| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1454016364-30985-36-git-send-email-troy.kisky@boundarydevices.com>
Date: Thu, 28 Jan 2016 14:25:59 -0700
From: Troy Kisky <troy.kisky@...ndarydevices.com>
To: netdev@...r.kernel.org, davem@...emloft.net, B38611@...escale.com
Cc: fabio.estevam@...escale.com, l.stach@...gutronix.de,
andrew@...n.ch, tremyfr@...il.com, linux@....linux.org.uk,
linux-arm-kernel@...ts.infradead.org, laci@...ndarydevices.com,
shawnguo@...nel.org, Troy Kisky <troy.kisky@...ndarydevices.com>
Subject: [PATCH net-next 35/40] net: fec: rename dirty_tx to pending_tx
dirty_tx always pointed to the last entry that was
trasmitted. pending_tx always points to the next entry
to be transmitted. This should be a little more efficient.
This will allow 1 more entry in the queue to be used.
That is, ring_size -1 entries instead of ring_size -2.
This also allows the removal of fec_enet_get_prevdesc.
Signed-off-by: Troy Kisky <troy.kisky@...ndarydevices.com>
---
drivers/net/ethernet/freescale/fec.h | 14 +++++-------
drivers/net/ethernet/freescale/fec_main.c | 38 ++++++++++---------------------
2 files changed, 18 insertions(+), 34 deletions(-)
diff --git a/drivers/net/ethernet/freescale/fec.h b/drivers/net/ethernet/freescale/fec.h
index d2ca2e2..a16e47e 100644
--- a/drivers/net/ethernet/freescale/fec.h
+++ b/drivers/net/ethernet/freescale/fec.h
@@ -440,6 +440,10 @@ struct bufdesc_prop {
unsigned char dsize_log2;
};
+/* bd.cur points to the currently available buffer.
+ * pending_tx tracks the current buffer that is being sent by the
+ * controller. When bd.cur and pending_tx are equal, nothing is pending.
+ */
struct fec_enet_priv_tx_q {
struct bufdesc_prop bd;
unsigned char *tx_bounce[TX_RING_SIZE];
@@ -448,7 +452,7 @@ struct fec_enet_priv_tx_q {
unsigned short tx_stop_threshold;
unsigned short tx_wake_threshold;
- struct bufdesc *dirty_tx;
+ struct bufdesc *pending_tx;
char *tso_hdrs;
dma_addr_t tso_hdrs_dma;
};
@@ -458,13 +462,7 @@ struct fec_enet_priv_rx_q {
struct sk_buff *rx_skbuff[RX_RING_SIZE];
};
-/* The FEC buffer descriptors track the ring buffers. The rx_bd_base and
- * tx_bd_base always point to the base of the buffer descriptors. The
- * cur_rx and cur_tx point to the currently available buffer.
- * The dirty_tx tracks the current buffer that is being sent by the
- * controller. The cur_tx and dirty_tx are equal under both completely
- * empty and completely full conditions. The empty/ready indicator in
- * the buffer descriptor determines the actual condition.
+/* The FEC buffer descriptors track the ring buffers.
*/
struct fec_enet_private {
/* Hardware registers of the FEC device */
diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index 8dea600..9db645d 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -226,13 +226,6 @@ static struct bufdesc *fec_enet_get_nextdesc(struct bufdesc *bdp,
: (struct bufdesc *)(((unsigned)bdp) + bd->dsize);
}
-static struct bufdesc *fec_enet_get_prevdesc(struct bufdesc *bdp,
- struct bufdesc_prop *bd)
-{
- return (bdp <= bd->base) ? bd->last
- : (struct bufdesc *)(((unsigned)bdp) - bd->dsize);
-}
-
static int fec_enet_get_bd_index(struct bufdesc *bdp,
struct bufdesc_prop *bd)
{
@@ -243,7 +236,7 @@ static int fec_enet_get_free_txdesc_num(struct fec_enet_priv_tx_q *txq)
{
int entries;
- entries = (((const char *)txq->dirty_tx -
+ entries = (((const char *)txq->pending_tx -
(const char *)txq->bd.cur) >> txq->bd.dsize_log2) - 1;
return entries >= 0 ? entries : entries + txq->bd.ring_size;
@@ -288,7 +281,7 @@ static void fec_dump(struct net_device *ndev)
pr_info("%3u %c%c 0x%04x 0x%08lx %4u %p\n",
index,
bdp == txq->bd.cur ? 'S' : ' ',
- bdp == txq->dirty_tx ? 'H' : ' ',
+ bdp == txq->pending_tx ? 'H' : ' ',
bdp->cbd_sc, bdp->cbd_bufaddr, bdp->cbd_datlen,
txq->tx_skbuff[index]);
bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
@@ -802,6 +795,7 @@ static void fec_enet_bd_init(struct net_device *dev)
txq = fep->tx_queue[q];
bdp = txq->bd.base;
txq->bd.cur = bdp;
+ txq->pending_tx = bdp;
for (i = 0; i < txq->bd.ring_size; i++) {
/* Initialize the BD for every fragment in the page. */
@@ -820,8 +814,6 @@ static void fec_enet_bd_init(struct net_device *dev)
bdp->cbd_sc = (bdp == txq->bd.last) ? BD_SC_WRAP : 0;
bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
}
- bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
- txq->dirty_tx = bdp;
}
}
@@ -1134,11 +1126,8 @@ fec_timeout(struct net_device *ndev)
int index;
struct sk_buff *skb = NULL;
- bdp = txq->dirty_tx;
- while (1) {
- bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
- if (bdp == txq->bd.cur)
- break;
+ bdp = txq->pending_tx;
+ while (bdp != txq->bd.cur) {
index = fec_enet_get_bd_index(bdp, &txq->bd);
skb = txq->tx_skbuff[index];
if (skb) {
@@ -1147,6 +1136,7 @@ fec_timeout(struct net_device *ndev)
events |= txint_flags[i];
break;
}
+ bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
}
}
if (events) {
@@ -1208,12 +1198,8 @@ static void fec_txq(struct net_device *ndev, struct fec_enet_private *fep,
int index = 0;
int entries_free;
- /* get next bdp of dirty_tx */
nq = netdev_get_tx_queue(ndev, txq->bd.qid);
- bdp = txq->dirty_tx;
-
- /* get next bdp of dirty_tx */
- bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
+ bdp = txq->pending_tx;
while (bdp != READ_ONCE(txq->bd.cur)) {
/* Order the load of bd.cur and cbd_sc */
@@ -1277,14 +1263,14 @@ static void fec_txq(struct net_device *ndev, struct fec_enet_private *fep,
/* Free the sk buffer associated with this last transmit */
dev_kfree_skb_any(skb);
skb_done:
+ /* Update pointer to next buffer descriptor to be transmitted */
+ bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
+
/* Make sure the update to bdp and tx_skbuff are performed
- * before dirty_tx
+ * before pending_tx
*/
wmb();
- txq->dirty_tx = bdp;
-
- /* Update pointer to next buffer descriptor to be transmitted */
- bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
+ txq->pending_tx = bdp;
/* Since we have freed up a buffer, the ring is no longer full
*/
--
2.5.0
Powered by blists - more mailing lists