From: "Dmitry Kravkov" <dmitry@broadcom.com>
To: davem@davemloft.net, netdev@vger.kernel.org
Cc: "Dmitry Kravkov" <dmitry@broadcom.com>,
"Eilon Greenstein" <eilong@broadcom.com>,
"Eric Dumazet" <edumazet@google.com>
Subject: [PATCH net-next] bnx2x: organize BDs calculation for stop/resume
Date: Tue, 26 Jun 2012 11:32:50 +0300 [thread overview]
Message-ID: <1340699570-17735-1-git-send-email-dmitry@broadcom.com> (raw)
Put the numbers used for stop/resume queue in a single place and
fix the condition for sanity check.
Signed-off-by: Dmitry Kravkov <dmitry@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Cc: Eric Dumazet <edumazet@google.com>
---
drivers/net/ethernet/broadcom/bnx2x/bnx2x.h | 16 ++++++++++++++++
drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c | 10 ++++++----
2 files changed, 22 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
index 7211cb0..392fffe 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x.h
@@ -612,6 +612,22 @@ struct bnx2x_fastpath {
#define TX_BD(x) ((x) & MAX_TX_BD)
#define TX_BD_POFF(x) ((x) & MAX_TX_DESC_CNT)
+/* number of NEXT_PAGE descriptors may be required during placement */
+#define NEXT_CNT_PER_TX_PKT(bds) \
+ (((bds) + MAX_TX_DESC_CNT - 1) / \
+ MAX_TX_DESC_CNT * NEXT_PAGE_TX_DESC_CNT)
+/* max BDs per tx packet w/o next_pages:
+ * START_BD - describes packed
+ * START_BD(splitted) - includes unpaged data segment for GSO
+ * PARSING_BD - for TSO and CSUM data
+ * Frag BDs - decribes pages for frags
+ */
+#define BDS_PER_TX_PKT 3
+#define MAX_BDS_PER_TX_PKT (MAX_SKB_FRAGS + BDS_PER_TX_PKT)
+/* max BDs per tx packet including next pages */
+#define MAX_DESC_PER_TX_PKT (MAX_BDS_PER_TX_PKT + \
+ NEXT_CNT_PER_TX_PKT(MAX_BDS_PER_TX_PKT))
+
/* The RX BD ring is special, each bd is 8 bytes but the last one is 16 */
#define NUM_RX_RINGS 8
#define RX_DESC_CNT (BCM_PAGE_SIZE / sizeof(struct eth_rx_bd))
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
index 00951b3..e357a5d 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_cmn.c
@@ -221,7 +221,7 @@ int bnx2x_tx_int(struct bnx2x *bp, struct bnx2x_fp_txdata *txdata)
if ((netif_tx_queue_stopped(txq)) &&
(bp->state == BNX2X_STATE_OPEN) &&
- (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 4))
+ (bnx2x_tx_avail(bp, txdata) >= MAX_DESC_PER_TX_PKT))
netif_tx_wake_queue(txq);
__netif_tx_unlock(txq);
@@ -2937,7 +2937,9 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
txdata->cid, fp_index, txdata_index, txdata, fp); */
if (unlikely(bnx2x_tx_avail(bp, txdata) <
- (skb_shinfo(skb)->nr_frags + 3))) {
+ skb_shinfo(skb)->nr_frags +
+ BDS_PER_TX_PKT +
+ NEXT_CNT_PER_TX_PKT(MAX_BDS_PER_TX_PKT))) {
bnx2x_fp_qstats(bp, txdata->parent_fp)->driver_xoff++;
netif_tx_stop_queue(txq);
BNX2X_ERR("BUG! Tx ring full when queue awake!\n");
@@ -3212,7 +3214,7 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
txdata->tx_bd_prod += nbd;
- if (unlikely(bnx2x_tx_avail(bp, txdata) < MAX_SKB_FRAGS + 4)) {
+ if (unlikely(bnx2x_tx_avail(bp, txdata) < MAX_DESC_PER_TX_PKT)) {
netif_tx_stop_queue(txq);
/* paired memory barrier is in bnx2x_tx_int(), we have to keep
@@ -3221,7 +3223,7 @@ netdev_tx_t bnx2x_start_xmit(struct sk_buff *skb, struct net_device *dev)
smp_mb();
bnx2x_fp_qstats(bp, txdata->parent_fp)->driver_xoff++;
- if (bnx2x_tx_avail(bp, txdata) >= MAX_SKB_FRAGS + 4)
+ if (bnx2x_tx_avail(bp, txdata) >= MAX_DESC_PER_TX_PKT)
netif_tx_wake_queue(txq);
}
txdata->tx_pkt++;
--
1.7.1
reply other threads:[~2012-06-26 8:33 UTC|newest]
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