linux-kernel - Re: [RFC][PATCH 0/5] Introduce checks for preemptable code for this_cpu

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]

Date:	Tue, 20 Sep 2011 09:58:41 -0500 (CDT)
From:	Christoph Lameter <cl@...two.org>
To:	Thomas Gleixner <tglx@...utronix.de>
cc:	Valdis.Kletnieks@...edu, Steven Rostedt <rostedt@...dmis.org>,
	linux-kernel@...r.kernel.org, Ingo Molnar <mingo@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Peter Zijlstra <peterz@...radead.org>,
	Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Subject: Re: [RFC][PATCH 0/5] Introduce checks for preemptable code for
 this_cpu_read/write()

On Tue, 20 Sep 2011, Thomas Gleixner wrote:

> > What's the latency hit on those very few locations if we simply put our
> > collective foot down and not support a preemptable version of this_cpu_*()?
> > "Yes, you *could* preempt here, but for our collective sanity that's not
> > supported"...
>
> Full ack.

Latency hit could be very significant in various critical kernel paths.
Especially network subsystem, vm event counters etc.

--
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/