[PATCH 9/9] cxgb3 - Fix I/O synchronization

From: Divy Le Ray
Date: Fri Nov 16 2007 - 14:25:46 EST


From: Divy Le Ray <divy@xxxxxxxxxxx>

Synchronize memory access before ringing
the Tx door bell.

Signed-off-by: Divy Le Ray <divy@xxxxxxxxxxx>
---

drivers/net/cxgb3/sge.c | 7 +++++--
1 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/net/cxgb3/sge.c b/drivers/net/cxgb3/sge.c
index 7b13d8a..666c317 100644
--- a/drivers/net/cxgb3/sge.c
+++ b/drivers/net/cxgb3/sge.c
@@ -174,6 +174,7 @@ static inline struct sge_qset *txq_to_qset(const struct sge_txq *q, int qidx)
static inline void refill_rspq(struct adapter *adapter,
const struct sge_rspq *q, unsigned int credits)
{
+ rmb();
t3_write_reg(adapter, A_SG_RSPQ_CREDIT_RETURN,
V_RSPQ(q->cntxt_id) | V_CREDITS(credits));
}
@@ -458,7 +459,7 @@ nomem: q->alloc_failed++;
}
q->credits++;
}
-
+ wmb();
t3_write_reg(adap, A_SG_KDOORBELL, V_EGRCNTX(q->cntxt_id));
}

@@ -1353,6 +1354,7 @@ static void restart_ctrlq(unsigned long data)
}

spin_unlock(&q->lock);
+ wmb();
t3_write_reg(qs->adap, A_SG_KDOORBELL,
F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
}
@@ -1572,6 +1574,7 @@ static void restart_offloadq(unsigned long data)
set_bit(TXQ_RUNNING, &q->flags);
set_bit(TXQ_LAST_PKT_DB, &q->flags);
#endif
+ wmb();
t3_write_reg(adap, A_SG_KDOORBELL,
F_SELEGRCNTX | V_EGRCNTX(q->cntxt_id));
}
@@ -1737,7 +1740,6 @@ static inline int rx_offload(struct t3cdev *tdev, struct sge_rspq *rq,
struct sk_buff *skb, struct sk_buff *rx_gather[],
unsigned int gather_idx)
{
- rq->offload_pkts++;
skb_reset_mac_header(skb);
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
@@ -2031,6 +2033,7 @@ no_mem:
if (eth)
rx_eth(adap, q, skb, ethpad);
else {
+ q->offload_pkts++;
/* Preserve the RSS info in csum & priority */
skb->csum = rss_hi;
skb->priority = rss_lo;
-
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