Re: [PATCH] x86 idle APM: delete apm_cpu_idle(), and its use of pm_idle

From: Ingo Molnar <mingo@elte.hu>
To: Len Brown <lenb@kernel.org>
Cc: Jiri Kosina <jkosina@suse.cz>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Andi Kleen <andi@firstfloor.org>,
	"H. Peter Anvin" <hpa@zytor.com>,
	Stephen Rothwell <sfr@canb.auug.org.au>,
	Andrew Morton <akpm@linux-foundation.org>,
	LKML <linux-kernel@vger.kernel.org>,
	x86@kernel.org, linux-pm@lists.linux-foundation.org,
	Henrique de Moraes Holschuh <hmh@hmh.eng.br>,
	Thomas Gleixner <tglx@linutronix.de>,
	Ondrej Zary <linux@rainbow-software.org>
Subject: Re: [PATCH] x86 idle APM: delete apm_cpu_idle(), and its use of pm_idle
Date: Thu, 31 Mar 2011 08:56:22 +0200	[thread overview]
Message-ID: <20110331065622.GE5938@elte.hu> (raw)
In-Reply-To: <alpine.LFD.2.02.1103302311500.2444@x980>

* Len Brown <lenb@kernel.org> wrote:

> From: Len Brown <len.brown@intel.com>
> 
> There is some doubt whether the APM idle feature
> to call into the BIOS from the idle loop is reliable.
> Certainly it was known to fail on some machines,
> but more importantly, APM machines have not shipped
> for a decade and so finding machines to test the code
> is problematic.
> 
> After this patch, systems running in APM mode will
> simply run default_idle() and HALT without calling
> into the BIOS from their idle loop.
> 
> This deletes a much-maligned modular user of the (pm_idle)()
> function pointer.
> 
> Signed-off-by: Len Brown <len.brown@intel.com>

Ok, this should have far less negative impact on old hardware.

Acked-by: Ingo Molnar <mingo@elte.hu>

Thanks,

	Ingo