From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=13.77.154.182 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793959661; b=u9hgAPfB/aOORNWZNEQVjJkLlyYvgTxINc74X6ZwY57XKmHiHY4BheylbanSAMgkWLuC psd4Jl5+LgcFPXNKeEcynPC5ycJSBW5YnrTw4iwV+e+iAtwekV/9y3i2eyf1AVfc6HZhi rLUklKLX1E1hCNNsPdqX/U/r6DtSxQXNmKl0taxO8sIYdUUQ6xRQvdLXN+IcgyHv0iDJ2 PxAHQPBa/nzpfa3IRwL/jSTfWO+0n5q16SMuy4uWQw0C3VkkBx2F1Bcb/zan34k+49z8i XFPDQXx9EyhuF9gkW0H+EEBpA/qpG5Cb7opVZCqf9X+a3RixQxM3+Jumli6/kl3QtqA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793959661; h=DMARC-Filter:Received:DKIM-Filter:DKIM-Signature:Message-ID:Date: MIME-Version:User-Agent:Subject:To:Cc:References:Content-Language: From:In-Reply-To:Content-Type:Content-Transfer-Encoding:X-Spam-Status: X-Spam-Checker-Version; bh=4KliYQLOkHRMH3GsBEDAYRnBw+vTw59dBjsCMzw0iYU=; b=CMSCDVcs92rWk/9bx4gdFnyGSUBsd7AqPsQ3YwcAclcOrvs3yHzju2g2S3nin7DLbH7k vGmYflH4LEJFS7P5eKEQIfg1Yr1/D5iL4yzYLaVlFhQcH+bakVzpPjokd02m4kp2xWydo 9UWA3EsbD0OSp7vzoOvXmpjOn5PdKrNxbb0MGDd/nOkZIMMKdSexBg+mdBskvf2jnrOmT nM5dT/AJMalz5K5MXVfTE2jRty90OZ7RSsR016e4M3g096mVgOJfW/nSo3onu8peQfhkt c1K9jLETHuXAZpD5SbhyMmL4d1bUMO/Gxz/2XNpsf8PPVwY4du0FlLTxl4s3liV6hOg== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass header.d=linux.microsoft.com header.i=@linux.microsoft.com header.a=rsa-sha256 header.s=default header.b=k9eYQuQk; arc=none smtp.remote-ip=13.77.154.182 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 4C3B9606A326; Fri, 6 Nov 2026 10:07:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 4C3B9606A326 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.a=rsa-sha256 header.s=default header.b=k9eYQuQk Received: from [192.168.1.14] (unknown [52.172.102.187]) by linux.microsoft.com (Postfix) with ESMTPSA id E477D20B7167; Fri, 6 Nov 2026 02:07:30 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com E477D20B7167 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1793959655; bh=4KliYQLOkHRMH3GsBEDAYRnBw+vTw59dBjsCMzw0iYU=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=k9eYQuQkEYzlfycUHHEhM9p5wZCfuJAxVyAbYl5N4IHX5m3HkGBGcFASfj5X3rUbc 0PMffL/CUvRIbGv0jXHfOi68U+vMKDI9CL+OdvYZmFGSb3eVbwf2ymH8/m166JZj+H Td2plXZZGDIkLnaUAdbungHOX6N32uzefqj99IZQ= Message-ID: Date: Fri, 6 Nov 2026 15:37:26 +0530 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 39/47] clocksource: hyper-v: Move CPUHP_AP_HYPERV_TIMER_STARTING post stop_machine() To: Frederic Weisbecker , LKML Cc: "K. Y. Srinivasan" , Daniel Lezcano , Dexuan Cui , Haiyang Zhang , Long Li , Marco Crivellari , Peter Zijlstra , Phil Auld , Thomas Gleixner , Waiman Long , Wei Liu , linux-hyperv@vger.kernel.org, "Paul E. McKenney" References: <20261105163045.38862-1-frederic@kernel.org> <20261105163045.38862-40-frederic@kernel.org> Content-Language: en-US From: Naman Jain In-Reply-To: <20261105163045.38862-40-frederic@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 11/5/2026 10:00 PM, Frederic Weisbecker wrote: > Between CPUHP_TEARDOWN_CPU and CPUHP_AP_OFFLINE, stop_machine executes > all the teardown callbacks while stopping all CPUs in the system. This > doesn't mix-up well with running RT or isolated tasks. > > In order to transition smoothly from global stop_machine to finer > grained synchronization between teardown callbacks and the other CPUs, > a new stop machine post function has been introduced to be executed > after the main one with IRQs still disabled while other CPUs can exit > stop_machine(). > > The teardown callback here simply performs timer and IRQ disablement, > both of which can run concurrently with other CPUs. > > Move it to post stop_machine() accordingly. > > Signed-off-by: Frederic Weisbecker > --- > kernel/cpu.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/kernel/cpu.c b/kernel/cpu.c > index 93b8498e26c4..b49b67ef5ecb 100644 I am unable to correlate the commit message with the change and could not find the rest of the series on lore to get more context. Regards, Naman > --- a/kernel/cpu.c > +++ b/kernel/cpu.c > @@ -1275,7 +1275,7 @@ void clear_tasks_mm_cpumask(int cpu) > static int take_cpu_down(void *_param) > { > struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); > - enum cpuhp_state target = max((int)st->target, CPUHP_AP_TI_GP_TIMER_STARTING); > + enum cpuhp_state target = max((int)st->target, CPUHP_AP_HYPERV_TIMER_STARTING); > int err, cpu = smp_processor_id(); > > /* Ensure this CPU doesn't handle any more interrupts. */ > @@ -1303,7 +1303,7 @@ static int take_cpu_down_post(void *_param) > enum cpuhp_state target = max((int)st->target, CPUHP_AP_OFFLINE); > int cpu = smp_processor_id(); > > - WARN_ON(st->state != CPUHP_AP_TI_GP_TIMER_STARTING); > + WARN_ON(st->state != CPUHP_AP_HYPERV_TIMER_STARTING); > /* > * Invoke the former CPU_DYING callbacks. DYING must not fail! > */