From patchwork Mon Aug 16 04:05:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bongsu Jeon X-Patchwork-Id: 497797 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 9FEF5C4320E for ; Mon, 16 Aug 2021 04:06:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 86A9D613D0 for ; Mon, 16 Aug 2021 04:06:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232739AbhHPEHH (ORCPT ); Mon, 16 Aug 2021 00:07:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34706 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230257AbhHPEGs (ORCPT ); Mon, 16 Aug 2021 00:06:48 -0400 Received: from mail-pj1-x1035.google.com (mail-pj1-x1035.google.com [IPv6:2607:f8b0:4864:20::1035]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0F3EEC0613CF; Sun, 15 Aug 2021 21:06:18 -0700 (PDT) Received: by mail-pj1-x1035.google.com with SMTP id n13-20020a17090a4e0d00b0017946980d8dso11358710pjh.5; Sun, 15 Aug 2021 21:06:18 -0700 (PDT) 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=SRoGE6btz3FIzsoVU86GKd+sAIx4GipMBZ33HNO90os=; b=Pd9zk65/+kFF5GDGVDxQwpyZalbA3joiA6kVand7R7RU1uHhpsD7kaIuM3PCgxyhrz ooaT6q6u5i9zGkFo9PzovH1yiH3Mz0VXKar50oo/FkZanUZYZjfgWqD5qb+MdIm55O7m sSWJBHvftQ8oOjkF6g0+h6Ft0XmesX6jgxvyFYOXYkQYdav2SrMu6b1TfePXtoD53T5Y kkub9/FAtGHPp0h/6P6CA5zv1Sl+86MI4yJDpE+8TpuWfBh6V9x0KVMKA5/mhG31YYp1 v5L5FjvnOBFEPOQ3oZl1kqDT9ex0cPn0W0P3rYvCx4kws6/rASYIBZDmiUoE+B1Sl9ao gV6g== 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=SRoGE6btz3FIzsoVU86GKd+sAIx4GipMBZ33HNO90os=; b=bJkL5DrgGpZKlEKbZgSY+m8PFCvQkETfzTfw7pTFUIXHqUkKC8IwWGkwMGBpHwy48V O62oWoaWBPL06pT+a7JtuLS3ueCGm4Zrkz68T6iZg59Ggx0Q0gy7i63iBNG51P7ZHfCt voI9H+9dMwKqvN50xD74gu5DlmbA7Uk/TpWyx3ONH7YdBQYL4zLBM7SoBkkzsTtDMI/C 3MOLUS1geac0j/Zfo9qLBDhuEjlbRbBN1I9acmHLo6jRTJ3YDuovvILZemB8rWtj9WLM NUiKKabBLUcYxVQkQ6SHClqYusXFkPYRWkG8pNSeTqSyXxT/LXzfvlp22j5PUGgHoMdB zn1A== X-Gm-Message-State: AOAM530muIVpU5AV5CKKKMOtb8te9kXJr3tST9oSdhKCBCkVChjC9hZg /xEC5b6VFfwpgrTmbEdFmzA= X-Google-Smtp-Source: ABdhPJyOUpYN9GoJC+C8C2qZrzfUkPYDKbU61b/QtSTN8i0QTo860aLD7Xxl6TNxxcvcZOFhVaGZIg== X-Received: by 2002:a17:90a:35e:: with SMTP id 30mr15452139pjf.160.1629086777396; Sun, 15 Aug 2021 21:06:17 -0700 (PDT) Received: from ubuntu.localdomain ([182.226.226.37]) by smtp.gmail.com with ESMTPSA id i6sm9436998pfa.44.2021.08.15.21.06.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 15 Aug 2021 21:06:16 -0700 (PDT) From: bongsu.jeon2@gmail.com To: shuah@kernel.org, krzysztof.kozlowski@canonical.com Cc: netdev@vger.kernel.org, linux-nfc@lists.01.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, Bongsu Jeon Subject: [PATCH net-next 1/3] nfc: Change the virtual NCI device driver to use Wait Queue Date: Sun, 15 Aug 2021 21:05:58 -0700 Message-Id: <20210816040600.175813-2-bongsu.jeon2@gmail.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210816040600.175813-1-bongsu.jeon2@gmail.com> References: <20210816040600.175813-1-bongsu.jeon2@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Bongsu Jeon In previous version, the user level virtual device application that used this driver should have the polling scheme to read a NCI frame. To remove this polling scheme, changed the driver code to use Wait Queue. Signed-off-by: Bongsu Jeon --- drivers/nfc/virtual_ncidev.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/nfc/virtual_ncidev.c b/drivers/nfc/virtual_ncidev.c index 2ee0ec4bb739..1953904176a2 100644 --- a/drivers/nfc/virtual_ncidev.c +++ b/drivers/nfc/virtual_ncidev.c @@ -10,6 +10,7 @@ #include #include #include +#include #include enum virtual_ncidev_mode { @@ -27,6 +28,7 @@ enum virtual_ncidev_mode { NFC_PROTO_ISO15693_MASK) static enum virtual_ncidev_mode state; +static DECLARE_WAIT_QUEUE_HEAD(wq); static struct miscdevice miscdev; static struct sk_buff *send_buff; static struct nci_dev *ndev; @@ -61,6 +63,7 @@ static int virtual_nci_send(struct nci_dev *ndev, struct sk_buff *skb) } send_buff = skb_copy(skb, GFP_KERNEL); mutex_unlock(&nci_mutex); + wake_up_interruptible(&wq); return 0; } @@ -76,12 +79,11 @@ static ssize_t virtual_ncidev_read(struct file *file, char __user *buf, { size_t actual_len; - mutex_lock(&nci_mutex); - if (!send_buff) { - mutex_unlock(&nci_mutex); + wait_event_interruptible(wq, send_buff); + if (!send_buff) return 0; - } + mutex_lock(&nci_mutex); actual_len = min_t(size_t, count, send_buff->len); if (copy_to_user(buf, send_buff->data, actual_len)) {