From mboxrd@z Thu Jan 1 00:00:00 1970 From: Len Brown Subject: Re: acpi_idle: Very idle Core i7 machine never enters C3 Date: Fri, 05 Feb 2010 12:45:21 -0500 (EST) Message-ID: References: <20100126084740.GA5265@jgarrett.org> <87y6jkee1b.fsf@basil.nowhere.org> <20100205160900.GA2736@jgarrett.org> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Received: from vms173015pub.verizon.net ([206.46.173.15]:64875 "EHLO vms173015pub.verizon.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933643Ab0BERpk (ORCPT ); Fri, 5 Feb 2010 12:45:40 -0500 In-reply-to: <20100205160900.GA2736@jgarrett.org> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Jeff Garrett Cc: Andi Kleen , linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org Jeff, What do you see if you apply just the patch below? Also, in addition to "powertop -d" to show what the kernel requests, please run turbostat to show what the hardware actually did: http://userweb.kernel.org/~lenb/acpi/utils/pmtools-latest/turbostat/turbostat.c eg. # turbostat -d -v sleep 5 thanks, -Len Brown, Intel Open Source Technology Center --- diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 7c0441f..f528625 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -763,7 +763,7 @@ static const struct file_operations acpi_processor_power_fops = { static int acpi_idle_bm_check(void) { u32 bm_status = 0; - +return bm_status; acpi_read_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, &bm_status); if (bm_status) acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_STATUS, 1);