From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outgoing2021.csail.mit.edu (outgoing2021.csail.mit.edu [128.30.2.78]) (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 F0688364DC; Fri, 26 Jul 2024 06:35:02 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=128.30.2.78 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721975705; cv=none; b=Cmb9rR12GLA6VA7ZJNwEVo18NgU1dUzHS18ptQ0dCzv7kQutf1TgE/QsODOzP3TkkeYh5ovA8Y74q4dj6jnxcx1IhYla1gUjF8xYzHmoNkhFwc0XfDZrlLyNUIXYnxkamUGrPa1EELpAfioREJhzSBdk5UIMlgeuyYCCfuCl08U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721975705; c=relaxed/simple; bh=PZfSsz3ulJHFXIi/lJFlfTJ3zWld9zetH28g4ZxlSck=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ZCXf6jkbJoGYut4wpH/GAplPb1oA146nxBHZFxBzOTuUstyjK/0mqFoKYTAQ4jHvbylYPzC2CsnQEFbA+uswUWtyRnPDRpn84bj8dlV+mYjF+N9xHMJjsDgJbcaJDSZcrsECSa3DXOuc8UdpousoDLfOYxZvJ9EjSzH9B+HMiT4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=csail.mit.edu; spf=pass smtp.mailfrom=csail.mit.edu; dkim=pass (2048-bit key) header.d=outgoing.csail.mit.edu header.i=@outgoing.csail.mit.edu header.b=LmyYzhqd; arc=none smtp.client-ip=128.30.2.78 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=csail.mit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=csail.mit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=outgoing.csail.mit.edu header.i=@outgoing.csail.mit.edu header.b="LmyYzhqd" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=outgoing.csail.mit.edu; s=test20231205; 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:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=/9kziFIezmJwmyR7yuupUk0XJgkW6rjlPdbESAqvOlE=; t=1721975703; x=1722839703; b=LmyYzhqdZIVirmIVediROdSKUU8w2ffuegr0re9hIn/uBLIwOTSjNgPIyD8GZDv6d0bPRFr2qfL aeFqsH36I7hmqxlHVo/Zivuc5Vnt0sdye5GyOHHclCBkROOe0e6C1Ir4R59k3vEz5UYierRoFONas RCT3zQrW4QvrsZ1vbQ5ZEXjBTfuuI5qG+EfqN0b5Y7Vn/1hWL+GVDKgWGdZrRGtC+IiiTv0iV6xts Y9HYPd6BPdg/Nak7JrSlI6XsHKnaxyBWu9UO1NBvZTF9tFpQ25ebPhfyfgHsfnq7olXVHyN1+xrW0 CiGFj0UfGqKUKxNrHmxjvO4EC+DSMKLXQD5g==; Received: from [172.179.10.40] (helo=csail.mit.edu) by outgoing2021.csail.mit.edu with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1sXEXc-007RmA-56; Fri, 26 Jul 2024 02:35:00 -0400 Date: Fri, 26 Jul 2024 06:34:53 +0000 From: "Srivatsa S. Bhat" To: Dexuan Cui Cc: Saurabh Singh Sengar , Nuno Das Neves , KY Srinivasan , Haiyang Zhang , "wei.liu@kernel.org" , "linux-hyperv@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Saurabh Singh Sengar Subject: Re: [PATCH] Drivers: hv: vmbus: Deferring per cpu tasks Message-ID: References: <1721885164-6962-1-git-send-email-ssengar@linux.microsoft.com> <133be5cb-761e-4646-96ec-b6b53f0c1097@linux.microsoft.com> <20240725153519.GA21016@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net> Precedence: bulk X-Mailing-List: linux-hyperv@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: On Fri, Jul 26, 2024 at 12:01:33AM +0000, Dexuan Cui wrote: > > From: Saurabh Singh Sengar > > Sent: Thursday, July 25, 2024 8:35 AM > > Subject: Re: [PATCH] Drivers: hv: vmbus: Deferring per cpu tasks > > Without the patch, I think the current CPU uses IPIs to let the other > CPUs, one by one, run the function calls, and synchronously waits > for the function calls to finish. > > IMO the patch is not "Deferring per cpu tasks". "Defer" means "let it > happen later". Here it schedules work items to different CPUs, and > the work items immediately start to run on these CPUs. > > I would suggest a more accurate subject: > Drivers: hv: vmbus: Run hv_synic_init() concurrently > It would be great to call out the "why" as well in the title, something like: Drivers: hv: vmbus: Speed-up booting by running hv_synic_init() concurrently Regards, Srivatsa Microsoft Linux Systems Group