linux-kernel - Re: [PATCH] RFC: nomadik: expand timesource to 63 bits

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: <4CDD18F9.5090005@stericsson.com>
Date:	Fri, 12 Nov 2010 11:37:45 +0100
From:	Linus Walleij <linus.walleij@...ricsson.com>
To:	Thomas Gleixner <tglx@...utronix.de>
Cc:	Uwe Kleine-König 
	<u.kleine-koenig@...gutronix.de>,
	john stultz <johnstul@...ibm.com>,
	Rabin VINCENT <rabin.vincent@...ricsson.com>,
	Nicolas Pitre <nico@...xnic.net>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	Colin Cross <ccross@...gle.com>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH] RFC: nomadik: expand timesource to 63 bits

Thomas Gleixner wrote:
> On Fri, 12 Nov 2010, Linus Walleij wrote:
>> Uwe Kleine-König wrote:
>>
>>> Instead of implementing sched_clock for each architecture seperatly,
>>> wouldn't it be nice to have a generic sched_clock that uses the
>>> architecture's clocksource?  I tried to implement that some time ago,
>>> but tglx shoot it down because of locking problems.
>> I was and still am a big fan of this approach, I am willing to help
>> testing it if you want to dust off this patch set...
> 
> sched_clock is not necessarily the same as the current clocksource.

IIRC Uwe:s approach was that if and only if you would want to use
the clocksource for sched_clock() you provide a special flag on
the clocksource, and it will be attempted to be used for sched_clock().

Incidentally the dual use of a single free-running timer as both
single clocksource and sched_clock() baseline seem to creep up in
a lot of embedded platforms...

Yours,
Linus Walleij
--
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/