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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 BA6F6C4338F for ; Fri, 20 Aug 2021 21:23:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A345D61130 for ; Fri, 20 Aug 2021 21:23:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237534AbhHTVYP (ORCPT ); Fri, 20 Aug 2021 17:24:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:59126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231200AbhHTVYO (ORCPT ); Fri, 20 Aug 2021 17:24:14 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 36E9E61102; Fri, 20 Aug 2021 21:23:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629494616; bh=DR5+xPR+Dm45+yzNiJITr0ADd0H7NeYcn/WPxNjvYO4=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=nzI84HLBvAMPeG1ykv7lSnTwg9HSJGHa+1mQynmTJaod577O5hGIWJczchrW/Yvw9 gN9mqXq5ATQU/+RGlg4jADIBaJghLKeBa9SzPlCKn5X2ovmVCxYpPwGZISeroKT6S2 iePXYCOa3jS2jBLMIy/r+DVj+cisYKB5w7ZGUPjimly+FEYXAWojvqZ5/MHS4MjhPj deDDIJor6CrRRc/8v30+WoOACy72+QgujSF4YAr8T0nRpYendj+UMZ8j4tvYdaGjok CXXenygYORAqV7aUihNT6RUI9RV3oErzqRgT33ka8B6GqScydu+sDb07u7/YHGEX/4 uBnie7AzOa2YA== Date: Fri, 20 Aug 2021 16:23:34 -0500 From: Bjorn Helgaas To: Krzysztof =?utf-8?Q?Wilczy=C5=84ski?= Cc: Bjorn Helgaas , Bin Lai , Jiang Biao , linux-pci@vger.kernel.org Subject: Re: [PATCH] PCI: Allow scheduling to take place in proc_bus_pci_read() Message-ID: <20210820212334.GA3360706@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20210815150824.96773-1-kw@linux.com> Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org On Sun, Aug 15, 2021 at 03:08:24PM +0000, Krzysztof Wilczyński wrote: > PCI configuration space reads from the /proc/bus/pci for a particular > device, depending on the underlying hardware, can often take several > milliseconds to complete. > > Thus, add a schedule point in proc_bus_pci_read() to reduce the maximum > latency. > > A similar change has already been completed in the past for the sysfs > counterpart in the commit 2ce02a864ac1 ("PCI: Add schedule point in > pci_read_config()"). > > Link: https://lore.kernel.org/r/20200824052025.48362-1-benbjiang@tencent.com > Signed-off-by: Krzysztof Wilczyński Applied to pci/misc for v5.15, thanks! I tweaked your subject line to match 2ce02a864ac1: PCI: Add schedule point in proc_bus_pci_read() > --- > drivers/pci/proc.c | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/drivers/pci/proc.c b/drivers/pci/proc.c > index d32fbfc93ea9..cb18f8a13ab6 100644 > --- a/drivers/pci/proc.c > +++ b/drivers/pci/proc.c > @@ -83,6 +83,7 @@ static ssize_t proc_bus_pci_read(struct file *file, char __user *buf, > buf += 4; > pos += 4; > cnt -= 4; > + cond_resched(); > } > > if (cnt >= 2) { > -- > 2.32.0 >