From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 DFAE76BB20 for ; Tue, 21 May 2024 10:07:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716286022; cv=none; b=mF9X5YumPJ0f9nIE75OqMqummEb1aIv2ghOL0kXIzfXwE1UHqD6RgR1oI1ziKI30TOV2KoNrYcN3Tm9na8KFFWWyNGTkc0X9fs0v3iX1WXt4IzGOBTWB2Uobo43cyGs43bejErFN6ibS+QjNYEbxghJjsdCusH3+yznyMph6Xzk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716286022; c=relaxed/simple; bh=jqZc2bJtxtIBJwM/97UqABA4R2EDya0YKbUlffFLnUE=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=bdsMeFYZakXcSRg3Ao4WjgEEdjdGCas94qNzfF0OYFpP03lQx1keQnDqH3FenLB/KF1PQrgFJE8VvWVLVtOMfEH3wAL79wVHcG1Dxjr6TablA4C0RAXehXdYtYBtpGL2/EGBf2dnzLfmcMfTKkux9ay6YrJl/GwziOo4o1I3Lig= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=C6ph+Ugq; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="C6ph+Ugq" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1005FC2BD11; Tue, 21 May 2024 10:07:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1716286021; bh=jqZc2bJtxtIBJwM/97UqABA4R2EDya0YKbUlffFLnUE=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=C6ph+UgqyXtfZIRxRb/DfroOOuKcv1Gl/t/19hLlpXi7xxFMMW8HxBAiNjdXp6Lgr CXMT36Inc8sua/bFzVdlBdwCudNKe6WAb9+avJoIgXehtW6xKAwRXr5KYkGroWvVxI gK8PBa5AoSB1BLO+G+enX1PqVj3IVJCWsoX4Pr6MDMDH3kW4MzHQTDlqg+msX8PlqY SQHimPMaoiXTfRexnlALwPGwXht0OrD3OWKM5sTZSV348deu39cs+eSFpd3m0IDTph noeiKda1I/kRhB6V4HlIlFioB0HuOgL7FPbqRq2D+ipUbt9YGHo2NK5sV9wSfEWuqo dc9IEjN2wVGXA== Date: Tue, 21 May 2024 12:06:58 +0200 From: Frederic Weisbecker To: Thomas Gleixner Cc: Ming Lei , Christoph Hellwig , Keith Busch , Keith Busch , linux-nvme@lists.infradead.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 2/2] nvme-pci: allow unmanaged interrupts Message-ID: References: <20240510141459.3207725-1-kbusch@meta.com> <20240510141459.3207725-2-kbusch@meta.com> <20240510151047.GA10486@lst.de> <87r0e7mt9w.ffs@tglx> <20240520153742.GB921@lst.de> <87a5kjimpq.ffs@tglx> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87a5kjimpq.ffs@tglx> Le Tue, May 21, 2024 at 10:38:25AM +0200, Thomas Gleixner a écrit : > On Tue, May 21 2024 at 10:31, Ming Lei wrote: > > > On Mon, May 20, 2024 at 05:37:42PM +0200, Christoph Hellwig wrote: > >> 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. > > > > BTW, isolcpus has been marked as deprecated, and it can't be adjust > > runtime. > > Which is far from reality as cpusets do not allow to do what isolcpus > does today. > > Also runtime adjusting managed interrupts needs way more thoughts. I'll remove that comment (unless someone beats me at it?). We used to think that cpusets would indeed deprecate isolcpus but for several reasons this will never be the case. Thanks.