From: Yunsheng Lin linyunsheng@huawei.com
mainline inclusion from mainline-v5.15-rc7 commit 68752b24f51a category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I4I7P7 CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Currently when there is a rx page allocation failure, it is possible that polling may be stopped if there is no more packet to be reveiced, which may cause queue stall problem under memory pressure.
This patch makes sure polling is scheduled again when there is any rx page allocation failure, and polling will try to allocate receive buffers until it succeeds.
Now the allocation retry is added, it is unnecessary to do the rx page allocation at the end of rx cleaning, so remove it. And reset the unused_count to zero after calling hns3_nic_alloc_rx_buffers() to avoid calling hns3_nic_alloc_rx_buffers() repeatedly under memory pressure.
Fixes: 76ad4f0ee747 ("net: hns3: Add support of HNS3 Ethernet Driver for hip08 SoC") Signed-off-by: Yunsheng Lin linyunsheng@huawei.com Signed-off-by: Guangbin Huang huangguangbin2@huawei.com Signed-off-by: David S. Miller davem@davemloft.net Reviewed-by: Yongxin Li liyongxin1@huawei.com Signed-off-by: Junxin Chen chenjunxin1@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- .../net/ethernet/hisilicon/hns3/hns3_enet.c | 22 ++++++++++--------- 1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c index 655ecc009f77..b2a8abfc4eec 100644 --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -3486,7 +3486,8 @@ static int hns3_desc_unused(struct hns3_enet_ring *ring) return ((ntc >= ntu) ? 0 : ring->desc_num) + ntc - ntu; }
-static void hns3_nic_alloc_rx_buffers(struct hns3_enet_ring *ring, +/* Return true if there is any allocation failure */ +static bool hns3_nic_alloc_rx_buffers(struct hns3_enet_ring *ring, int cleand_count) { struct hns3_desc_cb *desc_cb; @@ -3511,7 +3512,10 @@ static void hns3_nic_alloc_rx_buffers(struct hns3_enet_ring *ring, hns3_rl_err(ring_to_netdev(ring), "alloc rx buffer failed: %d\n", ret); - break; + + writel(i, ring->tqp->io_base + + HNS3_RING_RX_RING_HEAD_REG); + return true; } hns3_replace_buffer(ring, ring->next_to_use, &res_cbs);
@@ -3524,6 +3528,7 @@ static void hns3_nic_alloc_rx_buffers(struct hns3_enet_ring *ring, }
writel(i, ring->tqp->io_base + HNS3_RING_RX_RING_HEAD_REG); + return false; }
static bool hns3_can_reuse_page(struct hns3_desc_cb *cb) @@ -4175,6 +4180,7 @@ int hns3_clean_rx_ring(struct hns3_enet_ring *ring, int budget, { #define RCB_NOF_ALLOC_RX_BUFF_ONCE 16 int unused_count = hns3_desc_unused(ring); + bool failure = false; int recv_pkts = 0; int err;
@@ -4183,9 +4189,9 @@ int hns3_clean_rx_ring(struct hns3_enet_ring *ring, int budget, while (recv_pkts < budget) { /* Reuse or realloc buffers */ if (unused_count >= RCB_NOF_ALLOC_RX_BUFF_ONCE) { - hns3_nic_alloc_rx_buffers(ring, unused_count); - unused_count = hns3_desc_unused(ring) - - ring->pending_buf; + failure = failure || + hns3_nic_alloc_rx_buffers(ring, unused_count); + unused_count = 0; }
/* Poll one pkt */ @@ -4204,11 +4210,7 @@ int hns3_clean_rx_ring(struct hns3_enet_ring *ring, int budget, }
out: - /* Make all data has been write before submit */ - if (unused_count > 0) - hns3_nic_alloc_rx_buffers(ring, unused_count); - - return recv_pkts; + return failure ? budget : recv_pkts; }
static void hns3_update_rx_int_coalesce(struct hns3_enet_tqp_vector *tqp_vector)