From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 9B26D1993AE; Thu, 25 Jul 2024 15:23:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721921004; cv=none; b=H0F/4amMg8FMLUrn/BY19LycDk7UxGftjbUUinunbZj+PFq/LUWo/bUHqtBJI1p2bVdKQjXYxaOL9Pk/SVxiVHrghKROC7bc8FX/Wsw6lc/a5T3j2s/0hHMgK3WQOdhIDgcDJ9Lb/HNiefJhGkKHVB5gY/so26RKtzVhqE2s3tQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721921004; c=relaxed/simple; bh=gISgBJP8K+0f5fkIHLXqx+gYvibvOs2vBfW4ph9EQ14=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=gpQOSCYJtGiiIguzwu/wurf+JTprQbwHMM2me3Vi5/IibgvBRvKmmRHOaq36HlEkKXa9lzXfrk6O9Hj8WgvisUXaj/czL46d6OhTrDUFdPJzFNHdy0ZuDel/LCf4iEH4U98G/a76o8SPFQnvVuLvFtuPbK0nByC4/GvVICRzFrw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=raIEqyh/; arc=none smtp.client-ip=13.77.154.182 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) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="raIEqyh/" Received: from [10.0.0.114] (c-67-182-156-199.hsd1.wa.comcast.net [67.182.156.199]) by linux.microsoft.com (Postfix) with ESMTPSA id F26F120B7165; Thu, 25 Jul 2024 08:23:22 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com F26F120B7165 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1721921003; bh=f/OdYnIaYGe0Uwf7xV80gfw5zzsB5T+crnI+/IOcs3E=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=raIEqyh/TO3whk0f3/80L36IhTzzUoNtuAHI3ksnoZI6+qcE/CSMf29qRXzIBfEU6 siS2oW3ZzSM+IDRWxL9n4zYuU/DuZvwvhVONrOk6pqe0Go2grgZ2rvxNTvwjQUtRUT SLDJ4x+UlE0v8NTW3sHT2SjKwq7VpOACW7MvFHQ8= Message-ID: <133be5cb-761e-4646-96ec-b6b53f0c1097@linux.microsoft.com> Date: Thu, 25 Jul 2024 08:23:21 -0700 Precedence: bulk X-Mailing-List: linux-hyperv@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] Drivers: hv: vmbus: Deferring per cpu tasks To: Saurabh Sengar , kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Cc: ssengar@microsoft.com, srivatsa@csail.mit.edu References: <1721885164-6962-1-git-send-email-ssengar@linux.microsoft.com> Content-Language: en-US From: Nuno Das Neves In-Reply-To: <1721885164-6962-1-git-send-email-ssengar@linux.microsoft.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 7/24/2024 10:26 PM, Saurabh Sengar wrote: > Currently on a very large system with 1780 CPUs, hv_acpi_init takes > around 3 seconds to complete for all the CPUs. This is because of > sequential synic initialization for each CPU. > > Defer these tasks so that each CPU executes hv_acpi_init in parallel > to take full advantage of multiple CPUs. I think you mean hv_synic_init() here, not hv_acpi_init()? > > This solution saves around 2 seconds of boot time on a 1780 CPU system, > that around 66% improvement in the existing logic. > > Signed-off-by: Saurabh Sengar > --- > drivers/hv/vmbus_drv.c | 33 ++++++++++++++++++++++++++++++--- > 1 file changed, 30 insertions(+), 3 deletions(-) > LGTM otherwise. Reviewed-by: Nuno Das Neves