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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D33EECDB47E for ; Wed, 18 Oct 2023 19:41:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231720AbjJRTlS (ORCPT ); Wed, 18 Oct 2023 15:41:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46198 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231658AbjJRTlO (ORCPT ); Wed, 18 Oct 2023 15:41:14 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4E623B8 for ; Wed, 18 Oct 2023 12:41:12 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B4E99C433C8; Wed, 18 Oct 2023 19:41:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1697658071; bh=79J258HbqH4/kkkD7j45ZgaF2NuqX5EhwfzRK9eenU4=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=B9pjGqVbO3w0VepxJgsuuZ+2xGythRnZdGok8MbNhvzxzv7rIqXUa8SEB7Pk/LilG mXbHCULJ+eGX5+9SkOoOQL7dMWtVlV/Po4UhkaNTA9NeSR3dwvgny2pJXT3GL1WKt/ 9m+mb+xVsy4ZxVRZGlhZwmKeUNvArtskImb/XcAsh75xzcb+pVLXDrbqvMxF6fTKut tVBXV659WY/8uABn1JwS5gsKSoXvvtxLucFH79u+BrjIuFdOVgq0fKX6EC6C6LfVAZ tQu5RDR+YAWOHofxKEn7YN7/omJLXBC1MwIwjrYhKXPa1PcxgQPd6e3nmRDpNStrTP xjE37LbX3JA8Q== Date: Wed, 18 Oct 2023 14:41:09 -0500 From: Bjorn Helgaas To: Ido Schimmel Cc: netdev@vger.kernel.org, linux-pci@vger.kernel.org, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, edumazet@google.com, bhelgaas@google.com, alex.williamson@redhat.com, lukas@wunner.de, petrm@nvidia.com, jiri@nvidia.com, mlxsw@nvidia.com Subject: Re: [RFC PATCH net-next 06/12] PCI: Add debug print for device ready delay Message-ID: <20231018194109.GA1371221@bhelgaas> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231017074257.3389177-7-idosch@nvidia.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Tue, Oct 17, 2023 at 10:42:51AM +0300, Ido Schimmel wrote: > Currently, the time it took a PCI device to become ready after reset is > only printed if it was longer than 1000ms ('PCI_RESET_WAIT'). However, > for debugging purposes it is useful to know this time even if it was > shorter. For example, with the device I am working on, hardware > engineers asked to verify that it becomes ready on the first try (no > delay). > > To that end, add a debug level print that can be enabled using dynamic > debug. Example: > > # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset > # dmesg -c | grep ready > # echo "file drivers/pci/pci.c +p" > /sys/kernel/debug/dynamic_debug/control > # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset > # dmesg -c | grep ready > [ 396.060335] mlxsw_spectrum4 0000:01:00.0: ready 0ms after link toggle > # echo "file drivers/pci/pci.c -p" > /sys/kernel/debug/dynamic_debug/control > # echo 1 > /sys/bus/pci/devices/0000\:01\:00.0/reset > # dmesg -c | grep ready > > Signed-off-by: Ido Schimmel Acked-by: Bjorn Helgaas > --- > drivers/pci/pci.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 59c01d68c6d5..0a708e65c5c4 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -1216,6 +1216,9 @@ static int pci_dev_wait(struct pci_dev *dev, char *reset_type, int timeout) > if (delay > PCI_RESET_WAIT) > pci_info(dev, "ready %dms after %s\n", delay - 1, > reset_type); > + else > + pci_dbg(dev, "ready %dms after %s\n", delay - 1, > + reset_type); > > return 0; > } > -- > 2.40.1 >