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 X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 55A72C3F2D1 for ; Sat, 29 Feb 2020 02:52:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2FB4E24697 for ; Sat, 29 Feb 2020 02:52:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726785AbgB2Cwh (ORCPT ); Fri, 28 Feb 2020 21:52:37 -0500 Received: from relay12.mail.gandi.net ([217.70.178.232]:40481 "EHLO relay12.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726046AbgB2Cwg (ORCPT ); Fri, 28 Feb 2020 21:52:36 -0500 Received: from localhost (c-71-238-64-75.hsd1.or.comcast.net [71.238.64.75]) (Authenticated sender: josh@joshtriplett.org) by relay12.mail.gandi.net (Postfix) with ESMTPSA id 3EC1F200007; Sat, 29 Feb 2020 02:52:30 +0000 (UTC) Date: Fri, 28 Feb 2020 18:52:28 -0800 From: Josh Triplett To: Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg Cc: linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH] nvme: Check for readiness more quickly, to speed up boot time Message-ID: <20200229025228.GA203607@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org After initialization, nvme_wait_ready checks for readiness every 100ms, even though the drive may be ready far sooner than that. This delays system boot by hundreds of milliseconds. Reduce the delay, checking for readiness every millisecond instead. Boot-time tests on an AWS c5.12xlarge: Before: [ 0.546936] initcall nvme_init+0x0/0x5b returned 0 after 37 usecs ... [ 0.764178] nvme nvme0: 2/0/0 default/read/poll queues [ 0.768424] nvme0n1: p1 [ 0.774132] EXT4-fs (nvme0n1p1): mounted filesystem with ordered data mode. Opts: (null) [ 0.774146] VFS: Mounted root (ext4 filesystem) on device 259:1. ... [ 0.788141] Run /sbin/init as init process After: [ 0.537088] initcall nvme_init+0x0/0x5b returned 0 after 37 usecs ... [ 0.543457] nvme nvme0: 2/0/0 default/read/poll queues [ 0.548473] nvme0n1: p1 [ 0.554339] EXT4-fs (nvme0n1p1): mounted filesystem with ordered data mode. Opts: (null) [ 0.554344] VFS: Mounted root (ext4 filesystem) on device 259:1. ... [ 0.567931] Run /sbin/init as init process Signed-off-by: Josh Triplett --- drivers/nvme/host/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c index a4d8c90ee7cc..04174a40b9b0 100644 --- a/drivers/nvme/host/core.c +++ b/drivers/nvme/host/core.c @@ -2074,7 +2074,7 @@ static int nvme_wait_ready(struct nvme_ctrl *ctrl, u64 cap, bool enabled) if ((csts & NVME_CSTS_RDY) == bit) break; - msleep(100); + usleep_range(1000, 2000); if (fatal_signal_pending(current)) return -EINTR; if (time_after(jiffies, timeout)) { -- 2.25.1