From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 9 Apr 2018 12:04:53 +0200 From: Christoph Hellwig To: Ming Lei Cc: Jens Axboe , linux-block@vger.kernel.org, Christian Borntraeger , Stefan Haberland , Keith Busch , stable@vger.kernel.org Subject: Re: [PATCH 2/8] blk-mq: don't keep offline CPUs mapped to hctx 0 Message-ID: <20180409100452.GB11144@lst.de> References: <20180408094814.28953-1-ming.lei@redhat.com> <20180408094814.28953-3-ming.lei@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180408094814.28953-3-ming.lei@redhat.com> List-ID: On Sun, Apr 08, 2018 at 05:48:08PM +0800, Ming Lei wrote: > >From commit 4b855ad37194 ("blk-mq: Create hctx for each present CPU), > blk-mq doesn't remap queue after CPU topo is changed, that said when > some of these offline CPUs become online, they are still mapped to > hctx 0, then hctx 0 may become the bottleneck of IO dispatch and > completion. > > This patch sets up the mapping from the beginning, and aligns to > queue mapping for PCI device (blk_mq_pci_map_queues()). Please kill the now pointless cpu_to_queue_index function. Otherwise looks good: Reviewed-by: Christoph Hellwig