linux-kernel - Re: [mm][RFC][PATCH 0/11] mm accessor updates.

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20091218051754.GC417@elte.hu>
Date:	Fri, 18 Dec 2009 06:17:54 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Christoph Lameter <cl@...ux-foundation.org>
Cc:	Peter Zijlstra <peterz@...radead.org>,
	Andi Kleen <andi@...stfloor.org>,
	"Paul E. McKenney" <paulmck@...ux.vnet.ibm.com>,
	KAMEZAWA Hiroyuki <kamezawa.hiroyu@...fujitsu.com>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-mm@...ck.org" <linux-mm@...ck.org>,
	"akpm@...ux-foundation.org" <akpm@...ux-foundation.org>,
	minchan.kim@...il.com
Subject: Re: [mm][RFC][PATCH 0/11] mm accessor updates.


* Christoph Lameter <cl@...ux-foundation.org> wrote:

> On Thu, 17 Dec 2009, Peter Zijlstra wrote:
> 
> > > That is why I think that the accessors are a good first step.
> >
> > They're not, they're daft, they operate on a global resource mm_struct, 
> > that's the whole problem, giving it a different name isn't going to solve 
> > anything.
> 
> It is not about naming. The accessors hide the locking mechanism for 
> mmap_sem. Then you can change the locking in a central place.
> 
> The locking may even become configurable later. Maybe an embedded solution 
> will want the existing scheme but dual quad socket may want a distributed 
> reference counter to avoid bouncing cachelines on faults.

Hiding the locking is pretty much the worst design decision one can make.

	Ingo
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/