From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 7A4642E620 for ; Thu, 30 May 2024 17:01:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717088488; cv=none; b=EDflmDlTSqvQxdbvbNGFM9SjiT7VR2ZzfyxbFemWp6khceqRA/pQX0PdGNsYVObByOAvbeVQwH6wFUQVsMJamj8fP1Gxam+tGvASLM9DFZ+9+UKsGpRg0WOLnB4P8mOmwOeY3Xs5XyNCHgMrRPSF2jmWN5HzsM/GEIOcXzGx/aE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717088488; c=relaxed/simple; bh=4ZRb5QcsUZly9r2lBK0l4VbJCqK2xQtX2LOCg/b9BBY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jOFR1RBr+sjgKOjrfN1g1w/jkwF1lHkTJwaVCeQLO387MpGnZ6Xsc2kTXqknevMZZiTLyBR7xJKNLi4//L4S3kp1IIDNb5d7y0EpRhPYXzbr6TeNDmG9LnI7EEuhbRcxxJpi5LnEI7g2BJz9O+CgwBu3jFXCpd/wnHeq40GNpd8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=JffzGdbL; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="JffzGdbL" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1717088486; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=4ZRb5QcsUZly9r2lBK0l4VbJCqK2xQtX2LOCg/b9BBY=; b=JffzGdbLxg9UiIve4qz7xW4grUE1GpAwykXaxQbfa/d4rT1VoZ1+0RSuyQ586Yss9CPBzX YrgqP4IUYfQqdmHRUUZ4VCzi45evvO+NXVFqbgXS7zrzmUZ3Ix7gKj2qycLI653V7iR67Z 8Lvq3xgxJovKyuB92ZmGlvClCHfV2GU= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-624-cAx2fVLPOHGgX7RwXtIWlw-1; Thu, 30 May 2024 13:01:22 -0400 X-MC-Unique: cAx2fVLPOHGgX7RwXtIWlw-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.rdu2.redhat.com [10.11.54.8]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C15631C0512A; Thu, 30 May 2024 17:01:21 +0000 (UTC) Received: from fedora (unknown [10.45.224.55]) by smtp.corp.redhat.com (Postfix) with SMTP id 5F935C15BB9; Thu, 30 May 2024 17:01:19 +0000 (UTC) Received: by fedora (nbSMTP-1.00) for uid 1000 oleg@redhat.com; Thu, 30 May 2024 13:01:21 -0400 (EDT) Date: Thu, 30 May 2024 13:01:18 -0400 From: Oleg Nesterov To: Frederic Weisbecker Cc: Ingo Molnar , Nicholas Piggin , Peter Zijlstra , Phil Auld , Thomas Gleixner , Chris von Recklinghausen , linux-kernel@vger.kernel.org Subject: Re: [PATCH] tick/nohz_full: don't abuse smp_call_function_single() in tick_setup_device() Message-ID: References: <20240522151742.GA10400@redhat.com> <20240528122019.GA28794@redhat.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: X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.8 On 05/30, Frederic Weisbecker wrote: > > Looks good, but can we have a WARN_ONCE(tick_do_timer_cpu != tick_do_timer_boot_cpu) > right before that, just to make sure our assumptions above are right forever and > the boot CPU hasn't stopped the tick up to that point? Sure, I thought about the additional sanity checks too. Although I had something different in mind. Frederic, et al, I am on private trip again without my working laptop, can't read the code. I'll reply on Saturday, OK? Thanks for review! Oleg.