From: Sven Van Asbroeck <thesve...@gmail.com>
Simulate low-memory in lan743x_rx_allocate_skb(): fail 10
allocations in a row in every 100.
Signed-off-by: Sven Van Asbroeck <thesve...@gmail.com>
---
To: Bryan Whitehead <bryan.whiteh...@microchip.com>
To: unglinuxdri...@microchip.com
To: "David S. Miller" <da...@davemloft.net>
To: Jakub Kicinski <k...@kernel.org>
Cc: Andrew Lunn <and...@lunn.ch>
Cc: Alexey Denisov <rtg...@gmail.com>
Cc: Sergej Bauer <sba...@blackbox.su>
Cc: Tim Harvey <thar...@gateworks.com>
Cc: Anders Rønningen <and...@ronningen.priv.no>
Cc: Hillf Danton <hdan...@sina.com>
Cc: Christoph Hellwig <h...@lst.de>
Cc: Willem de Bruijn <willemdebruijn.ker...@gmail.com>
Cc: netdev@vger.kernel.org
Cc: linux-ker...@vger.kernel.org
drivers/net/ethernet/microchip/lan743x_main.c | 21 +++++++++++++++----
1 file changed, 17 insertions(+), 4 deletions(-)
diff --git a/drivers/net/ethernet/microchip/lan743x_main.c
b/drivers/net/ethernet/microchip/lan743x_main.c
index 90d49231494d..0094ecac5741 100644
--- a/drivers/net/ethernet/microchip/lan743x_main.c
+++ b/drivers/net/ethernet/microchip/lan743x_main.c
@@ -1963,7 +1963,20 @@ static void lan743x_rx_update_tail(struct lan743x_rx
*rx, int index)
index);
}
-static int lan743x_rx_init_ring_element(struct lan743x_rx *rx, int index)
+static struct sk_buff *
+lan743x_alloc_skb(struct net_device *netdev, int length, bool can_fail)
+{
+ static int rx_alloc;
+ int counter = rx_alloc++ % 100;
+
+ if (can_fail && counter >= 20 && counter < 30)
+ return NULL;
+
+ return __netdev_alloc_skb(netdev, length, GFP_ATOMIC | GFP_DMA);
+}
+
+static int
+lan743x_rx_init_ring_element(struct lan743x_rx *rx, int index, bool can_fail)
{
struct net_device *netdev = rx->adapter->netdev;
struct device *dev = &rx->adapter->pdev->dev;
@@ -1977,7 +1990,7 @@ static int lan743x_rx_init_ring_element(struct lan743x_rx
*rx, int index)
descriptor = &rx->ring_cpu_ptr[index];
buffer_info = &rx->buffer_info[index];
- skb = __netdev_alloc_skb(netdev, buffer_length, GFP_ATOMIC | GFP_DMA);
+ skb = lan743x_alloc_skb(netdev, buffer_length, can_fail);
if (!skb)
return -ENOMEM;
dma_ptr = dma_map_single(dev, skb->data, buffer_length,
DMA_FROM_DEVICE);
@@ -2137,7 +2150,7 @@ static int lan743x_rx_process_buffer(struct lan743x_rx
*rx)
/* save existing skb, allocate new skb and map to dma */
skb = buffer_info->skb;
- if (lan743x_rx_init_ring_element(rx, rx->last_head)) {
+ if (lan743x_rx_init_ring_element(rx, rx->last_head, true)) {
/* failed to allocate next skb.
* Memory is very low.
* Drop this packet and reuse buffer.
@@ -2342,7 +2355,7 @@ static int lan743x_rx_ring_init(struct lan743x_rx *rx)
rx->last_head = 0;
for (index = 0; index < rx->ring_size; index++) {
- ret = lan743x_rx_init_ring_element(rx, index);
+ ret = lan743x_rx_init_ring_element(rx, index, false);
if (ret)
goto cleanup;
}
--
2.17.1
