From: Sven Van Asbroeck <[email protected]> Simulate low-memory in lan743x_rx_allocate_skb(): fail 10 allocations in a row in every 100.
Signed-off-by: Sven Van Asbroeck <[email protected]> --- Tree: git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git # 46eb3c108fe1 To: Bryan Whitehead <[email protected]> To: [email protected] To: "David S. Miller" <[email protected]> To: Jakub Kicinski <[email protected]> Cc: Andrew Lunn <[email protected]> Cc: Alexey Denisov <[email protected]> Cc: Sergej Bauer <[email protected]> Cc: Tim Harvey <[email protected]> Cc: Anders Rønningen <[email protected]> Cc: [email protected] Cc: [email protected] (open list) 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 ed4959ad9237..149b482fd984 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, length, GFP_ATOMIC | GFP_DMA); + skb = lan743x_alloc_skb(netdev, length, can_fail); if (!skb) return -ENOMEM; dma_ptr = dma_map_single(dev, skb->data, length, DMA_FROM_DEVICE); @@ -2130,7 +2143,7 @@ static int lan743x_rx_process_packet(struct lan743x_rx *rx) skb = buffer_info->skb; /* allocate new skb and map to dma */ - 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. @@ -2330,7 +2343,7 @@ 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
