From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E7002C433F5 for ; Wed, 2 Feb 2022 07:55:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=UZlT8n0Q/9JsjsHXY61m9hR2dO2jYUs6RYAAyANKPmU=; b=g7FA6cJAH9dbXFWgacFhtZddGf fmkpeHugvQelIlD1h7F+9182+ZLjSdxda6SKP/LCGORGkU0HChBRKS3s5VQ9ZBVcKBNrGw0QaksOS n2+4f8bheopQWM1TWSlQJrWWtvmf+nhQnkzw3AmSpj3CimcGrcOhR0IDJOqzHWvenF2oMpOEOIVvh 9JeoAb4K0K7W7T8vteWsBnR18s+KnoFxP8RX4HbsRXVvshXJzmvnmndNy6NkQa0D5Z6EXEO/pyIAC KEkzmhZLvqs5OuaHWid4oYjZwATL/5ocTBiW1S9w+NGtw0u+KLFpf+QpIaIB4SNwOT/7E84deSHqh GGhiABdA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nFATt-00EU7R-Ld; Wed, 02 Feb 2022 07:55:09 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nFATr-00EU6W-4p for linux-nvme@lists.infradead.org; Wed, 02 Feb 2022 07:55:08 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 40B9367373; Wed, 2 Feb 2022 08:55:03 +0100 (CET) Date: Wed, 2 Feb 2022 08:55:02 +0100 From: Christoph Hellwig To: Keith Busch Cc: linux-nvme@lists.infradead.org, hch@lst.de, sagi@grimberg.me, Rafael Wysocki , Vidya Sagar Subject: Re: [PATCH] nvme/pci: default to simple suspend Message-ID: <20220202075502.GA18474@lst.de> References: <20220201165006.3074615-1-kbusch@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220201165006.3074615-1-kbusch@kernel.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220201_235507_367559_DC79A4D7 X-CRM114-Status: GOOD ( 15.22 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Feb 01, 2022 at 08:50:06AM -0800, Keith Busch wrote: > There is no complete set of attributes a driver can check to know if > nvme power management is the correct thing to do in a runtime suspend > situation. Every attempt so far to optimize idle power consumption and > resume latency for a particular platform just leads to regressions > elsewhere. > > Default to the simple shutdown since it is the historically safest > option, and provide a user parameter to override it if the user knows > it's safe to use for their platform. Sigh. The platforms really should be asking for a explicit D3cold if they need one..