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From: linux@arm.linux.org.uk (Russell King - ARM Linux)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ARM: formalize an IPI for CPU wake-ups
Date: Mon, 11 Jun 2012 19:41:48 +0100	[thread overview]
Message-ID: <20120611184148.GD18267@n2100.arm.linux.org.uk> (raw)
In-Reply-To: <alpine.LFD.2.02.1206111430300.23555@xanadu.home>

On Mon, Jun 11, 2012 at 02:40:24PM -0400, Nicolas Pitre wrote:
> On Mon, 11 Jun 2012, Russell King - ARM Linux wrote:
> 
> > On Mon, Jun 11, 2012 at 01:18:28PM -0400, Nicolas Pitre wrote:
> > > And that message certainly has to go as it may be triggered multiple 
> > > times per second in some use cases here.
> > 
> > That, I interpret, as an attempt to use CPU hotplugging for power
> > saving.
> > 
> > No.  Do not do that.  Under any circumstances.  Not only is the CPU
> > hotplugging code racy in places, it also totally destroys the ability
> > to have threads bound to CPUs, or even interrupts to CPUs.
> 
> [ more comments ommitted ]
> 
> Russell, let me suggest you take the time to read this:
> 
> 	http://lwn.net/Articles/481055/
> 
> then let's restart this conversation if you please.

Same comments apply for exactly the reasons I stated.

  reply	other threads:[~2012-06-11 18:41 UTC|newest]

Thread overview: 27+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-06-11 15:54 [PATCH] ARM: formalize an IPI for CPU wake-ups Nicolas Pitre
2012-06-11 15:57 ` Russell King - ARM Linux
2012-06-11 16:44   ` Nicolas Pitre
2012-06-11 16:51     ` Russell King - ARM Linux
2012-06-11 17:18       ` Nicolas Pitre
2012-06-11 17:41         ` Stephen Boyd
2012-06-11 19:25           ` Russell King - ARM Linux
2012-06-20 16:32             ` Stephen Boyd
2012-07-11  6:34               ` Kukjin Kim
2012-07-30 18:19                 ` Stephen Boyd
2012-08-01  9:42                   ` Kukjin Kim
2012-08-06 20:41                     ` Colin Cross
2012-08-07 17:00                       ` Russell King - ARM Linux
2012-08-08  7:04                         ` Shilimkar, Santosh
2012-08-08 10:39                       ` Kukjin Kim
2012-08-08  6:52                   ` Magnus Damm
2012-08-13 22:09                     ` Stephen Boyd
2012-08-22 19:05                       ` Stephen Boyd
2012-08-22 21:23                         ` Magnus Damm
2012-08-29  7:21                         ` Stephen Boyd
2012-09-08 14:47                           ` Nicolas Pitre
2012-06-11 18:26         ` Russell King - ARM Linux
2012-06-11 18:40           ` Nicolas Pitre
2012-06-11 18:41             ` Russell King - ARM Linux [this message]
2012-06-11 19:11               ` Nicolas Pitre
2012-06-11 19:20                 ` Russell King - ARM Linux
2012-06-11 19:56                   ` Nicolas Pitre

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