957,7 +959,7 @@ static int pasemi_mac_start_tx(struct sk
 	struct pasemi_mac_txring *txring;
 	struct pasemi_mac_buffer *info;
 	struct pas_dma_xct_descr *dp;
-	u64 dflags;
+	u64 dflags, mactx, ptr;
 	dma_addr_t map;
 	int flags;
 
@@ -985,6 +987,9 @@ static int pasemi_mac_start_tx(struct sk
 	if (dma_mapping_error(map))
 		return NETDEV_TX_BUSY;
 
+	mactx = dflags | XCT_MACTX_LLEN(skb->len);
+	ptr   = XCT_PTR_LEN(skb->len) | XCT_PTR_ADDR(map);
+
 	txring = mac->tx;
 
 	spin_lock_irqsave(&txring->lock, flags);
@@ -1005,12 +1010,11 @@ static int pasemi_mac_start_tx(struct sk
 		}
 	}
 
-
 	dp = &TX_DESC(mac, txring->next_to_use);
 	info = &TX_DESC_INFO(mac, txring->next_to_use);
 
-	dp->mactx = dflags | XCT_MACTX_LLEN(skb->len);
-	dp->ptr   = XCT_PTR_LEN(skb->len) | XCT_PTR_ADDR(map);
+	dp->mactx = mactx;
+	dp->ptr = ptr;
 	info->dma = map;
 	info->skb = skb;
 

--

  parent reply	other threads:[~2007-06-22 20:07 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <20070622194720.614405000@lixom.net>
2007-06-22 20:04 ` [PATCH 1/9] pasemi_mac: Fix TX interrupt threshold Olof Johansson
2007-07-02 12:37   ` Jeff Garzik
2007-06-22 20:05 ` [PATCH 2/9] pasemi_mac: Clean TX ring in poll Olof Johansson
2007-07-02 12:34   ` Jeff Garzik
2007-07-03 20:31     ` Olof Johansson
2007-06-22 20:05 ` [PATCH 3/9] pasemi_mac: Abstract out register access Olof Johansson
2007-07-02 12:32   ` Jeff Garzik
2007-06-22 20:05 ` [PATCH 4/9] pasemi_mac: Use MMIO instead of pci config accessors Olof Johansson
2007-07-02 12:37   ` Jeff Garzik
2007-06-22 20:05 ` [PATCH 5/9] pasemi_mac: Enable L2 caching of packet headers Olof Johansson
2007-06-22 20:05 ` [PATCH 6/9] pasemi_mac: Simplify memcpy for short receives Olof Johansson
2007-06-22 20:05 ` Olof Johansson [this message]
2007-06-22 20:05 ` [PATCH 8/9] pasemi_mac: Reduce locking when cleaning TX ring Olof Johansson
2007-06-22 20:05 ` [PATCH 9/9] pasemi_mac: Enable LLTX Olof Johansson

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=20070622200542.GH11723@lixom.net \
    --to=olof@lixom.net \
    --cc=jgarzik@pobox.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).