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=-6.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 27957C433ED for ; Wed, 5 May 2021 08:11:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01C60610A5 for ; Wed, 5 May 2021 08:11:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231829AbhEEIMq (ORCPT ); Wed, 5 May 2021 04:12:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:37332 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229744AbhEEIMq (ORCPT ); Wed, 5 May 2021 04:12:46 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 81A5561078; Wed, 5 May 2021 08:11:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620202310; bh=2laNnaXDtXu5mpdO9hMOxhzvS3BWXU53ZPRV+2GL3xw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pvB3jtbocymI5+N/cmAdFfshGMT2Gqlj33c1jFLXzQnjjrpzhGwcsAjkEjAVW6tEq fV79+JTOntOEO1Nnrzd8y6W3i8Ft22A2cjnCUOnzaOuSoqYAMloBdFLn3K3xI/Qj5i UMI2kz6tCK9CnRILxn8n3BWwxwEG03bi/Ktl3VbQ= Date: Wed, 5 May 2021 10:11:47 +0200 From: Greg Kroah-Hartman To: Paul Menzel Cc: linux-usb@vger.kernel.org, LKML , Mathias Nyman , linux-pci@vger.kernel.org Subject: Re: `quirk_usb_handoff_xhci` takes 60 ms with ASM1042 Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Wed, May 05, 2021 at 09:57:44AM +0200, Paul Menzel wrote: > Dear Linux folks, > > > On an Asus F2A85-M PRO, BIOS 6601 11/25/2014, with an ASM1042 SuperSpeed USB > Host Controller [1b21:1042], and the xHCI drivers built as modules > > CONFIG_USB_XHCI_PCI=m > CONFIG_USB_XHCI_HCD=m > > `quirk_usb_handoff_xhci` takes 60 ms, which is 15 % of the time to reaching > `run_init_process()`. I addded some prints, showing the f > > [ 0.308841] pci 0000:03:00.0: PCI->APIC IRQ transform: INT A -> IRQ > 17 > [ 0.369858] pci 0000:03:00.0: handshake done with timeout = 0 > [ 0.369862] pci 0000:03:00.0: hc_init reached > [ 0.369865] pci 0000:03:00.0: second handshake done > [ 0.369869] pci 0000:03:00.0: third handshake done > [ 0.369909] pci 0000:03:00.0: quirk_usb_early_handoff+0x0/0x670 took > 59661 usecs > […] > [ 0.415223] Run /lib/systemd/systemd as init process > > Is there a way to optimize this, or move it out “the hot path”? That's the hardware taking so long, all that function does is make some PCI calls to the device. If the driver is built as a module, there should not be any "hot path" here as the module is loaded async when the device is discovered, right? What is waiting for this module to load in order to cause your init to stall? Perhaps fix your initramfs logic or build the driver into the kernel itself to take it off of this "load all the modules and wait" path? thanks, greg k-h