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 3AF5D16F265; Tue, 18 Nov 2025 11:04:23 +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=1763463865; cv=none; b=XWw9Gj6zlPZHG63cT9Q6ZAmMA83tukTqlH8E7UwAjIFw8Lma/vsSc6vozU0mZmMQW+cgT3UuNE4bT482nN7OT7VDGVXFqfCTq+PxEqyDqMY3rq5avJyDFZ1ZtATzYmsCSz16WDhbxK47LFGBN6U+1a9DwQ4ls07vsfGDG2NEv1M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763463865; c=relaxed/simple; bh=qtqCvrv7JopV9CrfUBT92DXWqjaVx3AbXuBW1w/juo4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=BSdwYI7Lf1Gol1+WiPQCLp1LCDrmduutdpjruIuNQm4rOed05qpd77RDgqsIs7udtZbYN6ysys6DaBMB47mOfZRELp47BNg0HglfjWFhbAaQE7Z4LQSPrhDtIjIHzUx3hNfQs2Rdfzd8tkK4tZOIXyRv3K6RuFefz8UashXkTnA= 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=Cj9EiWc2; 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="Cj9EiWc2" 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=EVH/E+cL9bjStuAWv383+yn1qkoEiFkrAZCT1+EtgyM=; b=Cj9EiWc2Sq8gA2zJyUEXEtiK5Q jTgvs7k46HKvmrwmYz8I0XbF3drDwknKoOcfXlnp+xXG5qboNLbZ3W0Ebm61G7V2YH6+/LSWNwKr+ etBFOrVXqId65g1kJ6MzmS/ZUbR8hr6QTs/btnWtShFaqM/pFohFHsn9H8FINDSDwvEUCdvzDFFWu bFrXGB+H5uZyaJpwKY/PmWvsPPQ2ndzIglUogYb1MQiuIzt0Q58AhxgadIGLBe9jXApBlb3qjMH5z xWB0js1EKOPaXGQNvEbLrho6Nh7fDDWJ0NMf9ovMzN51p42zmeVXk5Xmd2tCawt/oNyQxLHaJXT3Q OXSSvDDA==; 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 1vLIdo-00000009Swl-1NNn; Tue, 18 Nov 2025 10:08:52 +0000 Received: by noisy.programming.kicks-ass.net (Postfix, from userid 1000) id 5FBBF30029E; Tue, 18 Nov 2025 12:04:17 +0100 (CET) Date: Tue, 18 Nov 2025 12:04:17 +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: <20251118110417.GI4068168@noisy.programming.kicks-ass.net> References: <20251112080526.3971392-1-dapeng1.mi@linux.intel.com> <20251118110309.GP3245006@noisy.programming.kicks-ass.net> Precedence: bulk X-Mailing-List: linux-perf-users@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: <20251118110309.GP3245006@noisy.programming.kicks-ass.net> On Tue, Nov 18, 2025 at 12:03:09PM +0100, Peter Zijlstra wrote: > 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). Updated patch now sits in queue/perf/urgent.