linux-kernel - Re: [PATCH] SLUB use cmpxchg

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 for Android: free password hash cracker in your pocket

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

Message-ID: <Pine.LNX.4.64.0708271401070.6435@schroedinger.engr.sgi.com>
Date:	Mon, 27 Aug 2007 14:04:07 -0700 (PDT)
From:	Christoph Lameter <clameter@....com>
To:	Mathieu Desnoyers <mathieu.desnoyers@...ymtl.ca>
cc:	Peter Zijlstra <peterz@...radead.org>, akpm@...ux-foundation.org,
	linux-kernel@...r.kernel.org, mingo@...hat.com
Subject: Re: [PATCH] SLUB use cmpxchg_local

I think the simplest solution may be to leave slub as done in the patch 
that we developed last week. The arch must provide a cmpxchg_local that is 
performance wise the fastest possible. On x86 this is going to be the 
cmpxchg_local on others where cmpxchg is slower than interrupt 
disable/enable this is going to be the emulation that does

interrupt disable

cmpchg simulation

interrupt enable

If we can establish that this is not a performance regression then we have 
a clean solution source code wise. It also minimizes the interrupt holdoff 
for the non-cmpxchg_local arches. However, it means that we will have to 
disable interrupts twice for the slow path. If that is too expensive then 
we need a different solution.

-
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/