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 CBD0F4204B; Sat, 27 Jul 2024 12:53:30 +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=1722084813; cv=none; b=gvadUY6pJBDltgMh0I3oN+pI+cVnjrJOflfFoSeACiBuz67zEA48bLBWb1Xxt99XbYvBibV49kPT3lIZ9+9PWjYk7wAVRbtFwWn/+eqM1xu+0kHUi4DoryPpvleKGleVYxE7ZTEVgqaYWlzc15TJWFou54eveXvuDmASl1O9VW4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1722084813; c=relaxed/simple; bh=43nsIiMLcI0BhYal9OGjHJm5ys+DnQ1ANMeM2pJt9Fk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=E7SjgTBSGMX+hcX8l2I5vfPuIwbQCWcoIaq/JosfqYgr8u5IE0SsNpkzEidH5qbnfA5Pw2MnHfJzRaYTphKSB5EJy1PNmBlrkmUIGY2epk1GXkhxKqDcUH+fjtbQkvFaYHTUPL1xcP9GH8S6onDCmrVYC1ICR9ZfO5EefWJYq44= 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=haWmD0Cn; 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="haWmD0Cn" 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=JC33cJseZjIq4zuXKHq4PMMlt37bhXvQFX2NLrHqo4U=; t=1722084811; x=1722948811; b=haWmD0CnJQUK6FnTYPCpXEGzQrCJpvbo/+WEwtdTa6+Cfo65a7X4vEuscq5mu6cm3S85QKCO0la I/x8bH6+pjPa7CbpqT7yKGzcUkDGo6Qu9wWLO+EgYrCIhQD9tvSOUcmzICu7kcWMZPScs/nOovSmO 8k2P0jHcnoDT1B4q6mSZFXoUhnXbAZpFL3iW0JYw6K8K6OVb84Ac9gcbQd31cfaXEiwsyWqRbSZpO yuiAJziiaOuL8m8luhaGqnH5K4jGAkaXiu9Pc39x5ikpN2ZLx7r1yJaaEGXZsy08MOQ3HZkW1Yb1t JX1CQsy/NqSmG71O/TygRetAFFGwCENa+E0A==; 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 1sXgvJ-00Ae4C-A1; Sat, 27 Jul 2024 08:53:21 -0400 Date: Sat, 27 Jul 2024 12:53:15 +0000 From: "Srivatsa S. Bhat" To: Saurabh Singh Sengar Cc: Dexuan Cui , 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> <20240726112619.GA10862@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: <20240726112619.GA10862@linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net> On Fri, Jul 26, 2024 at 04:26:19AM -0700, Saurabh Singh Sengar wrote: > On Fri, Jul 26, 2024 at 06:34:53AM +0000, Srivatsa S. Bhat wrote: > > 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 > > Thanks, I can also rephrase it like below if sounds fine to you: > > Drivers: hv: vmbus: Optimize boot time by concurrent execution of hv_synic_init() > Sure, that sounds good too. Regards, Srivatsa Microsoft Linux Systems Group