From patchwork Thu Feb 11 16:18:29 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Sven Van Asbroeck X-Patchwork-Id: 382321 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, 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 9EDB6C433E0 for ; Thu, 11 Feb 2021 16:22:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4077B64E92 for ; Thu, 11 Feb 2021 16:22:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231858AbhBKQWX (ORCPT ); Thu, 11 Feb 2021 11:22:23 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231857AbhBKQTb (ORCPT ); Thu, 11 Feb 2021 11:19:31 -0500 Received: from mail-io1-xd2f.google.com (mail-io1-xd2f.google.com [IPv6:2607:f8b0:4864:20::d2f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C64FC0617A7; Thu, 11 Feb 2021 08:18:40 -0800 (PST) Received: by mail-io1-xd2f.google.com with SMTP id u8so6209631ior.13; Thu, 11 Feb 2021 08:18:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=n9Lhs45v53vKs8blqT5xx3avh0Ky4AFVSwRqrogf4Kc=; b=QjgIxtA4Y8mhJo/VAl/qdtaXPMK1H4QqSEx/YPmco/Z4H0okgU6lXaSona8jWzYyRb lwksMVAhj92wSO8wkBqc8l8tRIoCTgGLzDLX9nM2+9cBGvR7y4e0fdJIPubtIBhbWQ0J VxQnN469xBCne+EAjgk2wTwCfFZsXGlDxZA6UoBtR8T+JRGXCstKpbdFwb/6X4EW8ccx Ub+qZChiZr9qytPhO7X2ITT8WJlUuEuqwPDbEtU6wuGQh6qHxDu5ZVOWw1jCjMGcksYT MGZgNyTqlLWy2Vhj1mwmjHF19CnfQxku/EhUcRxAl+FX1myupTO/+v5GL2OHS0ae4ieG jLIw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=n9Lhs45v53vKs8blqT5xx3avh0Ky4AFVSwRqrogf4Kc=; b=G94NaEfkbYfQc8eesVPQCpxFVg9msE/5/AWj0FBZxHMZtotYeSzbBh/+TggCqYYwuy C79SrN+TYvF8dNZsvxmqrnF1hANci2saNqAmfAHHhVucmjrepUM+pK0D13w9dnGRZhkM YLdsHsDHsbJahvzWW4TyPwwFViqGqUSpSZrKYbkc5CD7sDraRDTVXFH00FJxscgRmG29 JvRaVbRhw7Zr2STVneDp+mCslEAd/d+JAl50D5l0kzHIO2tNWwxm4ihz0A9EaD9hB5Ln soP4GAbYp+2P1a1yUrJcWFhIMZykEXnpkgd0odDZfQ4/N5ISEIwv8HGX2xlpju+y/K5J NJhQ== X-Gm-Message-State: AOAM531rAO0BvYh/3OEN7xtYg1MXYrF3S4tL1RQE1VuOSqD6zqRGTsvg rs3eJsRJolhFMMZzjehOiz4= X-Google-Smtp-Source: ABdhPJwDwAcCh8k+TeG2+JSo9wEcbcl6UCYhwtkL2cOwP/izDt8c0Odwx6rKjeaTrJ3xoHyl0+BsWA== X-Received: by 2002:a05:6602:24c4:: with SMTP id h4mr6265993ioe.7.1613060319554; Thu, 11 Feb 2021 08:18:39 -0800 (PST) Received: from localhost.localdomain ([198.52.185.246]) by smtp.gmail.com with ESMTPSA id d135sm2729913iog.35.2021.02.11.08.18.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 11 Feb 2021 08:18:39 -0800 (PST) From: Sven Van Asbroeck X-Google-Original-From: Sven Van Asbroeck To: Bryan Whitehead , UNGLinuxDriver@microchip.com, David S Miller , Jakub Kicinski Cc: Sven Van Asbroeck , Andrew Lunn , Alexey Denisov , Sergej Bauer , Tim Harvey , =?utf-8?q?Anders_R=C3=B8nn?= =?utf-8?q?ingen?= , Hillf Danton , Christoph Hellwig , Willem de Bruijn , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net-next v2 4/5] TEST ONLY: lan743x: skb_alloc failure test Date: Thu, 11 Feb 2021 11:18:29 -0500 Message-Id: <20210211161830.17366-5-TheSven73@gmail.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210211161830.17366-1-TheSven73@gmail.com> References: <20210211161830.17366-1-TheSven73@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Sven Van Asbroeck Simulate low-memory in lan743x_rx_allocate_skb(): fail 10 allocations in a row in every 100. Signed-off-by: Sven Van Asbroeck --- To: Bryan Whitehead To: UNGLinuxDriver@microchip.com To: "David S. Miller" To: Jakub Kicinski Cc: Andrew Lunn Cc: Alexey Denisov Cc: Sergej Bauer Cc: Tim Harvey Cc: Anders Rønningen Cc: Hillf Danton Cc: Christoph Hellwig Cc: Willem de Bruijn Cc: netdev@vger.kernel.org Cc: linux-kernel@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; }