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 X-Spam-Level: X-Spam-Status: No, score=-8.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 E1E81C10F27 for ; Tue, 10 Mar 2020 17:45:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B5E4A20727 for ; Tue, 10 Mar 2020 17:45:54 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="j8x9MPHQ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726776AbgCJRpy (ORCPT ); Tue, 10 Mar 2020 13:45:54 -0400 Received: from mail-wr1-f67.google.com ([209.85.221.67]:38717 "EHLO mail-wr1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726546AbgCJRpy (ORCPT ); Tue, 10 Mar 2020 13:45:54 -0400 Received: by mail-wr1-f67.google.com with SMTP id t11so17042096wrw.5 for ; Tue, 10 Mar 2020 10:45:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:references:from:message-id:date:user-agent:mime-version :in-reply-to:content-language:content-transfer-encoding; bh=d/psDyluLfP8VAnyoMEYUqJfPwvyShiYm+45UmmHdLQ=; b=j8x9MPHQetz6fADEyfehSxKYV0FcqE8n6fArfJSHhLEiFolTmkSmgDNXG/9F7iZwYj /jdT61WDymSC61AJe6DVJiy4u8DaXRlgddVidkVPFhJmpVF1AINdRd8Dph5HIUFWcDvi e1G8UT1gq6nqzUuNNGwR1MEzkziIhF8hWqlofP5XnvjVtPNZ6bSnDBmZuUTVsnio2xeL dJ74Bi6vaJ3uicfZipVyYPqLat9aG2Ous9Edsq+JBRYg6im1opMfnTjF1Y9mC0m8EzWb KoJ+pO4QoXPp0qAif2YABwOKIFMTMr/jtgxt306KunlYTQXw/U7xraeKWYT1RAwTpF/9 +qeg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=d/psDyluLfP8VAnyoMEYUqJfPwvyShiYm+45UmmHdLQ=; b=e+zZK/uVNapNigsf/f9DBIAKIcRziwdxkrNoOzIHhP7V3QpA/zuuzFs/feei8SVIIS 0EbA+203fdrgV9mhDlxahnkOSOsDHEEtjTgOW+VBmo5syDe/OifgaZKq0JF8ATQPE9k5 d7PkFWoqUrQ7VBTE4DJ60Nd/cbmvHp0MmEApM6E65xxN+y3RCyFYZHYXVS6bdInbeOUD g4ICvqqypnQljQDCQDlzH2nIYazBuv+hwS4QcMwtrP23qxR5cIOdN/zvBZ/fb7fRxDbY r4+NeNrv5dy8/uQq+LweiL4Ep26rfCsGomMvCglbvHeq/uhJ6n3HC+U+NLjzxAXr5m8d A2Lg== X-Gm-Message-State: ANhLgQ2K7/O+vkEEF66DafOaA/CfE04B2Z26CXz0NCmAcAmhIdTjUyuJ U+roBhf8j826P2EAmxqE7mA= X-Google-Smtp-Source: ADFU+vuv8sf3SPncgVRM4YcSn2dRkoPzGBRyvrRDJbZeh/v0ikvaBuNr50qUk4GcjyxeqUNjd5ICIA== X-Received: by 2002:adf:fc82:: with SMTP id g2mr29972762wrr.117.1583862351957; Tue, 10 Mar 2020 10:45:51 -0700 (PDT) Received: from [10.83.36.153] ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id r28sm70331565wra.16.2020.03.10.10.45.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 10 Mar 2020 10:45:51 -0700 (PDT) Subject: Re: [PATCH v2 4/4] serial: core: Refactor uart_unlock_and_check_sysrq() To: Andy Shevchenko , Greg Kroah-Hartman , linux-serial@vger.kernel.org References: <20200310174337.74109-1-andriy.shevchenko@linux.intel.com> <20200310174337.74109-4-andriy.shevchenko@linux.intel.com> From: Dmitry Safonov <0x7f454c46@gmail.com> Message-ID: <42c6b5b9-af15-ef7d-ea55-2fca0fd6ae18@gmail.com> Date: Tue, 10 Mar 2020 17:45:45 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.2 MIME-Version: 1.0 In-Reply-To: <20200310174337.74109-4-andriy.shevchenko@linux.intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-serial-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org On 3/10/20 5:43 PM, Andy Shevchenko wrote: > Refactor uart_unlock_and_check_sysrq() to: > > - explicitly show that we release a port lock which makes > static analyzers happy: > > CHECK drivers/tty/serial/serial_core.c > .../serial_core.c:3290:17: warning: context imbalance in 'uart_unlock_and_check_sysrq' - unexpected unlock > > - use flags instead of irqflags to avoid confusion with IRQ flags > > - provide one return point > > - be more compact > > Signed-off-by: Andy Shevchenko Thanks! Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com> > --- > v2: move sysrq_ch declaration inside branch (Dmitry) > drivers/tty/serial/serial_core.c | 23 ++++++++++------------- > include/linux/serial_core.h | 3 +-- > 2 files changed, 11 insertions(+), 15 deletions(-) > > diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c > index e3f8e641e3a7..203697465afc 100644 > --- a/drivers/tty/serial/serial_core.c > +++ b/drivers/tty/serial/serial_core.c > @@ -3286,22 +3286,19 @@ int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch) > } > EXPORT_SYMBOL_GPL(uart_prepare_sysrq_char); > > -void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long irqflags) > +void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long flags) > +__releases(&port->lock) > { > - int sysrq_ch; > + if (port->has_sysrq) { > + int sysrq_ch = port->sysrq_ch; > > - if (!port->has_sysrq) { > - spin_unlock_irqrestore(&port->lock, irqflags); > - return; > + port->sysrq_ch = 0; > + spin_unlock_irqrestore(&port->lock, flags); > + if (sysrq_ch) > + handle_sysrq(sysrq_ch); > + } else { > + spin_unlock_irqrestore(&port->lock, flags); > } > - > - sysrq_ch = port->sysrq_ch; > - port->sysrq_ch = 0; > - > - spin_unlock_irqrestore(&port->lock, irqflags); > - > - if (sysrq_ch) > - handle_sysrq(sysrq_ch); > } > EXPORT_SYMBOL_GPL(uart_unlock_and_check_sysrq); > > diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h > index 7a025042e0bb..cab896c60e35 100644 > --- a/include/linux/serial_core.h > +++ b/include/linux/serial_core.h > @@ -447,8 +447,7 @@ extern void uart_insert_char(struct uart_port *port, unsigned int status, > > extern int uart_handle_sysrq_char(struct uart_port *port, unsigned int ch); > extern int uart_prepare_sysrq_char(struct uart_port *port, unsigned int ch); > -extern void uart_unlock_and_check_sysrq(struct uart_port *port, > - unsigned long irqflags); > +extern void uart_unlock_and_check_sysrq(struct uart_port *port, unsigned long flags); > extern int uart_handle_break(struct uart_port *port); > > /* > -- Dima