From patchwork Wed Feb 1 14:26:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sergey Organov X-Patchwork-Id: 649606 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 BB5ECC05027 for ; Wed, 1 Feb 2023 14:27:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231923AbjBAO1z (ORCPT ); Wed, 1 Feb 2023 09:27:55 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39754 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232094AbjBAO1s (ORCPT ); Wed, 1 Feb 2023 09:27:48 -0500 Received: from mail-ed1-x534.google.com (mail-ed1-x534.google.com [IPv6:2a00:1450:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E58182CFD9 for ; Wed, 1 Feb 2023 06:27:45 -0800 (PST) Received: by mail-ed1-x534.google.com with SMTP id cw4so12728234edb.13 for ; Wed, 01 Feb 2023 06:27:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=WEm5A99uTG2c238a+JDBkz/mOTpdwi/bBFV9FIiWCUw=; b=hqqEqTK0vARzjhmqa9hC6bsI/43ShQLK8//yNN4LKLiy2WkIGvyXDYZ2m8GwRYhND9 bDzPhj4P3JTMuOHV7ReCUIXnc+k2DCtkuR5WATi1e7simYqn/scDIwWxlbFDqU4KBPXa eZE33vSPuG4gKrpDbQf+ma7fIakaRy+/RXJ2rEjomknemkaxN2HKc5nAxtz5XIpuaRfe puxzpZUI8J04cDtaG4LZIeabkjgsApoH4KDJtMnW1DwWjeFb9Hm/LTHGGmNzxV//ZyrK HMNT3e/PUk/YtM9L+ZlZ5mRx45dDZ0cIiRwiQFQ6YUfQTutjE7IRwN5dxXFb9HS44Xh/ L0pA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=WEm5A99uTG2c238a+JDBkz/mOTpdwi/bBFV9FIiWCUw=; b=vSjJ4jvaruGwJGheJtCT2Wogo6XKdWHFYt0nLK9yH4OhHE4V1ZvxEvvPXOzBWOkXac ZhuiIu/Oe3F4eOj6eQSYlBfCmAU6HvcwlVFU5nU+yi3T3X6G5nYAX2tK1xYLaqouAUha kdvKR9JOsc6/qQkZ5REuVMcs3JcPcA8EhUxM1G6MB37dQRJ+dscIqPS191cmpMI3yvaz Pf4CJHdhSFt2zfktdZfaiyWS/leskFalE7hWKf08WK9uTk5Spx0v/Y2+tMPtj0UQwhQm s9MaTl7Njz6PVOk5mkjSEeBL/D60Y9bvVlcR5eahieHLAFys4q0nl1N0kRj7RTCHwPe0 bgWw== X-Gm-Message-State: AO0yUKU7GIT8C2Dk5dqdKRoJlOTETSe0C4NKpTdRtRQ0+996nM6zsAcc g2/lEPuG+iWelZr5DmcfX38= X-Google-Smtp-Source: AK7set8ws7NdcXePeM55LM4BT1j7mYwM+w20CWy2QWuufVGR25bLp8ZxOOgYCX5HpeGK6TKSRutHlA== X-Received: by 2002:aa7:de13:0:b0:499:d0e3:7745 with SMTP id h19-20020aa7de13000000b00499d0e37745mr2245544edv.14.1675261664352; Wed, 01 Feb 2023 06:27:44 -0800 (PST) Received: from osv.localdomain ([89.175.180.246]) by smtp.gmail.com with ESMTPSA id cf8-20020a0564020b8800b004a18f2ffb86sm8975564edb.79.2023.02.01.06.27.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Feb 2023 06:27:43 -0800 (PST) From: Sergey Organov To: Greg Kroah-Hartman Cc: linux-serial@vger.kernel.org, Fabio Estevam , Jiri Slaby , Richard Genoud , Sascha Hauer , Shawn Guo , Tim Harvey , =?utf-8?q?Tomasz_Mo=C5=84?= , =?utf-8?q?Uwe_Kle?= =?utf-8?q?ine-K=C3=B6nig?= , Johan Hovold , =?utf-8?q?Ilpo_J=C3=A4rvinen?= , Sherry Sun , Stefan Wahren , linux-arm-kernel@lists.infradead.org, NXP Linux Team , Pengutronix Kernel Team , Sergey Organov Subject: [PATCH v1 4/7] serial: imx: do not break from FIFO reading loop prematurely Date: Wed, 1 Feb 2023 17:26:57 +0300 Message-Id: <20230201142700.4346-5-sorganov@gmail.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230201142700.4346-1-sorganov@gmail.com> References: <87bko4e65y.fsf@osv.gnss.ru> <20230201142700.4346-1-sorganov@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org There is no reason to prematurely break out of FIFO reading loop, and it might cause needless reenters into ISR, so keep reading until FIFO is empty. Signed-off-by: Sergey Organov --- drivers/tty/serial/imx.c | 10 +++------- 1 file changed, 3 insertions(+), 7 deletions(-) diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c index e709118fe85c..797c441088a9 100644 --- a/drivers/tty/serial/imx.c +++ b/drivers/tty/serial/imx.c @@ -888,7 +888,7 @@ static void imx_uart_check_flood(struct imx_port *sport, u32 usr2) static irqreturn_t __imx_uart_rxint(int irq, void *dev_id) { struct imx_port *sport = dev_id; - unsigned int rx, flg, ignored = 0; + unsigned int rx, flg; struct tty_port *port = &sport->port.state->port; u32 usr2; @@ -921,11 +921,8 @@ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id) if (rx & URXD_OVRRUN) sport->port.icount.overrun++; - if (rx & sport->port.ignore_status_mask) { - if (++ignored > 100) - goto out; + if (rx & sport->port.ignore_status_mask) continue; - } rx &= (sport->port.read_status_mask | 0xFF); @@ -944,13 +941,12 @@ static irqreturn_t __imx_uart_rxint(int irq, void *dev_id) } if (sport->port.ignore_status_mask & URXD_DUMMY_READ) - goto out; + continue; if (tty_insert_flip_char(port, rx, flg) == 0) sport->port.icount.buf_overrun++; } -out: tty_flip_buffer_push(port); return IRQ_HANDLED;