From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 19862CA9EC5 for ; Mon, 12 Oct 2026 14:28:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=jJkYG1PF/wRZtcnLQD4tSTi4HXCWksgCTc7BhPtqd9g=; b=meY3kC+KIQt28uSXImhUlyK7Q6 hgliDustpgmmg/REx9uKgQbBwEgJZeeLk/ZhIhsHB9luqzPNzmOVjW9bJFAel8f2YFQdAL2MxJV6M 0g+JrLAPJtl48pJ46ChSxVzTiujuH5y/+U2vxgNNlLp9k9oxt5HkP8G8lJSv10DSHWAARQVb60CRf /VlkcET5meKJkG+azUVQnK4EHHWXbLzqneA44CNvDW+2prrXP9Yi0BsQY8Uk0yM8UrAfkK77ZmOUf DrW2YG1I/UgDybaknx1K4WUWdD9oLx/0io+LOHun5Vr7WnB8ehH5ZbyogyG8j3fD0Syalna1C/es9 m4NlOyKA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xGH0Z-0000000Agad-3ORQ; Mon, 12 Oct 2026 14:28:07 +0000 Received: from sea.source.kernel.org ([2600:3c0a:e001:78e:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xGH0Z-0000000AgaS-25Pf for linux-nvme@lists.infradead.org; Mon, 12 Oct 2026 14:28:07 +0000 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id D611841959; Mon, 12 Oct 2026 14:28:04 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 72B361F0089B; Mon, 12 Oct 2026 14:28:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791815284; bh=jJkYG1PF/wRZtcnLQD4tSTi4HXCWksgCTc7BhPtqd9g=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=oMf6Ze/1bhc0nbfftS6JAU2tp3+zT5Dv1XEt5AjMVEHsWQIwOtG1GqJY0XccSF5lL 929hXp/lLWitwAKomo8ZfuiSnqY0AjpWZDVHH7dSr/EzDQJbSkkt2iQEc1I7La4AxD YdarSXunGk5KxIGvtMjHVAJH2j3LirSM8dTXt6GQDzzXXs6zr61Gal6cC8D9G1uK0Q c0kMbrOmGZmpgMy6QX8DLE//WxUptTAgt5yIzwP5hi2dUiKM5t0/iBptjp/jYLlIex j5UHdSznIqRwkBrgSun+AIlSj+uTABJEOHA7cXn/IERzrgQ84ySL7rTglMCsI4/rEm /0ti4WotsrNwA== Date: Mon, 12 Oct 2026 08:28:02 -0600 From: Keith Busch To: Naman Jain Cc: linux-nvme@lists.infradead.org, Jens Axboe , Christoph Hellwig , Sagi Grimberg , Michael Kelley , linux-hyperv@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 3/3] nvme-pci: defer completions when rescheduling is needed Message-ID: References: <20261009050556.2817978-1-namjain@linux.microsoft.com> <20261009050556.2817978-4-namjain@linux.microsoft.com> <8aba4809-6655-4bfd-a83a-25c5ab816645@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8aba4809-6655-4bfd-a83a-25c5ab816645@linux.microsoft.com> X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Mon, Oct 12, 2026 at 12:17:38PM +0530, Naman Jain wrote: > > The disable_irq_nosync still does non-posted transactions for msi and > > msi-x. NVMe has a shortcut for msi, but there's currently nothing for > > msi-x. For that case, I have a prep patch I consulted with Thomas, and > > the result is below. I'm delayed sending it out while catching up from > > travel, but I think this will be even more efficient. > > > > Thanks for sharing. I'll give it a try. IIUC, after your patch goes in, I > should be using disable_irq_nowait() in above and see better performance. Yes, exactly. It should save hundreds of CPU cycles on every switch from irq to polling. > Please correct me if I am wrong. I'll monitor your patch in LKML for future > versions. I need a user for the new API. NVMe is the only one I have in mind right now, so this new irq disable would have to be tied to the series that does the adaptive polling.