From mboxrd@z Thu Jan 1 00:00:00 1970 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 C48AFC433EF for ; Thu, 3 Feb 2022 08:37:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349503AbiBCIhA (ORCPT ); Thu, 3 Feb 2022 03:37:00 -0500 Received: from mail-ej1-f43.google.com ([209.85.218.43]:43626 "EHLO mail-ej1-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235967AbiBCIg6 (ORCPT ); Thu, 3 Feb 2022 03:36:58 -0500 Received: by mail-ej1-f43.google.com with SMTP id d10so6207784eje.10 for ; Thu, 03 Feb 2022 00:36:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:message-id:date:mime-version:user-agent:subject :content-language:to:references:from:in-reply-to :content-transfer-encoding; bh=rST6XoS1u5VzZxuiTsE/1QU7kaonjAW+wgoRJl2TR6U=; b=Aow1bysBhxsa0Vu8IvCCXgsqfVt2r2PQ9j2rNct+RfCJRYSv9CkNzga7nqNI2rkpo3 TOl5tsFPwkDFO4eIu2u8rM8LmFRkeSaO6LZdrfiLh0D5jdcAcYMCcjtXazIWZ5Uq2PD+ HLMIiYsa3oN8MG5CuS0JdACxT4qEw8d6SQHHKEkJqq/3ABtjQUSfmd2Vww2XNJLeIGXc Dm52oj3f+leYOnJmwMuTcqoJe62B+midEXf6U7b8HaVtcDos21jifta/w3KSvXcAOYGC Z1hFnkvpfvbaeSVv74oTy9vzLZEortQKosF7SLte6Y1t2q+Y6QUt1A3exdAmVeG38jFl bZUQ== X-Gm-Message-State: AOAM533TSk2symfGt+4ae4Wbc7nrXN+7OsqO0kBBT0x6AfK6E2AezyZ0 pQnW11HKcwUCXlq23wpTQCnQKYaC4+U= X-Google-Smtp-Source: ABdhPJw8WkVKaUmDwMBpPGJf+l+UkfYFE9ZLGalO/Mqir6cDzU/qaJZjacUk63kbsVD/jICvfkS7Sg== X-Received: by 2002:a17:907:6d83:: with SMTP id sb3mr28985595ejc.21.1643877416997; Thu, 03 Feb 2022 00:36:56 -0800 (PST) Received: from ?IPV6:2a0b:e7c0:0:107::70f? ([2a0b:e7c0:0:107::70f]) by smtp.gmail.com with ESMTPSA id i12sm16180535ejy.43.2022.02.03.00.36.56 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 03 Feb 2022 00:36:56 -0800 (PST) Message-ID: <37e31d03-eee6-7052-fe32-1f37f1b460e1@kernel.org> Date: Thu, 3 Feb 2022 09:36:55 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.5.0 Subject: Re: [PATCH v1 1/1] tty: Drop duplicate NULL check in TTY port functions Content-Language: en-US To: Andy Shevchenko , Greg Kroah-Hartman , linux-kernel@vger.kernel.org References: <20220202165704.5680-1-andriy.shevchenko@linux.intel.com> From: Jiri Slaby In-Reply-To: <20220202165704.5680-1-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02. 02. 22, 17:57, Andy Shevchenko wrote: > The free_page(addr), which becomes free_pages(addr, 0) checks addr against 0. > No need to repeat this check in the callers, i.e. tty_port_free_xmit_buf() > and tty_port_destructor(). > > Note, INIT_KFIFO() is safe without that check, because it's aware of kfifo PTR > versus embedded kfifo. Not sure what you mean here ^^^? But it might be one of the morning brain parser errors. Acked-by: Jiri Slaby > Signed-off-by: Andy Shevchenko > --- > drivers/tty/tty_port.c | 11 ++++------- > 1 file changed, 4 insertions(+), 7 deletions(-) > > diff --git a/drivers/tty/tty_port.c b/drivers/tty/tty_port.c > index 4282895ede9e..880608a65773 100644 > --- a/drivers/tty/tty_port.c > +++ b/drivers/tty/tty_port.c > @@ -240,11 +240,9 @@ EXPORT_SYMBOL(tty_port_alloc_xmit_buf); > void tty_port_free_xmit_buf(struct tty_port *port) > { > mutex_lock(&port->buf_mutex); > - if (port->xmit_buf != NULL) { > - free_page((unsigned long)port->xmit_buf); > - port->xmit_buf = NULL; > - INIT_KFIFO(port->xmit_fifo); > - } > + free_page((unsigned long)port->xmit_buf); > + port->xmit_buf = NULL; > + INIT_KFIFO(port->xmit_fifo); > mutex_unlock(&port->buf_mutex); > } > EXPORT_SYMBOL(tty_port_free_xmit_buf); > @@ -271,8 +269,7 @@ static void tty_port_destructor(struct kref *kref) > /* check if last port ref was dropped before tty release */ > if (WARN_ON(port->itty)) > return; > - if (port->xmit_buf) > - free_page((unsigned long)port->xmit_buf); > + free_page((unsigned long)port->xmit_buf); > tty_port_destroy(port); > if (port->ops && port->ops->destruct) > port->ops->destruct(port); -- js suse labs