From patchwork Wed Apr 21 09:54:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Johan Hovold X-Patchwork-Id: 425681 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=-19.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, 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 44F57C4361A for ; Wed, 21 Apr 2021 09:55:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 090A261449 for ; Wed, 21 Apr 2021 09:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238761AbhDUJ4S (ORCPT ); Wed, 21 Apr 2021 05:56:18 -0400 Received: from mail.kernel.org ([198.145.29.99]:52570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238620AbhDUJ4K (ORCPT ); Wed, 21 Apr 2021 05:56:10 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id A6E206145B; Wed, 21 Apr 2021 09:55:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1618998936; bh=rpTrUwy38tMF4LXHWp5J+Jv1V+4HlHiORTormNkoodU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lvWf0IoKfhZ+hNZQ24jntnjzzoOv1G8xte4bMStk7WAmXLPCb1DUIEXzAOZizz7Xf HVeofCpUtWdDiyYjhJP1hCYhx0a6ncoXIcLMof4XT3s6aCEkmcsUShg1BUY9Q1XH5M cx12uy7NX5R9d3cnrdlTRVm5gdbjy4KgGJZIp16FLE/XuKc4fshO8nTBJTLkXVxX4O w6hu7yLNCiLyd0Ax4AW4KjJIg7WPxKbMHUUR34h7lpMB5gXCzDP0CdQh2N4J0rCJ8L HexyA08lOb/K+w3K0qJC2bu+XJx9uhy9nh2jXGTMyhs1fl8uuuM4abLXemSdtMwgJb o1O89ga9ZjXRw== Received: from johan by xi.lan with local (Exim 4.93.0.4) (envelope-from ) id 1lZ9a8-0000p3-0B; Wed, 21 Apr 2021 11:55:40 +0200 From: Johan Hovold To: Greg Kroah-Hartman Cc: Jiri Slaby , linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org, Johan Hovold Subject: [PATCH 15/26] serial: mpc52xx_uart: drop low-latency workaround Date: Wed, 21 Apr 2021 11:54:58 +0200 Message-Id: <20210421095509.3024-16-johan@kernel.org> X-Mailer: git-send-email 2.26.3 In-Reply-To: <20210421095509.3024-1-johan@kernel.org> References: <20210421095509.3024-1-johan@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org Commit fbe543b412ce ("Fix a potential issue in mpc52xx uart driver") worked around the infamous low_latency behaviour of tty_flip_buffer_push() by simply dropping and reacquiring the port lock in the interrupt handler. Since commit a9c3f68f3cd8 ("tty: Fix low_latency BUG"), tty_flip_buffer_push() always schedules a work item to push data to the line discipline and there's no need to keep any low_latency hacks around. Signed-off-by: Johan Hovold --- drivers/tty/serial/mpc52xx_uart.c | 2 -- 1 file changed, 2 deletions(-) diff --git a/drivers/tty/serial/mpc52xx_uart.c b/drivers/tty/serial/mpc52xx_uart.c index af1700445251..2704dc988e4a 100644 --- a/drivers/tty/serial/mpc52xx_uart.c +++ b/drivers/tty/serial/mpc52xx_uart.c @@ -1421,9 +1421,7 @@ mpc52xx_uart_int_rx_chars(struct uart_port *port) } } - spin_unlock(&port->lock); tty_flip_buffer_push(tport); - spin_lock(&port->lock); return psc_ops->raw_rx_rdy(port); }