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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 10138C49ED7 for ; Mon, 16 Sep 2019 13:40:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E26BD214DE for ; Mon, 16 Sep 2019 13:40:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2387478AbfIPNk0 (ORCPT ); Mon, 16 Sep 2019 09:40:26 -0400 Received: from mga04.intel.com ([192.55.52.120]:53651 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387440AbfIPNk0 (ORCPT ); Mon, 16 Sep 2019 09:40:26 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga104.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 16 Sep 2019 06:40:25 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,512,1559545200"; d="scan'208";a="185840360" Received: from mattu-haswell.fi.intel.com (HELO [10.237.72.170]) ([10.237.72.170]) by fmsmga008.fm.intel.com with ESMTP; 16 Sep 2019 06:40:25 -0700 Subject: Re: Event ring is full when do iozone test on UAS storage To: Peter Chen Cc: "linux-usb@vger.kernel.org" References: <20190916094305.GB21844@b29397-desktop> From: Mathias Nyman Message-ID: <0aae13f2-04cf-f45a-e6ee-4bf9e515faba@linux.intel.com> Date: Mon, 16 Sep 2019 16:42:18 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190916094305.GB21844@b29397-desktop> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On 16.9.2019 12.41, Peter Chen wrote: > Hi Mathias, > > I met "event ring full error" like below, this error is met when > I do iozone test on UAS storage at v4.19.35 kernel, but not meet > this error at linux-next tree (08/24). The same host and test > UAS storage device are used. This issue is due to xhci_handle_event > does not return 0 long time, maybe the xHC speed is fast enough > at that time. If I force the xhci_handle_event only run 100 times > before update ERST dequene pointer, it will not occur this error. > I did not see any changes for xhci_handle_event at the latest code, > so in theory, it should have this issue too. Do you think if we need > to improve xhci_handle_event to avoid event ring? Possibly. We need to check the details of what types of events the ring is filled with, and why handling them takes so long. does irqsoff tracing show anything blocking interrupts for long? It's also possible that we don't get interrupts early enough. Either if interupts are moderated, or event ring is filled with events that don't generate interrupts (BEI flag set). -Mathias