From owner-freebsd-current@freebsd.org  Sat Jan 30 18:25:24 2016
Return-Path: <owner-freebsd-current@freebsd.org>
Delivered-To: freebsd-current@mailman.ysv.freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org
 [IPv6:2001:1900:2254:206a::19:1])
 by mailman.ysv.freebsd.org (Postfix) with ESMTP id 0415DA72DE7
 for <freebsd-current@mailman.ysv.freebsd.org>;
 Sat, 30 Jan 2016 18:25:24 +0000 (UTC) (envelope-from slw@zxy.spb.ru)
Received: from zxy.spb.ru (zxy.spb.ru [195.70.199.98])
 (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id B801015B5
 for <freebsd-current@freebsd.org>; Sat, 30 Jan 2016 18:25:23 +0000 (UTC)
 (envelope-from slw@zxy.spb.ru)
Received: from slw by zxy.spb.ru with local (Exim 4.86 (FreeBSD))
 (envelope-from <slw@zxy.spb.ru>)
 id 1aPaD3-000Nlp-Bk; Sat, 30 Jan 2016 21:25:21 +0300
Date: Sat, 30 Jan 2016 21:25:21 +0300
From: Slawa Olhovchenkov <slw@zxy.spb.ru>
To: mokhi <mokhi64@gmail.com>
Cc: freebsd-current@freebsd.org
Subject: Re: thread-unsafety problems as spl*() ones are NOP
Message-ID: <20160130182521.GM88527@zxy.spb.ru>
References: <CAByVWPWuqdtZ-5p2+vGf4v+PjjCBkiTQSsZQ06vk-f=bx_TQrQ@mail.gmail.com>
 <CAByVWPWQJ1wP95S59SiWWBa0k9j2+u1az-D04_V1voo99CxqCw@mail.gmail.com>
 <20160130180256.GT37895@zxy.spb.ru>
 <CAByVWPUz2nMuWncsv648BGHReBvtP3r1afAz0LC+WD5tikdYDA@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAByVWPUz2nMuWncsv648BGHReBvtP3r1afAz0LC+WD5tikdYDA@mail.gmail.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
X-SA-Exim-Connect-IP: <locally generated>
X-SA-Exim-Mail-From: slw@zxy.spb.ru
X-SA-Exim-Scanned: No (on zxy.spb.ru); SAEximRunCond expanded to false
X-BeenThere: freebsd-current@freebsd.org
X-Mailman-Version: 2.1.20
Precedence: list
List-Id: Discussions about the use of FreeBSD-current
 <freebsd-current.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-current/>
List-Post: <mailto:freebsd-current@freebsd.org>
List-Help: <mailto:freebsd-current-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-current>, 
 <mailto:freebsd-current-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sat, 30 Jan 2016 18:25:24 -0000

On Sat, Jan 30, 2016 at 09:42:13PM +0330, mokhi wrote:

> i currently only wanna do patch on kbd.c (because i'm sure there is a
> thread-unsafety)
> and i don't want to add anything to spltty() nor splx(), i just wanna
> add things under where they've been used.
> isn't problem with using mutex/spin/lock/unlock etc there?

yes.
currenly spltty act as mutex_lock(&spltty_mutex), like global lock for
all used files. this is also inter-files lock, not only lock inside
only kbd.c.
you need patch all files. all using spltty need to remove
simultaneously.