From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1754207AbcH2QfU (ORCPT <rfc822;w@1wt.eu>);
        Mon, 29 Aug 2016 12:35:20 -0400
Received: from mga09.intel.com ([134.134.136.24]:54176 "EHLO mga09.intel.com"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1751195AbcH2QfT (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Mon, 29 Aug 2016 12:35:19 -0400
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.28,597,1464678000"; 
   d="scan'208";a="1048741463"
Date: Mon, 29 Aug 2016 12:45:40 -0400
From: Keith Busch <keith.busch@intel.com>
To: Andy Lutomirski <luto@kernel.org>
Cc: Jens Axboe <axboe@fb.com>, linux-nvme@lists.infradead.org,
        Christoph Hellwig <hch@lst.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] nvme: Enable autonomous power state transitions
Message-ID: <20160829164540.GE19986@localhost.localdomain>
References: <cover.1472462539.git.luto@kernel.org>
 <88cc7972617eec58a81877d933604e0f0e342e43.1472462539.git.luto@kernel.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <88cc7972617eec58a81877d933604e0f0e342e43.1472462539.git.luto@kernel.org>
User-Agent: Mutt/1.5.23 (2014-03-12)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, Aug 29, 2016 at 02:25:46AM -0700, Andy Lutomirski wrote:
> +	/*
> +	 * By default, allow up to 25ms of APST-induced latency.  This will
> +	 * have no effect on non-APST supporting controllers (i.e. any
> +	 * controller with APSTA == 0).
> +	 */
> +	ctrl->apst_max_latency_ns = 25000000;

Any objection to making this a module parameter? 25ms default sounds
reasonable, but I would still like the option to not ever initialize
APST on a capable device.