From: Matt Sealey <matt@genesi-usa.com>
To: Russell King - ARM Linux <linux@arm.linux.org.uk>
Cc: Arnd Bergmann <arnd@arndb.de>,
Linux ARM Kernel ML <linux-arm-kernel@lists.infradead.org>,
LKML <linux-kernel@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Ingo Molnar <mingo@redhat.com>,
John Stultz <john.stultz@linaro.org>,
Ben Dooks <ben@simtec.co.uk>
Subject: Re: One of these things (CONFIG_HZ) is not like the others..
Date: Mon, 21 Jan 2013 17:01:30 -0600 [thread overview]
Message-ID: <CAKGA1b=R+KJEJx1KmBy4oshy23QVJ1=Q9qXDyrzmdMAj3bN_uw@mail.gmail.com> (raw)
In-Reply-To: <20130121224526.GA23505@n2100.arm.linux.org.uk>
On Mon, Jan 21, 2013 at 4:45 PM, Russell King - ARM Linux
<linux@arm.linux.org.uk> wrote:
> On Mon, Jan 21, 2013 at 10:30:07PM +0000, Arnd Bergmann wrote:
>> On Monday 21 January 2013, Matt Sealey wrote:
>> > So is that a bug in that it is not available to ARM right now, a bug
>> > in that it would be impossible for anyone on ARM to have ever tested
>> > this code, or a bug in that it should NEVER be enabled for ARM for
>> > some reason? John? Ingo? :)
>> >
>>
>> I think it's a bug that it's not available. That does not look intentional.
>
> What's a bug? kernel/Kconfig.hz not being available? No, it's
> intentional. (See my replies).
The bug I saw as real is that CONFIG_SCHED_HRTICK is defined only in
kernel/Kconfig.hz (and used in kernel/sched only) - so if we want that
functionality enabled we will also have to opencode it in
arch/arm/Kconfig. Everyone else, by virtue of using kernel/Kconfig.hz,
gets this config item enabled for free if they have hrtimers or
generic smp helpers.. if I understood what John just said, this means
on ARM, since we don't use kernel/Kconfig.hz and we don't also define
an item for CONFIG_SCHED_HRTICK, the process scheduler is completely
oblivious that we're running in HRT mode?
The thing I don't know is real is if that really matters one bit..
--
Matt Sealey <matt@genesi-usa.com>
Product Development Analyst, Genesi USA, Inc.
next prev parent reply other threads:[~2013-01-21 23:01 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-21 20:01 One of these things (CONFIG_HZ) is not like the others Matt Sealey
2013-01-21 20:41 ` Arnd Bergmann
2013-01-21 21:00 ` John Stultz
2013-01-21 21:12 ` Russell King - ARM Linux
2013-01-21 22:18 ` John Stultz
2013-01-21 22:44 ` Russell King - ARM Linux
2013-01-22 8:27 ` Arnd Bergmann
2013-01-21 22:20 ` Matt Sealey
2013-01-21 22:42 ` Russell King - ARM Linux
2013-01-21 23:23 ` Matt Sealey
2013-01-21 23:49 ` Russell King - ARM Linux
2013-01-22 0:09 ` Matt Sealey
2013-01-22 0:26 ` Matt Sealey
2013-01-21 21:14 ` Matt Sealey
2013-01-21 22:36 ` John Stultz
2013-01-21 22:49 ` Russell King - ARM Linux
2013-01-21 22:54 ` Matt Sealey
2013-01-21 23:13 ` Russell King - ARM Linux
2013-01-21 23:30 ` Matt Sealey
2013-01-22 0:02 ` Russell King - ARM Linux
2013-01-22 0:38 ` John Stultz
2013-01-22 0:51 ` John Stultz
2013-01-22 1:06 ` Matt Sealey
2013-01-22 1:18 ` Russell King - ARM Linux
2013-01-22 1:56 ` Matt Sealey
2013-01-22 1:31 ` John Stultz
2013-01-22 2:10 ` Matt Sealey
2013-01-31 21:31 ` Thomas Gleixner
2013-01-21 21:02 ` Matt Sealey
2013-01-21 22:30 ` Arnd Bergmann
2013-01-21 22:45 ` Russell King - ARM Linux
2013-01-21 23:01 ` Matt Sealey [this message]
2013-01-21 21:03 ` Russell King - ARM Linux
2013-01-21 23:23 ` Tony Lindgren
2013-01-22 6:23 ` Santosh Shilimkar
2013-01-22 9:31 ` Arnd Bergmann
2013-01-22 10:14 ` Santosh Shilimkar
2013-01-22 14:51 ` Russell King - ARM Linux
2013-01-22 15:05 ` Santosh Shilimkar
2013-01-28 6:08 ` Santosh Shilimkar
2013-01-29 0:01 ` John Stultz
2013-01-29 6:43 ` Santosh Shilimkar
2013-01-29 10:06 ` Russell King - ARM Linux
2013-01-29 18:43 ` John Stultz
2013-01-22 17:31 ` Arnd Bergmann
2013-01-22 18:59 ` John Stultz
2013-01-22 21:52 ` Tony Lindgren
2013-01-23 5:18 ` Santosh Shilimkar
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