From mboxrd@z Thu Jan 1 00:00:00 1970 From: Toshi Kani Subject: Re: [PATCH v3 0/7] ACPI: Add _OST support for ACPI hotplug Date: Fri, 11 May 2012 11:24:52 -0600 Message-ID: <1336757092.16730.250.camel@misato.fc.hp.com> References: <1336754223-5346-1-git-send-email-toshi.kani@hp.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from g4t0015.houston.hp.com ([15.201.24.18]:9042 "EHLO g4t0015.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932600Ab2EKR12 (ORCPT ); Fri, 11 May 2012 13:27:28 -0400 In-Reply-To: Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Andi Kleen Cc: lenb@kernel.org, linux-acpi@vger.kernel.org, bhelgaas@google.com, shuahkhan@gmail.com, liuj97@gmail.com, linux-kernel@vger.kernel.org On Fri, 2012-05-11 at 10:09 -0700, Andi Kleen wrote: > Toshi Kani writes: > > > This patchset supports ACPI OSPM Status Indication (_OST) method for > > ACPI CPU/memory/container hotplug operations and sysfs eject. After > > ACPI hotplug operation has completed, OSPM calls _OST to indicate the > > result of the operation to the platform. If _OST is not present, this > > patchset has no effect on the platform. > > > > This _OST support can be enabled or disabled with a new config option > > CONFIG_ACPI_HOTPLUG_OST. This option is disabled by default. When > > this option is disabled, this patchset has no effect on the platform. > > Does that control compiling in/out significant sized code? > > Controlling code behaviour by CONFIG option has been long deprecated. > This is always better done as a runtime option. > > Just think what should a distribution who wants to use the same binary > on all systems set. Good question. The OS needs to tell the platform if it supports _OST at boot-time, and has to stick with it. Therefore, this feature may not be enabled/disabled during run-time. Another reason is that this feature depends on ACPI_HOTPLUG_CPU, ACPI_HOTPLUG_MEMORY and ACPI_CONTAINER config options in order to provide consistent behavior among multiple hotplug operations with regarding the _OST support. Thanks, -Toshi