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=-8.2 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 7BB1CC43603 for ; Mon, 9 Dec 2019 03:38:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5780520663 for ; Mon, 9 Dec 2019 03:38:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726894AbfLIDim (ORCPT ); Sun, 8 Dec 2019 22:38:42 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:61618 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726860AbfLIDil (ORCPT ); Sun, 8 Dec 2019 22:38:41 -0500 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id xB93bE7A056032; Sun, 8 Dec 2019 22:38:24 -0500 Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wrt10gtcg-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 08 Dec 2019 22:38:24 -0500 Received: from m0098414.ppops.net (m0098414.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id xB93bd7G056740; Sun, 8 Dec 2019 22:38:23 -0500 Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0b-001b2d01.pphosted.com with ESMTP id 2wrt10gtc9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Sun, 08 Dec 2019 22:38:23 -0500 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.0.27/8.16.0.27) with SMTP id xB93Virh024474; Mon, 9 Dec 2019 03:38:22 GMT Received: from b03cxnp07028.gho.boulder.ibm.com (b03cxnp07028.gho.boulder.ibm.com [9.17.130.15]) by ppma04dal.us.ibm.com with ESMTP id 2wr3q63549-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 09 Dec 2019 03:38:22 +0000 Received: from b03ledav004.gho.boulder.ibm.com (b03ledav004.gho.boulder.ibm.com [9.17.130.235]) by b03cxnp07028.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id xB93cLu749807646 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 9 Dec 2019 03:38:21 GMT Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 6A2937805C; Mon, 9 Dec 2019 03:38:21 +0000 (GMT) Received: from b03ledav004.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DCEB07805E; Mon, 9 Dec 2019 03:38:20 +0000 (GMT) Received: from [9.70.82.143] (unknown [9.70.82.143]) by b03ledav004.gho.boulder.ibm.com (Postfix) with ESMTP; Mon, 9 Dec 2019 03:38:20 +0000 (GMT) Subject: [PATCH V2 12/13] powerpc/vas: Display process stuck message From: Haren Myneni To: mpe@ellerman.id.au Cc: hch@infradead.org, mikey@neuling.org, npiggin@gmail.com, herbert@gondor.apana.org.au, linuxppc-dev@lists.ozlabs.org, devicetree@vger.kernel.org, sukadev@linux.vnet.ibm.com In-Reply-To: <1575861522.16318.9.camel@hbabu-laptop> References: <1575861522.16318.9.camel@hbabu-laptop> Content-Type: text/plain; charset="UTF-8" Date: Sun, 08 Dec 2019 19:36:42 -0800 Message-ID: <1575862602.16318.30.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=2019-12-08_07:2019-12-05,2019-12-08 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 lowpriorityscore=0 suspectscore=1 impostorscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 clxscore=1015 priorityscore=1501 bulkscore=0 spamscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-1910280000 definitions=main-1912090030 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 27848d3..578f144 100644 --- a/arch/powerpc/platforms/powernv/vas-window.c +++ b/arch/powerpc/platforms/powernv/vas-window.c @@ -1176,6 +1176,7 @@ 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) @@ -1194,10 +1195,25 @@ 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; } } @@ -1211,6 +1227,7 @@ 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)); @@ -1219,6 +1236,15 @@ 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