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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 402E2C432C0 for ; Wed, 27 Nov 2019 01:16:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1C6EF2075C for ; Wed, 27 Nov 2019 01:16:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725823AbfK0BQH (ORCPT ); Tue, 26 Nov 2019 20:16:07 -0500 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:8842 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725794AbfK0BQH (ORCPT ); Tue, 26 Nov 2019 20:16:07 -0500 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xAR1C8gJ093805; Tue, 26 Nov 2019 20:15:57 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 2whcxnm1x5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Nov 2019 20:15:57 -0500 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xAR1FvFX101226; Tue, 26 Nov 2019 20:15:57 -0500 Received: from ppma04wdc.us.ibm.com (1a.90.2fa9.ip4.static.sl-reverse.com [169.47.144.26]) by mx0a-001b2d01.pphosted.com with ESMTP id 2whcxnm1ws-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 26 Nov 2019 20:15:57 -0500 Received: from pps.filterd (ppma04wdc.us.ibm.com [127.0.0.1]) by ppma04wdc.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xAR1A3ua006119; Wed, 27 Nov 2019 01:15:55 GMT Received: from b03cxnp07029.gho.boulder.ibm.com (b03cxnp07029.gho.boulder.ibm.com [9.17.130.16]) by ppma04wdc.us.ibm.com with ESMTP id 2wevd78aet-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 27 Nov 2019 01:15:55 +0000 Received: from b03ledav006.gho.boulder.ibm.com (b03ledav006.gho.boulder.ibm.com [9.17.130.237]) by b03cxnp07029.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xAR1FplO15597940 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 27 Nov 2019 01:15:51 GMT Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AB7EAC605A; Wed, 27 Nov 2019 01:15:51 +0000 (GMT) Received: from b03ledav006.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 47D77C6057; Wed, 27 Nov 2019 01:15:51 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav006.gho.boulder.ibm.com (Postfix) with ESMTP; Wed, 27 Nov 2019 01:15:51 +0000 (GMT) Subject: [PATCH 13/14] powerpc/vas: Display process stuck message From: Haren Myneni To: linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, mpe@ellerman.id.au, npiggin@gmail.com, mikey@neuling.org, herbert@gondor.apana.org.au Cc: sukadev@linux.vnet.ibm.com, hbabu@us.ibm.com Content-Type: text/plain; charset="UTF-8" Date: Tue, 26 Nov 2019 17:14:32 -0800 Message-ID: <1574817272.13250.21.camel@hbabu-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.95,18.0.572 definitions=2019-11-26_08:2019-11-26,2019-11-26 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxlogscore=999 mlxscore=0 phishscore=0 lowpriorityscore=0 priorityscore=1501 suspectscore=0 bulkscore=0 impostorscore=0 spamscore=0 clxscore=1015 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1911270008 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Process can not close send window until all requests are processed. Means wait until window state is not busy and send credits are returned. Display debug message in case taking longer to close the window. Signed-off-by: Haren Myneni --- arch/powerpc/platforms/powernv/vas-window.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/arch/powerpc/platforms/powernv/vas-window.c b/arch/powerpc/platforms/powernv/vas-window.c index 1c0788c..9ba354c 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -1186,6 +1186,7 @@ static void poll_window_credits(struct vas_window *window) { u64 val; int creds, mode; + int count = 0; val = read_hvwc_reg(window, VREG(WINCTL)); if (window->tx_win) @@ -1204,10 +1205,25 @@ static void poll_window_credits(struct vas_window *window) creds = GET_FIELD(VAS_LRX_WCRED, val); } + /* + * Takes around few microseconds to complete all pending requests + * and return credits. + * TODO: Issue CRB Kill to stop all pending requests. Need only + * if there is a bug in NX or fault handling in kernel. + */ if (creds < window->wcreds_max) { val = 0; set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(msecs_to_jiffies(10)); + count++; + /* + * Process can not close send window until all credits are + * returned. + */ + if (!(count % 10000)) + pr_debug("%s() pid %d stuck? retries %d\n", __func__, + vas_window_pid(window), count); + goto retry; } } @@ -1221,6 +1237,7 @@ static void poll_window_busy_state(struct vas_window *window) { int busy; u64 val; + int count = 0; retry: val = read_hvwc_reg(window, VREG(WIN_STATUS)); @@ -1229,6 +1246,15 @@ static void poll_window_busy_state(struct vas_window *window) val = 0; set_current_state(TASK_UNINTERRUPTIBLE); schedule_timeout(msecs_to_jiffies(5)); + count++; + /* + * Takes around 5 microseconds to process all pending + * requests. + */ + if (!(count % 10000)) + pr_debug("%s() pid %d stuck? retries %d\n", __func__, + vas_window_pid(window), count); + goto retry; } } -- 1.8.3.1