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 45467C25B79 for ; Mon, 20 May 2024 15:37:56 +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=ahJhPS46ZZMHjFu06tvpsLUT3cnOc4KGb+AYS8CfPbM=; b=mHMeIFre7D07gvPxK09u/wHrKR BVmHZvgNUoJuoajk1S8Gv53B32m/4IgtnOzbytn/3/gWXyy3wEtDcWD9nxRJO2oIEIAbKa4rJSedq uOnB3oOUw6AJBsGD9Mv9rek7NLnP00jJC3mutQBy0T2GcDYJz6u7Yjd8yeZnzmLHz3g83iQmXBjLA 9rcJnkZg0kwtDuGLexeV2ebbl19Cz4Cb01r69SxZaT4R5MO0HK2I2j30UqUFFIUTil2ycyqUx7fUF w7OU8+NnVGYuFlcqE90mGV2iJSvD/Rac4aEyd6te9v9iFbr0ufS8yf/9oaD1UzUbaNHKX+NvnEfpf tKM25wow==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1s955C-0000000Eroj-3ZMs; Mon, 20 May 2024 15:37:50 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1s9559-0000000Ero4-2Vbz for linux-nvme@lists.infradead.org; Mon, 20 May 2024 15:37:48 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 595D368BFE; Mon, 20 May 2024 17:37:43 +0200 (CEST) Date: Mon, 20 May 2024 17:37:42 +0200 From: Christoph Hellwig To: Thomas Gleixner Cc: Keith Busch , Ming Lei , Christoph Hellwig , Keith Busch , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] nvme-pci: allow unmanaged interrupts Message-ID: <20240520153742.GB921@lst.de> References: <20240510141459.3207725-1-kbusch@meta.com> <20240510141459.3207725-2-kbusch@meta.com> <20240510151047.GA10486@lst.de> <87r0e7mt9w.ffs@tglx> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87r0e7mt9w.ffs@tglx> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240520_083747_799205_61A1A77F X-CRM114-Status: GOOD ( 13.53 ) 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 Sun, May 12, 2024 at 08:35:55AM +0200, Thomas Gleixner wrote: > That's expected as you pin the I/O operation on the isolated CPUs which > in turn makes them use the per CPU queue. > > The isolated CPUs are only excluded for device management interrupts, > but not for the affinity spread of the queues. We'll probably need a version of isolcpus that also excludes the interrupt spread given that users are asking for it. And I'd much prefer that over adding radom module options to every driver to disable managed interrupts.