From: "Michael S. Tsirkin" <mst@redhat.com>
To: Stefan Hajnoczi <stefanha@redhat.com>
Cc: fam@euphon.net, linux-scsi@vger.kernel.org, jasowang@redhat.com,
qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org,
target-devel@vger.kernel.org, pbonzini@redhat.com,
Mike Christie <michael.christie@oracle.com>
Subject: Re: [PATCH 00/10] vhost/qemu: thread per IO SCSI vq
Date: Thu, 19 Nov 2020 09:46:26 -0500 [thread overview]
Message-ID: <20201119094315-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <20201118113117.GF182763@stefanha-x1.localdomain>
On Wed, Nov 18, 2020 at 11:31:17AM +0000, Stefan Hajnoczi wrote:
> > My preference has been:
> >
> > 1. If we were to ditch cgroups, then add a new interface that would allow
> > us to bind threads to a specific CPU, so that it lines up with the guest's
> > mq to CPU mapping.
>
> A 1:1 vCPU/vq->CPU mapping isn't desirable in all cases.
>
> The CPU affinity is a userspace policy decision. The host kernel should
> provide a mechanism but not the policy. That way userspace can decide
> which workers are shared by multiple vqs and on which physical CPUs they
> should run.
So if we let userspace dictate the threading policy then I think binding
vqs to userspace threads and running there makes the most sense,
no need to create the threads.
--
MST
next prev parent reply other threads:[~2020-11-19 14:52 UTC|newest]
Thread overview: 47+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-11-12 23:18 [PATCH 00/10] vhost/qemu: thread per IO SCSI vq Mike Christie
2020-11-12 23:19 ` [PATCH 1/1] qemu vhost scsi: add VHOST_SET_VRING_ENABLE support Mike Christie
2020-11-17 11:53 ` Stefan Hajnoczi
2020-12-02 9:59 ` Michael S. Tsirkin
2020-12-02 16:05 ` Michael Christie
2020-11-12 23:19 ` [PATCH 01/10] vhost: remove work arg from vhost_work_flush Mike Christie
2020-11-17 13:04 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 02/10] vhost scsi: remove extra flushes Mike Christie
2020-11-17 13:07 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 03/10] vhost poll: fix coding style Mike Christie
2020-11-17 13:07 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 04/10] vhost: support multiple worker threads Mike Christie
2020-11-12 23:19 ` [PATCH 05/10] vhost: poll support support multiple workers Mike Christie
2020-11-17 15:32 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 06/10] vhost scsi: make SCSI cmd completion per vq Mike Christie
2020-11-17 16:04 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 07/10] vhost, vhost-scsi: flush IO vqs then send TMF rsp Mike Christie
2020-11-17 16:05 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 08/10] vhost: move msg_handler to new ops struct Mike Christie
2020-11-17 16:08 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 09/10] vhost: add VHOST_SET_VRING_ENABLE support Mike Christie
2020-11-17 16:14 ` Stefan Hajnoczi
2020-11-12 23:19 ` [PATCH 10/10] vhost-scsi: create a woker per IO vq Mike Christie
2020-11-17 16:40 ` [PATCH 00/10] vhost/qemu: thread per IO SCSI vq Stefan Hajnoczi
2020-11-17 19:13 ` Mike Christie
2020-11-18 9:54 ` Michael S. Tsirkin
2020-11-19 14:00 ` Stefan Hajnoczi
2020-11-18 11:31 ` Stefan Hajnoczi
2020-11-19 14:46 ` Michael S. Tsirkin [this message]
2020-11-19 16:11 ` Mike Christie
2020-11-19 16:24 ` Stefan Hajnoczi
2020-11-19 16:43 ` Mike Christie
2020-11-19 17:08 ` Stefan Hajnoczi
2020-11-20 8:45 ` Stefan Hajnoczi
2020-11-20 12:31 ` Michael S. Tsirkin
2020-12-01 12:59 ` Stefan Hajnoczi
2020-12-01 13:45 ` Stefano Garzarella
2020-12-01 17:43 ` Stefan Hajnoczi
2020-12-02 10:35 ` Stefano Garzarella
2020-11-23 15:17 ` Stefano Garzarella
2020-11-18 5:17 ` Jason Wang
2020-11-18 6:57 ` Mike Christie
2020-11-18 7:19 ` Mike Christie
2020-11-18 7:54 ` Jason Wang
2020-11-18 20:06 ` Mike Christie
2020-11-19 4:35 ` Jason Wang
2020-11-19 15:49 ` Mike Christie
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