From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.11]) (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 BE7DB301027; Mon, 8 Dec 2025 05:17:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765171026; cv=none; b=eY+s7LH2PRZzfTG3cOKYOEQLmaToDEMsy0h52R4xUTM90CCF7BPvp0Bul7jRA3MMOIFq98NeB80zKVWQ/oNPDLwJC5jkX/owPM6WMN6TfKv+8+qsmj6k1fAgOs6OJ0mB58vnVlzGr0GSgEvyY0Jp4YYHz3Mo9vNShnfJj6o67Tk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1765171026; c=relaxed/simple; bh=BZIsbDGOFIus+jpCUAw6WchM6meY697FmknZE8eMhmE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=sGjHeNRnYKtNvnnwgf9ILO393IY5KJ/FeY+9i+YEm4tt1OSEPmgTJOSGC9hP5xNUx/ed271MURP09wfjRBVIgu2+6x96wG7NhvgEIjNNqsfO3LVHsBLnM8YkqYwoeMnuq1H55pPPtxF2ylPeHxln8VlJvL/EonhNLqAOaNb/SMY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=exY8YItP; arc=none smtp.client-ip=198.175.65.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="exY8YItP" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1765171022; x=1796707022; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=BZIsbDGOFIus+jpCUAw6WchM6meY697FmknZE8eMhmE=; b=exY8YItPvKYAQL5oyeN4E7+wBulZryP9BptyD8b4ahSY9TcUydysQX7Q +4DktcKlJtDHz2lhrVa6Vn+OT5N6Va34Osear54yln+J4/2miDWr9+a+i 2FamNUCDhMjMENM3aPZZMzZMFtRgqOUU6AJ4gG6Hlh2bOB/QiBL/NZpW1 QqIeLZlgGOFuDeonFlWsp7SwZX+pLukPnC1ioMpp60eaHAzLRsTShmENv 9dU1OPNXD9A3/dbuqtmAdRGeeX+mpIjHHZ4Iy8vGwtMpZbQRzRv73Q4nw jpzAZcJrWf0Kh33dqAwhs3TRgqq7Wu18PxhcJOcigUD6A5kk5+kg5gGyt g==; X-CSE-ConnectionGUID: 0ohBb6/qR+qYrBpC4QJdog== X-CSE-MsgGUID: gffK5bKvQJ+Kwb3svd/BDA== X-IronPort-AV: E=McAfee;i="6800,10657,11635"; a="77430694" X-IronPort-AV: E=Sophos;i="6.20,258,1758610800"; d="scan'208";a="77430694" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2025 21:17:01 -0800 X-CSE-ConnectionGUID: /RsT9KgfTCq02FYmc/EBwA== X-CSE-MsgGUID: F0wKQYwtRteAFiahNyzZgg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.20,258,1758610800"; d="scan'208";a="233214943" Received: from dapengmi-mobl1.ccr.corp.intel.com (HELO [10.124.240.12]) ([10.124.240.12]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Dec 2025 21:16:57 -0800 Message-ID: Date: Mon, 8 Dec 2025 13:16:54 +0800 Precedence: bulk X-Mailing-List: linux-perf-users@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] perf: Fix 0 count issue of cpu-clock To: Ian Rogers , Peter Zijlstra , Ingo Molnar Cc: Arnaldo Carvalho de Melo , Namhyung Kim , Adrian Hunter , Alexander Shishkin , Andi Kleen , Eranian Stephane , linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, Dapeng Mi , Zide Chen , Falcon Thomas , Xudong Hao References: <20251112080526.3971392-1-dapeng1.mi@linux.intel.com> <20251118110309.GP3245006@noisy.programming.kicks-ass.net> <20251118110417.GI4068168@noisy.programming.kicks-ass.net> <20251118112406.GH4067720@noisy.programming.kicks-ass.net> Content-Language: en-US From: "Mi, Dapeng" In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On 12/6/2025 7:44 AM, Ian Rogers wrote: > On Tue, Nov 18, 2025 at 3:24 AM Peter Zijlstra wrote: >> On Tue, Nov 18, 2025 at 07:22:24PM +0800, Mi, Dapeng wrote: >>> On 11/18/2025 7:04 PM, Peter Zijlstra wrote: >>>> On Tue, Nov 18, 2025 at 12:03:09PM +0100, Peter Zijlstra wrote: >>>>> Also, the few comments we do have already note that ->del() must do >>>>> ->stop(EF_UPDATE). > Hi Peter, > > I was trying to do a quick sanity check that other callers of stop > were passing in EF_UPDATE. I wondered if the case of > perf_event_throttle_group with leader sampling has an issue? The > throttle should only happen on an event or group leader that is in > sampling mode, but the group members could be non-sampling with leader > sampling. Sorry for the noise if I'm wrong on this. Fwiw, the other > uses either pass in EF_UPDATE or I think for __perf_event_aux_pause > and __perf_event_overflow the problem isn't relevant. Base on the logic, it looks we need to add the flag EF_UPDATE in perf_event_throttle_group(), but need Peter's confirm.  > > Thanks, > Ian >