From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 2CB65C33CB1 for ; Thu, 16 Jan 2020 07:45:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F12912075B for ; Thu, 16 Jan 2020 07:45:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729369AbgAPHpQ (ORCPT ); Thu, 16 Jan 2020 02:45:16 -0500 Received: from szxga05-in.huawei.com ([45.249.212.191]:8742 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726653AbgAPHpP (ORCPT ); Thu, 16 Jan 2020 02:45:15 -0500 Received: from DGGEMS407-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id A64F24145302815F6FFA; Thu, 16 Jan 2020 15:45:13 +0800 (CST) Received: from localhost.localdomain (10.67.165.24) by DGGEMS407-HUB.china.huawei.com (10.3.19.207) with Microsoft SMTP Server id 14.3.439.0; Thu, 16 Jan 2020 15:45:03 +0800 From: Yonglong Liu To: CC: , , , , Subject: [PATCH net] net: hns: fix soft lockup when there is not enough memory Date: Thu, 16 Jan 2020 15:41:17 +0800 Message-ID: <1579160477-31030-1-git-send-email-liuyonglong@huawei.com> X-Mailer: git-send-email 2.8.1 MIME-Version: 1.0 Content-Type: text/plain X-Originating-IP: [10.67.165.24] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When there is not enough memory and napi_alloc_skb() return NULL, the HNS driver will print error message, and than try again, if the memory is not enough for a while, huge error message and the retry operation will cause soft lockup. When napi_alloc_skb() return NULL because of no memory, we can get a warn_alloc() call trace, so this patch deletes the error message. We already use polling mode to handle irq, but the retry operation will render the polling weight inactive, this patch just return budget when the rx is not completed to avoid dead loop. Fixes: 36eedfde1a36 ("net: hns: Optimize hns_nic_common_poll for better performance") Fixes: b5996f11ea54 ("net: add Hisilicon Network Subsystem basic ethernet support") Signed-off-by: Yonglong Liu --- drivers/net/ethernet/hisilicon/hns/hns_enet.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/net/ethernet/hisilicon/hns/hns_enet.c b/drivers/net/ethernet/hisilicon/hns/hns_enet.c index 14ab204..eb69e5c 100644 --- a/drivers/net/ethernet/hisilicon/hns/hns_enet.c +++ b/drivers/net/ethernet/hisilicon/hns/hns_enet.c @@ -565,7 +565,6 @@ static int hns_nic_poll_rx_skb(struct hns_nic_ring_data *ring_data, skb = *out_skb = napi_alloc_skb(&ring_data->napi, HNS_RX_HEAD_SIZE); if (unlikely(!skb)) { - netdev_err(ndev, "alloc rx skb fail\n"); ring->stats.sw_err_cnt++; return -ENOMEM; } @@ -1056,7 +1055,6 @@ static int hns_nic_common_poll(struct napi_struct *napi, int budget) container_of(napi, struct hns_nic_ring_data, napi); struct hnae_ring *ring = ring_data->ring; -try_again: clean_complete += ring_data->poll_one( ring_data, budget - clean_complete, ring_data->ex_process); @@ -1066,7 +1064,7 @@ static int hns_nic_common_poll(struct napi_struct *napi, int budget) napi_complete(napi); ring->q->handle->dev->ops->toggle_ring_irq(ring, 0); } else { - goto try_again; + return budget; } } -- 2.8.1