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[2620:137:e000::1:20]) by mx.google.com with ESMTP id y18-20020aa78f32000000b0063b8ab7f91csi7610835pfr.365.2023.04.28.10.08.23; Fri, 28 Apr 2023 10:08:39 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2023-03-30 header.b="EbkYj/Gw"; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346338AbjD1RA7 (ORCPT + 99 others); Fri, 28 Apr 2023 13:00:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40872 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229687AbjD1RAz (ORCPT ); Fri, 28 Apr 2023 13:00:55 -0400 Received: from mx0a-00069f02.pphosted.com (mx0a-00069f02.pphosted.com [205.220.165.32]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 38DFE2703 for ; Fri, 28 Apr 2023 10:00:54 -0700 (PDT) Received: from pps.filterd (m0333521.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 33SF4XSx031617; Fri, 28 Apr 2023 17:00:25 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding; s=corp-2023-03-30; bh=+QMy/l384YvGQZ5Q1IRZPWRi2K6puso7UHybf7DN4AY=; b=EbkYj/GwAotd4c9mOdbYHlF9HjFfE/6WCa8mfFk2QLALMvqnKBdTFvBN+YvU4StSpTPt zVa2mHuopaimttBTU5sFsdYHrbiQA7NVIl5jQ009qpNMx7yUY3gOTX+hz3egRf2LbgKY nRZawliVwClP2dJWw7/Qi5eqmoM7s57HRWWKgFzwI1ylaO7v/of1dfFJCNJ+MbYY5aot UjQ9XXZoMEiv8kEzJRou7dGBfd1/QZ3sadV+C3J2v9VoH+jjrIrzozRb6zg+hR4MvBsg Fp7WCGs4KTescVjI8iYvWKp1UCW0PfR8624VVQt3pSrmSFSO2xCA3n8EkTJFr9NtlrVB NQ== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 3q46gbxwq8-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Fri, 28 Apr 2023 17:00:25 +0000 Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.17.1.19/8.17.1.19) with ESMTP id 33SFlOMh029935; Fri, 28 Apr 2023 17:00:24 GMT Received: from localhost.localdomain (dhcp-10-191-130-53.vpn.oracle.com [10.191.130.53]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 3q461b1n2g-2; Fri, 28 Apr 2023 17:00:23 +0000 From: Imran Khan To: peterz@infradead.org, paulmck@kernel.org, jgross@suse.com, vschneid@redhat.com, yury.norov@gmail.com, tglx@linutronix.de Cc: linux-kernel@vger.kernel.org Subject: [RFC PATCH 1/2] smp: Reduce logging due to dump_stack of CSD waiters. Date: Sat, 29 Apr 2023 03:00:05 +1000 Message-Id: <20230428170006.1241472-2-imran.f.khan@oracle.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230428170006.1241472-1-imran.f.khan@oracle.com> References: <20230428170006.1241472-1-imran.f.khan@oracle.com> MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-04-28_04,2023-04-27_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 phishscore=0 mlxlogscore=915 adultscore=0 malwarescore=0 mlxscore=0 spamscore=0 bulkscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2303200000 definitions=main-2304280136 X-Proofpoint-GUID: uTolTkvX5GzRBumGrt1tMhrKR3wGkRXw X-Proofpoint-ORIG-GUID: uTolTkvX5GzRBumGrt1tMhrKR3wGkRXw X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1764440637944733716?= X-GMAIL-MSGID: =?utf-8?q?1764440637944733716?= If a waiter is waiting for CSD lock, its call stack will not change between first and subsequent hang detection for the same CSD lock. So dump_stack for the waiter only for first time detection. This avoids excessive logging on large scale systems(with hundreds of CPUs) where repetitive dump_stack from hundreds of CPUs can flood the console. Signed-off-by: Imran Khan Reviewed-by: Paul E. McKenney --- kernel/smp.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/smp.c b/kernel/smp.c index ab3e5dad6cfe9..b7ccba677a0a0 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -248,7 +248,8 @@ static bool csd_lock_wait_toolong(struct __call_single_data *csd, u64 ts0, u64 * arch_send_call_function_single_ipi(cpu); } } - dump_stack(); + if (firsttime) + dump_stack(); *ts1 = ts2; return false;