[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1375712410-11760-3-git-send-email-claudiu.manoil@freescale.com>
Date: Mon, 5 Aug 2013 17:20:10 +0300
From: Claudiu Manoil <claudiu.manoil@...escale.com>
To: <netdev@...r.kernel.org>
CC: "David S. Miller" <davem@...emloft.net>,
Paul Gortmaker <paul.gortmaker@...driver.com>
Subject: [PATCH 2/2][net-next] gianfar: Cleanup TxFCB insertion on xmit
Cleanup gfar_start_xmit()'s fast path by factoring out "redundant"
FCB insertion code (repeated gfar_add_fcb() calls and related)
and by reducing the number of if() clauses (i.e. if(fcb) checks).
Improve maintainability (e.g. there's less code and easier to read)
also by introducing do_csum and do_vlan to mark the other 2 Tx TOE
functionalities, following the same model as do_tstamp.
fcb_len may also be 0 now, to mark that Tx FCB insertion conditions
(do_csum, do_vlan, do_tstamp) have not been met.
Signed-off-by: Claudiu Manoil <claudiu.manoil@...escale.com>
---
drivers/net/ethernet/freescale/gianfar.c | 62 +++++++++++++++++---------------
1 file changed, 33 insertions(+), 29 deletions(-)
diff --git a/drivers/net/ethernet/freescale/gianfar.c b/drivers/net/ethernet/freescale/gianfar.c
index 3a543f7..d4f22c6 100644
--- a/drivers/net/ethernet/freescale/gianfar.c
+++ b/drivers/net/ethernet/freescale/gianfar.c
@@ -2084,10 +2084,11 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
struct txfcb *fcb = NULL;
struct txbd8 *txbdp, *txbdp_start, *base, *txbdp_tstamp = NULL;
u32 lstatus;
- int i, rq = 0, do_tstamp = 0;
+ int i, rq = 0;
+ int do_tstamp, do_csum, do_vlan;
u32 bufaddr;
unsigned long flags;
- unsigned int nr_frags, nr_txbds, length, fcb_length = GMAC_FCB_LEN;
+ unsigned int nr_frags, nr_txbds, length, fcb_len = 0;
rq = skb->queue_mapping;
tx_queue = priv->tx_queue[rq];
@@ -2095,21 +2096,23 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
base = tx_queue->tx_bd_base;
regs = tx_queue->grp->regs;
+ do_csum = (CHECKSUM_PARTIAL == skb->ip_summed);
+ do_vlan = vlan_tx_tag_present(skb);
+ do_tstamp = (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
+ priv->hwts_tx_en;
+
+ if (do_csum || do_vlan)
+ fcb_len = GMAC_FCB_LEN;
+
/* check if time stamp should be generated */
- if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
- priv->hwts_tx_en)) {
- do_tstamp = 1;
- fcb_length = GMAC_FCB_LEN + GMAC_TXPAL_LEN;
- }
+ if (unlikely(do_tstamp))
+ fcb_len = GMAC_FCB_LEN + GMAC_TXPAL_LEN;
/* make space for additional header when fcb is needed */
- if (((skb->ip_summed == CHECKSUM_PARTIAL) ||
- vlan_tx_tag_present(skb) ||
- unlikely(do_tstamp)) &&
- (skb_headroom(skb) < fcb_length)) {
+ if (fcb_len && unlikely(skb_headroom(skb) < fcb_len)) {
struct sk_buff *skb_new;
- skb_new = skb_realloc_headroom(skb, fcb_length);
+ skb_new = skb_realloc_headroom(skb, fcb_len);
if (!skb_new) {
dev->stats.tx_errors++;
kfree_skb(skb);
@@ -2192,37 +2195,38 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
memset(skb->data, 0, GMAC_TXPAL_LEN);
}
- /* Set up checksumming */
- if (CHECKSUM_PARTIAL == skb->ip_summed) {
+ /* Add TxFCB if required */
+ if (fcb_len) {
fcb = gfar_add_fcb(skb);
lstatus |= BD_LFLAG(TXBD_TOE);
- gfar_tx_checksum(skb, fcb, fcb_length);
+ }
+
+ /* Set up checksumming */
+ if (do_csum) {
+ gfar_tx_checksum(skb, fcb, fcb_len);
if (unlikely(gfar_csum_errata_12(priv, (unsigned long)fcb)) ||
unlikely(gfar_csum_errata_76(priv, skb->len))) {
__skb_pull(skb, GMAC_FCB_LEN);
skb_checksum_help(skb);
- lstatus &= ~(BD_LFLAG(TXBD_TOE));
- fcb = NULL;
+ if (do_vlan || do_tstamp) {
+ /* put back a new fcb for vlan/tstamp TOE */
+ fcb = gfar_add_fcb(skb);
+ } else {
+ /* Tx TOE not used */
+ lstatus &= ~(BD_LFLAG(TXBD_TOE));
+ fcb = NULL;
+ }
}
}
- if (vlan_tx_tag_present(skb)) {
- if (unlikely(NULL == fcb)) {
- fcb = gfar_add_fcb(skb);
- lstatus |= BD_LFLAG(TXBD_TOE);
- }
-
+ if (do_vlan)
gfar_tx_vlan(skb, fcb);
- }
/* Setup tx hardware time stamping if requested */
if (unlikely(do_tstamp)) {
skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
- if (fcb == NULL)
- fcb = gfar_add_fcb(skb);
fcb->ptp = 1;
- lstatus |= BD_LFLAG(TXBD_TOE);
}
txbdp_start->bufPtr = dma_map_single(priv->dev, skb->data,
@@ -2234,9 +2238,9 @@ static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
* the full frame length.
*/
if (unlikely(do_tstamp)) {
- txbdp_tstamp->bufPtr = txbdp_start->bufPtr + fcb_length;
+ txbdp_tstamp->bufPtr = txbdp_start->bufPtr + fcb_len;
txbdp_tstamp->lstatus |= BD_LFLAG(TXBD_READY) |
- (skb_headlen(skb) - fcb_length);
+ (skb_headlen(skb) - fcb_len);
lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | GMAC_FCB_LEN;
} else {
lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | skb_headlen(skb);
--
1.7.11.7
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists