From patchwork Tue Jan 11 19:21:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Elder X-Patchwork-Id: 531205 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 945A0C433FE for ; Tue, 11 Jan 2022 19:21:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344610AbiAKTV5 (ORCPT ); Tue, 11 Jan 2022 14:21:57 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41540 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244124AbiAKTV4 (ORCPT ); Tue, 11 Jan 2022 14:21:56 -0500 Received: from mail-il1-x12c.google.com (mail-il1-x12c.google.com [IPv6:2607:f8b0:4864:20::12c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1174CC061751 for ; Tue, 11 Jan 2022 11:21:56 -0800 (PST) Received: by mail-il1-x12c.google.com with SMTP id r16so69468ile.8 for ; Tue, 11 Jan 2022 11:21:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=n01jCl5rCPyfDFPOLy8WiC9NVM2/7mccZVIePFZbu4I=; b=j8vJx99pB1gufpPMx7ta0d9YD6iz9O6WxXvaht+nfwcv8Ri3PwNVv3ppaL73buYw6D bzmPKTBaLCZil3mkXil1e4Ahpi0Q+u+sXyWAVzIxW0Jfe3NdN4eplfwl3pi6hj3ZeI8n RhiY0+KeJ+uREWI50TQxi+4LB/vd6dyRmnR7doJOlawprLG9W3WsWwtFuQcuLyQTkdsi UwYhX4Np6F8YLrf6BSvYile8BC/Blx5nZhSTv620LmJyUxeXHbd1FcS+hZSMYd7aHTut 69AO9BKxfdFmvVhFUZogUanG2PieYLmmQdbvQLTvVVvHVZrbHqKYzbigp27lT9Q3IoY4 uGCA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=n01jCl5rCPyfDFPOLy8WiC9NVM2/7mccZVIePFZbu4I=; b=2hkmOUlnrkxY33JPDKNGfleGK9w7MfUNcXgcnZhvNU6yqBLYobTGnfMk7ohLKKOTEk nAZBnVQ53RlaEhf5C5xnXWYDDbKnIJA/UiNKhqc4rwVryrangPH7hLHP0jK33WOT58Dp ptRC92Tn+cG7a/vOiP2Wd5demWidSjOEeKUSqHW+SJDGszEq2PGvmZIuSW8TKO9SGM2h sVp+y7OocRpmtg3WKa6rXxHfsE1ITigcaCr2OhX2+Bon0F4gcM2nQBmeo/UTISWIpGx8 VumhK9p6C60HM5C1X+O9s2+elnARs/QWtvvxyE9CUu2PFWnT/maP1/NeJlGYa7A1vwXi mWgg== X-Gm-Message-State: AOAM530wcPYFDKiiSphDmrtW2wQS/zoBeK7HNgom6PAcph0JXOCdzl1O BLZ7Ya+cVwx4glr/d3lzlEjmgw== X-Google-Smtp-Source: ABdhPJwsOwzNJBBPPg7cBpEQVQ8jW9K9Mguiw2W8Q7qrcKLw21J2Ai2ozqd/QN9oAZKAZJEgFyfbyw== X-Received: by 2002:a92:c748:: with SMTP id y8mr3075998ilp.140.1641928915449; Tue, 11 Jan 2022 11:21:55 -0800 (PST) Received: from presto.localdomain (c-73-185-129-58.hsd1.mn.comcast.net. [73.185.129.58]) by smtp.gmail.com with ESMTPSA id e17sm6264544iow.30.2022.01.11.11.21.54 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jan 2022 11:21:54 -0800 (PST) From: Alex Elder To: davem@davemloft.net, kuba@kernel.org Cc: jponduru@codeaurora.org, avuyyuru@codeaurora.org, bjorn.andersson@linaro.org, agross@kernel.org, cpratapa@codeaurora.org, subashab@codeaurora.org, evgreen@chromium.org, elder@kernel.org, netdev@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net 1/2] net: ipa: fix atomic update in ipa_endpoint_replenish() Date: Tue, 11 Jan 2022 13:21:49 -0600 Message-Id: <20220111192150.379274-2-elder@linaro.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111192150.379274-1-elder@linaro.org> References: <20220111192150.379274-1-elder@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In ipa_endpoint_replenish(), if an error occurs when attempting to replenish a receive buffer, we just quit and try again later. In that case we increment the backlog count to reflect that the attempt was unsuccessful. Then, if the add_one flag was true we increment the backlog again. This second increment is not included in the backlog local variable though, and its value determines whether delayed work should be scheduled. This is a bug. Fix this by determining whether 1 or 2 should be added to the backlog before adding it in a atomic_add_return() call. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder Reviewed-by: Matthias Kaehlcke --- drivers/net/ipa/ipa_endpoint.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index 49d9a077d0375..8b055885cf3cf 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -1080,6 +1080,7 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, bool add_one) { struct gsi *gsi; u32 backlog; + int delta; if (!endpoint->replenish_enabled) { if (add_one) @@ -1097,10 +1098,8 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, bool add_one) try_again_later: /* The last one didn't succeed, so fix the backlog */ - backlog = atomic_inc_return(&endpoint->replenish_backlog); - - if (add_one) - atomic_inc(&endpoint->replenish_backlog); + delta = add_one ? 2 : 1; + backlog = atomic_add_return(delta, &endpoint->replenish_backlog); /* Whenever a receive buffer transaction completes we'll try to * replenish again. It's unlikely, but if we fail to supply even From patchwork Tue Jan 11 19:21:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alex Elder X-Patchwork-Id: 531614 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55BF2C433FE for ; Tue, 11 Jan 2022 19:22:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346420AbiAKTWA (ORCPT ); Tue, 11 Jan 2022 14:22:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41544 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244426AbiAKTV5 (ORCPT ); Tue, 11 Jan 2022 14:21:57 -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 2F8F6C06173F for ; Tue, 11 Jan 2022 11:21:57 -0800 (PST) Received: by mail-io1-xd2f.google.com with SMTP id o7so230376ioo.9 for ; Tue, 11 Jan 2022 11:21:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=zG6mc9R8T0VuQRaKqR7/UCbKIE1yA2lVDcf9Ztg1BPw=; b=gBRFGEKQyVWTVpOHb0ZBdMzwB0eZcclVsmYYGFXiVzGc7ur6Q/unveTJlSIZDtGNye Bwey6ax7smlPgoxENKvfeUTkXUqsDCnae6KaHOJ+fnmH4iQBKGepbEymAcAWDCi/v2Lv HA1Hxt0IRq3c4TApg664Am2q1WKWazunoH+Io+eaFBgHQZV4tEu0gBC7xAMo3dvVrPvv ftNfkmdZ7MR2hHv6kTugk7ftOl53INz/JHvvnbSUkyNNNswePWt7YZcWirumhuXONycN Cs5ARCOMiIyOmadYZlOWnNPUwTdZ5jqUd6dOgeIgTnRqgiFMxb+yrYTzcswI4y3kuJzo 8j5w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=zG6mc9R8T0VuQRaKqR7/UCbKIE1yA2lVDcf9Ztg1BPw=; b=Bgq6B5TEQVU+bEqGUAhlsucJEpg8CQi/2Sqvi+vjzjT4tzHYdET7NMrTg2IgYfBOSV 2m0w/xywHSrFeGRpYxlLTvBVgURPfuK6BGdLKxvJYH7QB3tBJ9+kIr1sfoxr7wco1qSK 6dLAntrPaGz+FLCf2EIt9ELlAZM6sHzreXmE5ugL6Ng3MUA/hkKIESsZG+63zALorQ0n /GezNDLjwfcFDLzirO+/RYD0NeybhRo0tthk19WRe/DFdaswWGOiHm2l4bgpkenCmgn5 clKD05Oqc4GM5KIxmFPBMeAk29bx9yyjc7DmE5VlUDBqmS7AmjEclEyoA73U3PTnVqf8 tKlg== X-Gm-Message-State: AOAM530DurJRf0zxAodMVQwq26OJRV/SdnZEeVUm9jcfaojNVLV55984 KnlUUGM459W9u4sGSMv3dwa+ug== X-Google-Smtp-Source: ABdhPJwYaKcnyX6qsqEycE/nqRqkIxKSK9nGRQ6obnUE8Pj9wqslbCcNe1OOivkvsJDA+eENKbC+3Q== X-Received: by 2002:a05:6638:1348:: with SMTP id u8mr3068773jad.278.1641928916610; Tue, 11 Jan 2022 11:21:56 -0800 (PST) Received: from presto.localdomain (c-73-185-129-58.hsd1.mn.comcast.net. [73.185.129.58]) by smtp.gmail.com with ESMTPSA id e17sm6264544iow.30.2022.01.11.11.21.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 11 Jan 2022 11:21:56 -0800 (PST) From: Alex Elder To: davem@davemloft.net, kuba@kernel.org Cc: jponduru@codeaurora.org, avuyyuru@codeaurora.org, bjorn.andersson@linaro.org, agross@kernel.org, cpratapa@codeaurora.org, subashab@codeaurora.org, evgreen@chromium.org, elder@kernel.org, netdev@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH net 2/2] net: ipa: prevent concurrent replenish Date: Tue, 11 Jan 2022 13:21:50 -0600 Message-Id: <20220111192150.379274-3-elder@linaro.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220111192150.379274-1-elder@linaro.org> References: <20220111192150.379274-1-elder@linaro.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org We have seen cases where an endpoint RX completion interrupt arrives while replenishing for the endpoint is underway. This causes another instance of replenishing to begin as part of completing the receive transaction. If this occurs it can lead to transaction corruption. Use a new atomic variable to ensure only replenish instance for an endpoint executes at a time. Fixes: 84f9bd12d46db ("soc: qcom: ipa: IPA endpoints") Signed-off-by: Alex Elder --- drivers/net/ipa/ipa_endpoint.c | 13 +++++++++++++ drivers/net/ipa/ipa_endpoint.h | 2 ++ 2 files changed, 15 insertions(+) diff --git a/drivers/net/ipa/ipa_endpoint.c b/drivers/net/ipa/ipa_endpoint.c index 8b055885cf3cf..a1019f5fe1748 100644 --- a/drivers/net/ipa/ipa_endpoint.c +++ b/drivers/net/ipa/ipa_endpoint.c @@ -1088,15 +1088,27 @@ static void ipa_endpoint_replenish(struct ipa_endpoint *endpoint, bool add_one) return; } + /* If already active, just update the backlog */ + if (atomic_xchg(&endpoint->replenish_active, 1)) { + if (add_one) + atomic_inc(&endpoint->replenish_backlog); + return; + } + while (atomic_dec_not_zero(&endpoint->replenish_backlog)) if (ipa_endpoint_replenish_one(endpoint)) goto try_again_later; + + atomic_set(&endpoint->replenish_active, 0); + if (add_one) atomic_inc(&endpoint->replenish_backlog); return; try_again_later: + atomic_set(&endpoint->replenish_active, 0); + /* The last one didn't succeed, so fix the backlog */ delta = add_one ? 2 : 1; backlog = atomic_add_return(delta, &endpoint->replenish_backlog); @@ -1691,6 +1703,7 @@ static void ipa_endpoint_setup_one(struct ipa_endpoint *endpoint) * backlog is the same as the maximum outstanding TREs. */ endpoint->replenish_enabled = false; + atomic_set(&endpoint->replenish_active, 0); atomic_set(&endpoint->replenish_saved, gsi_channel_tre_max(gsi, endpoint->channel_id)); atomic_set(&endpoint->replenish_backlog, 0); diff --git a/drivers/net/ipa/ipa_endpoint.h b/drivers/net/ipa/ipa_endpoint.h index 0a859d10312dc..200f093214997 100644 --- a/drivers/net/ipa/ipa_endpoint.h +++ b/drivers/net/ipa/ipa_endpoint.h @@ -53,6 +53,7 @@ enum ipa_endpoint_name { * @netdev: Network device pointer, if endpoint uses one * @replenish_enabled: Whether receive buffer replenishing is enabled * @replenish_ready: Number of replenish transactions without doorbell + * @replenish_active: 1 when replenishing is active, 0 otherwise * @replenish_saved: Replenish requests held while disabled * @replenish_backlog: Number of buffers needed to fill hardware queue * @replenish_work: Work item used for repeated replenish failures @@ -74,6 +75,7 @@ struct ipa_endpoint { /* Receive buffer replenishing for RX endpoints */ bool replenish_enabled; u32 replenish_ready; + atomic_t replenish_active; atomic_t replenish_saved; atomic_t replenish_backlog; struct delayed_work replenish_work; /* global wq */