netdev: octeon_mgmt: Fix race condition freeing TX buffers.
Under heavy load the TX cleanup tasklet and xmit threads would race
and try to free too many buffers.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/octeon/octeon_mgmt.c b/drivers/net/octeon/octeon_mgmt.c
index bbbd737..b975a2f 100644
--- a/drivers/net/octeon/octeon_mgmt.c
+++ b/drivers/net/octeon/octeon_mgmt.c
@@ -189,12 +189,19 @@
mix_orcnt.u64 = cvmx_read_csr(CVMX_MIXX_ORCNT(port));
while (mix_orcnt.s.orcnt) {
+ spin_lock_irqsave(&p->tx_list.lock, flags);
+
+ mix_orcnt.u64 = cvmx_read_csr(CVMX_MIXX_ORCNT(port));
+
+ if (mix_orcnt.s.orcnt == 0) {
+ spin_unlock_irqrestore(&p->tx_list.lock, flags);
+ break;
+ }
+
dma_sync_single_for_cpu(p->dev, p->tx_ring_handle,
ring_size_to_bytes(OCTEON_MGMT_TX_RING_SIZE),
DMA_BIDIRECTIONAL);
- spin_lock_irqsave(&p->tx_list.lock, flags);
-
re.d64 = p->tx_ring[p->tx_next_clean];
p->tx_next_clean =
(p->tx_next_clean + 1) % OCTEON_MGMT_TX_RING_SIZE;