From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from elvis.franken.de (elvis.franken.de [193.175.24.41]) by smtp.subspace.kernel.org (Postfix) with ESMTP id CCAB825CC6A; Tue, 20 May 2025 06:56:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.175.24.41 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747724212; cv=none; b=gaJInANg8jigSc083fgyMXFropyvxSkIm5vN45+RTixAubQsqKDrc0cwCh1YXmjH45eAzCmvWP8EWqNifemJKMvad8LRAUU59z6uiICY37ehx5EMllzc4zYhxek0X/zY4xCG9vh90JijGOodv4fCc4UPwFyK/P7mkfhixttVfFo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747724212; c=relaxed/simple; bh=obD3W9aalppgKCmnqrg4Z36XY9rCjKoeskW1Vsxn4LA=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Io1qXqlOuiv4GJjvkTNzodLjgqtgNlBsJ2IuLWKJzLFa8akrGdGVQPWyY9ThiMYqA8CEsiG1a5u2A5M6IwGAOutlIMReAg1E9JeQflf97EfOEIiXnXbISAf1q6iL62XBgqQtXC6/dHT0GHV/fjFRFSEpFQYERXdCFtQovWuscQ8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de; spf=pass smtp.mailfrom=alpha.franken.de; arc=none smtp.client-ip=193.175.24.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=alpha.franken.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=alpha.franken.de Received: from uucp by elvis.franken.de with local-rmail (Exim 3.36 #1) id 1uHGu1-0006iP-00; Tue, 20 May 2025 08:56:41 +0200 Received: by alpha.franken.de (Postfix, from userid 1000) id 3FA21C05FC; Tue, 20 May 2025 08:50:36 +0200 (CEST) Date: Tue, 20 May 2025 08:50:36 +0200 From: Thomas Bogendoerfer To: Gregory CLEMENT Cc: Huacai Chen , Jiaxun Yang , Vladimir Kondratiev , =?iso-8859-1?Q?Th=E9o?= Lebrun , Tawfik Bayouk , Thomas Petazzoni , linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] MIPS: SMP: Move the AP sync point before the non-parallel aware functions Message-ID: References: <20250505-hotplug-paralell-fix-v1-1-86f222cb6d90@bootlin.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: <20250505-hotplug-paralell-fix-v1-1-86f222cb6d90@bootlin.com> On Mon, May 05, 2025 at 02:57:58PM +0200, Gregory CLEMENT wrote: > When CONFIG_HOTPLUG_PARALLEL is enabled, the code executing before > cpuhp_ap_sync_alive() is executed in parallel, while after it is > serialized. The functions set_cpu_sibling_map() and set_cpu_core_map() > were not designed to be executed in parallel, so by moving the > cpuhp_ap_sync_alive() before cpuhp_ap_sync_alive(), we then ensure > they will be called serialized. > > The measurement done on EyeQ5 did not show any relevant boot time > increase after applying this patch. > > Reported-by: Huacai Chen > Signed-off-by: Gregory CLEMENT > --- > Hello, > > As discussed last week [1], this is the patch that fixes the potential > issue with the functions set_cpu_sibling_map() and set_cpu_core_map(). > > Gregory applied to mips-next with a Fixes tag added Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]