From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B108524A7E8 for ; Wed, 15 Jan 2025 13:41:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=205.220.177.32 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736948498; cv=none; b=jJ14NM+4zSjB13QYhOemHLAkVsYfGCfwAJcXJr9VNPIBJ+BReuBG4UvaFNrtkvj0HubvcXew92fqz4un5foF1Mn/VIM2RPIWWbg8aoV1WNYMPmES01dDqRl/J3etACNmVK08Xu84kJO0pLCrrADuvXPDD7gNU8HOzaZYM7f5Jr4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736948498; c=relaxed/simple; bh=MG9Fvo68WunKPinicjfEQdVySLI70g2uLMLvvH57g98=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Y6s5Fl2BHkhX8V2R1w21CUR6+OwnmtRipLViMvGzb8lMk2XVoXmXWqnZN3sJd74G3clfKP92xmV3X3Ki5RmpUSeLNP7XcLqs8MzSy1PwchfSwR+VDrTnXZH2BDLF4vPvCQQ8Gnktljt8zUy8NJZyzVHbd072MUQNhi+JaIIdGUE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com; spf=pass smtp.mailfrom=oracle.com; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b=PIghlftC; arc=none smtp.client-ip=205.220.177.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=oracle.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=oracle.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="PIghlftC" Received: from pps.filterd (m0333520.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 50FCiosh012988; Wed, 15 Jan 2025 13:41:23 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-transfer-encoding:date:from:message-id:mime-version :subject:to; s=corp-2023-11-20; bh=LYYAWYAPXbPdJUuftz4VdyUlXvYvK pKImP3GoCYjVGM=; b=PIghlftCHtK+abB4hg1McQsus7metoTQCCE2AO71AUi61 ZyU0uQfFHboAZBYuavtprp5o14VQLeru8S3M+gs3V4nNRy/gzXY9HQxU9MYTufJB LUOMTIrFSA1Up+R+1H2Sqze9+J9W+A5+t+gSo02SsljjpprK2bX6mROJL5DlEpPo EeIwJRoPMa0PktjmHjK9Tn0lfHtNJ5CA0bwUx1YHQsJQCMgMSrEoE57cbsqDVGNV mTJoYT7EaIWPzI6WTBJEspFRWkzeIVRj5FUk1R1RRkJIzmvuQTPmY6Ii3WQMJjoL Io8FhlQQ2rNepyo+Xx/XY31DM0e3y38m2S/asRjXg== Received: from iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta02.appoci.oracle.com [147.154.18.20]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 443gpcr7r9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 15 Jan 2025 13:41:22 +0000 (GMT) Received: from pps.filterd (iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 50FCpdBl020444; Wed, 15 Jan 2025 13:41:19 GMT Received: from localhost.localdomain (dhcp-10-191-135-68.vpn.oracle.com [10.191.135.68]) by iadpaimrmta02.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTP id 443f3fsvea-1; Wed, 15 Jan 2025 13:41:19 +0000 From: Imran Khan To: anna-maria@linutronix.de, frederic@kernel.org, tglx@linutronix.de Cc: linux-kernel@vger.kernel.org Subject: [PATCH 0/2] Handle timers added to offlined CPU(s). Date: Thu, 16 Jan 2025 00:41:09 +1100 Message-Id: <20250115134111.2703089-1-imran.f.khan@oracle.com> X-Mailer: git-send-email 2.34.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1057,Hydra:6.0.680,FMLib:17.12.68.34 definitions=2025-01-15_05,2025-01-15_02,2024-11-22_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 bulkscore=0 adultscore=0 spamscore=0 suspectscore=0 phishscore=0 malwarescore=0 mlxscore=0 mlxlogscore=791 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2411120000 definitions=main-2501150103 X-Proofpoint-GUID: AkCV7RtvJ47mPHguU0HXZwAAU6CE1cvL X-Proofpoint-ORIG-GUID: AkCV7RtvJ47mPHguU0HXZwAAU6CE1cvL This patchset is in continuation of issue discussed in [1]. Currently there is a possibilty that users of add_timer_on, can (mistakenly) use it for starting a timer on an offlined cpu. As expected such timers will not give desired result. This patchset: i. (PATCH 1) WARNs users of add_timer_on, if they are using it with offlined CPU. ii. (PATCH 2) Introduces an alternative interface that could be used, to ensure that timer gets started only on an online cpu. Imran Khan (2): timers: WARN if add_timer_on is used with offlined cpu. timers: introduce timer_try_add_on_cpu. include/linux/timer.h | 1 + kernel/time/timer.c | 39 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 40 insertions(+) base-commit: e7bb221a638962d487231ac45a6699fb9bb8f9fa [1]: https://lore.kernel.org/all/0a83e9e1-3e85-4c33-bec8-6b60e6216bd8@oracle.com/ -- 2.34.1