From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 4B58C314B6D; Tue, 18 Nov 2025 11:03:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=90.155.92.199 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763463802; cv=none; b=Whvoi4qLRQkvCXsSiyEgSYH/DoUBcGN7RQP+Wkpi7QsgJ4ca9TYazy9iTP3DZN6hfOBjrMzy7xAWBbgWpjgLQTWh09yOC5H7Z2AHt4bVH+4I1GcIbN2mhiNwAF+ws4tbWyEYDbEU2wtPYSAkhQ8bahfFPo3LDTS7nCtDUaHN3tY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763463802; c=relaxed/simple; bh=jisAGFCHJK0LwGpz+zsikyimRU+OHDsc2kEwJIkv2e8=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TQ19LaKBu7mSojlnatfV3jp4TTZA33fKHr8t6rXaBMvsxqkw5ydF7zWh8jKL3iedU78HmxxAcfmjW2TOG/MSLkVosTKDf3wRSHn/C8MZMW9RgoZNEge7E8hKJQ302JA2GGFcDwjBWIJ5MNOWOSUpWIU7ovdXImvDy3lYfHbVx3k= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=kT0w/pYe; arc=none smtp.client-ip=90.155.92.199 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="kT0w/pYe" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=desiato.20200630; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=eutwvmf1cUvRAiETZ2QkQIobb+TPHlTNm40TDuuj8fw=; b=kT0w/pYejSU8Mq8rPn139ZaJmZ 0nWXEj8q0DTE7E4FLz7iOg+O99t1rd5ykIwspC9CNeKbVYioSrwcbERY0FkIVctW1hQA9EYgiTyJa 8+O2wKUmSbgIveGTTWytm/ecWvF5wrpHdG/q8QL3hSQtDjAds7ph4vvEMQEvuAVn4/BJsKEXx/JxF wqOSITh/V+ZmhKkX24vrEbMdI9TxMaPBHEg+8envR7ZpXQNps1G+D4xxEdpKoSdeZjQzqnm5LdZ1Y b+zQI20PySaHoEVMOvdZVQ6XsRJ90hSIoPvK6zaJgnYBCXc1+07siXUHtpgv47LG/0bsU71/xbJsw jAf5Zcjg==; Received: from 77-249-17-252.cable.dynamic.v4.ziggo.nl ([77.249.17.252] helo=noisy.programming.kicks-ass.net) by desiato.infradead.org with esmtpsa (Exim 4.98.2 #2 (Red Hat Linux)) id 1vLIck-00000009SlY-03R2; Tue, 18 Nov 2025 10:07:46 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id D5B3230029E; Tue, 18 Nov 2025 12:03:09 +0100 (CET) Date: Tue, 18 Nov 2025 12:03:09 +0100 From: Peter Zijlstra To: Dapeng Mi Cc: Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , Ian Rogers , 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 Subject: Re: [PATCH] perf: Fix 0 count issue of cpu-clock Message-ID: <20251118110309.GP3245006@noisy.programming.kicks-ass.net> References: <20251112080526.3971392-1-dapeng1.mi@linux.intel.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251112080526.3971392-1-dapeng1.mi@linux.intel.com> On Wed, Nov 12, 2025 at 04:05:26PM +0800, Dapeng Mi wrote: > diff --git a/kernel/events/core.c b/kernel/events/core.c > index f6a08c73f783..77d3af5959c1 100644 > --- a/kernel/events/core.c > +++ b/kernel/events/core.c > @@ -11964,7 +11964,7 @@ static int cpu_clock_event_add(struct perf_event *event, int flags) > > static void cpu_clock_event_del(struct perf_event *event, int flags) > { > - cpu_clock_event_stop(event, flags); > + cpu_clock_event_stop(event, flags | PERF_EF_UPDATE); > } > > static void cpu_clock_event_read(struct perf_event *event) > @@ -12043,7 +12043,7 @@ static int task_clock_event_add(struct perf_event *event, int flags) > > static void task_clock_event_del(struct perf_event *event, int flags) > { > - task_clock_event_stop(event, PERF_EF_UPDATE); > + task_clock_event_stop(event, flags | PERF_EF_UPDATE); > } I think it can both just be: PERF_EF_UPDATE. The only pmu::del() caller hands in flags=0, but if there were to be flags added, we'd have to audit all del methods anyway. Also, the few comments we do have already note that ->del() must do ->stop(EF_UPDATE).