From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965052AbWGJXtd (ORCPT ); Mon, 10 Jul 2006 19:49:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965057AbWGJXtd (ORCPT ); Mon, 10 Jul 2006 19:49:33 -0400 Received: from ug-out-1314.google.com ([66.249.92.169]:48833 "EHLO ug-out-1314.google.com") by vger.kernel.org with ESMTP id S965052AbWGJXtc (ORCPT ); Mon, 10 Jul 2006 19:49:32 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references; b=j2yoOkZntPap2m7P7pVJo41fqOXYo/DeYKTpn/H3VrhqE5+VNkiZfLYHzhQvrY6P/WAcLDVWYa5hndwWfcT2HdiiLSRWW91uE8da4bm+7uTy+EwT13GOYlmRMMei4VLy/55R4Iqx5/RiPJDLkpWEXbquSP5T7y0hJjELWmgGUTo= Message-ID: <9e4733910607101649m21579ae2p9372cced67283615@mail.gmail.com> Date: Mon, 10 Jul 2006 19:49:31 -0400 From: "Jon Smirl" To: "Alan Cox" Subject: Re: tty's use of file_list_lock and file_move Cc: lkml In-Reply-To: <9e4733910607101604j16c54ef0r966f72f3501cfd2b@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <9e4733910607100810r6e02f69g9a3f6d3d1400b397@mail.gmail.com> <1152552806.27368.187.camel@localhost.localdomain> <9e4733910607101027g5f3386feq5fc54f7593214139@mail.gmail.com> <1152554708.27368.202.camel@localhost.localdomain> <9e4733910607101535i7f395686p7450dc524d9b82ae@mail.gmail.com> <1152573312.27368.212.camel@localhost.localdomain> <9e4733910607101604j16c54ef0r966f72f3501cfd2b@mail.gmail.com> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org How about the use of lock/unlock_kernel(). Is there some hidden global synchronization going on? Every time lock/unlock_kernel() is used there is a tty_struct available. My first thought would be to turn this into a per tty spinlock. Looking at where it is used it looks like it was added to protect all of the VFS calls. I see no obvious coordination with other ttys that isn't handled by other locks. -- Jon Smirl jonsmirl@gmail.com