Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933303AbaFQPvC (ORCPT ); Tue, 17 Jun 2014 11:51:02 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:50159 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933084AbaFQPvA (ORCPT ); Tue, 17 Jun 2014 11:51:00 -0400 MIME-Version: 1.0 In-Reply-To: References: <1402680562-8328-1-git-send-email-ming.lei@canonical.com> <1402680562-8328-3-git-send-email-ming.lei@canonical.com> Date: Tue, 17 Jun 2014 23:50:57 +0800 Message-ID: Subject: Re: [RFC PATCH 2/2] block: virtio-blk: support multi virt queues per virtio-blk device From: Ming Lei To: Stefan Hajnoczi Cc: Jens Axboe , linux-kernel , "Michael S. Tsirkin" , linux-api@vger.kernel.org, Linux Virtualization , Stefan Hajnoczi , Paolo Bonzini Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 17, 2014 at 10:40 AM, Stefan Hajnoczi wrote: > On Sat, Jun 14, 2014 at 1:29 AM, Ming Lei wrote: >> Firstly this patch supports more than one virtual queues for virtio-blk >> device. >> >> Secondly this patch maps the virtual queue to blk-mq's hardware queue. >> >> With this approach, both scalability and performance problem can be improved. >> >> Signed-off-by: Ming Lei >> --- >> drivers/block/virtio_blk.c | 75 ++++++++++++++++++++++++++++++++------------ >> 1 file changed, 55 insertions(+), 20 deletions(-) >> >> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c >> index f63d358..e0d077d 100644 >> --- a/drivers/block/virtio_blk.c >> +++ b/drivers/block/virtio_blk.c >> @@ -16,6 +16,8 @@ >> >> #define PART_BITS 4 >> >> +#define MAX_NUM_VQ 16 > > It would be nice to allocate virtqueues dynamically instead of > hardcoding the limit. virtio-scsi also allocates virtqueues > dynamically. virtio-scsi may have lots of LUN, but virtio-blk only has one disk which needn't lots of hardware queues. Also it doesn't matter since it isn't part of ABI. If change on virtio_blk_config is agreed, both host side and guest side can choose to support dynamic length or pre-defined length freely. Thanks, -- Ming Lei -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/