public inbox for kvm@vger.kernel.org
 help / color / mirror / Atom feed
From: "Michael S. Tsirkin" <mst@redhat.com>
To: Avi Kivity <avi@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>,
	Sheng Yang <sheng@linux.intel.com>,
	Marcelo Tosatti <mtosatti@redhat.com>,
	kvm@vger.kernel.org
Subject: Re: [PATCH 0/8][v2] MSI-X mask emulation support for assigned device
Date: Wed, 20 Oct 2010 19:11:39 +0200	[thread overview]
Message-ID: <20101020171139.GA24188@redhat.com> (raw)
In-Reply-To: <4CBF1541.703@redhat.com>

On Wed, Oct 20, 2010 at 06:13:53PM +0200, Avi Kivity wrote:
>  On 10/20/2010 05:59 PM, Michael S. Tsirkin wrote:
> >>
> >>  One ugly way is to use two eventfds, one counting mask events, one
> >>  counting unmask events.  The difference is the value if the masked
> >>  bit.
> >>
> >>  Another option is to use
> >>  http://permalink.gmane.org/gmane.linux.kernel.commits.head/188038
> >>  which allows kvm to maintain a counter using eventfd.  The vfio
> >>  state machine then looks like:
> >>
> >>  interrupt:
> >>    if counter == 0 mask interrupts, set pending bit, wait for counter
> >>  to become 1
> >>    if counter == 1 forward it
> >>  counter becomes 1: unmask, forward interrupt if pending
> >
> >One issue is that this page has a ton of other info.
> >KVM would have to keep all that in kernel...
> 
> Or we'd make kvm an "accelerator" and pass through other accesses to
> userspace.  I don't like it because it's a blurry programming model.

Not sure I understand.

> At the very least it has to be documented very well.
> 
> -- 
> I have a truly marvellous patch that fixes the bug which this
> signature is too narrow to contain.

  reply	other threads:[~2010-10-20 17:18 UTC|newest]

Thread overview: 66+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-20  8:26 [PATCH 0/8][v2] MSI-X mask emulation support for assigned device Sheng Yang
2010-10-20  8:26 ` [PATCH 1/8] PCI: MSI: Move MSI-X entry definition to pci_regs.h Sheng Yang
2010-10-20 11:07   ` Matthew Wilcox
2010-10-20  8:26 ` [PATCH 2/8] irq: Export irq_to_desc() to modules Sheng Yang
2010-10-20  8:26 ` [PATCH 3/8] KVM: x86: Enable ENABLE_CAP capability for x86 Sheng Yang
2010-10-20  8:26 ` [PATCH 4/8] KVM: Move struct kvm_io_device to kvm_host.h Sheng Yang
2010-10-20  8:26 ` [PATCH 5/8] KVM: Add kvm_get_irq_routing_entry() func Sheng Yang
2010-10-20  8:53   ` Avi Kivity
2010-10-20  8:58     ` Sheng Yang
2010-10-20  9:13     ` Sheng Yang
2010-10-20  9:17       ` Sheng Yang
2010-10-20  9:32         ` Avi Kivity
2010-10-20  8:26 ` [PATCH 6/8] KVM: assigned dev: Preparation for mask support in userspace Sheng Yang
2010-10-20  9:30   ` Avi Kivity
2010-10-22 14:53   ` Marcelo Tosatti
2010-10-24 12:19     ` Sheng Yang
2010-10-24 12:23       ` Michael S. Tsirkin
2010-10-28  8:21         ` Sheng Yang
2010-10-20  8:26 ` [PATCH 7/8] KVM: assigned dev: Introduce io_device for MSI-X MMIO accessing Sheng Yang
2010-10-20  9:46   ` Avi Kivity
2010-10-20 10:33     ` Michael S. Tsirkin
2010-10-21  6:46     ` Sheng Yang
2010-10-21  9:27       ` Avi Kivity
2010-10-21  9:24         ` Michael S. Tsirkin
2010-10-21  9:47           ` Avi Kivity
2010-10-21 10:51             ` Michael S. Tsirkin
2010-10-20 22:35   ` Michael S. Tsirkin
2010-10-21  7:44     ` Sheng Yang
2010-10-20  8:26 ` [PATCH 8/8] KVM: Emulation MSI-X mask bits for assigned devices Sheng Yang
2010-10-20  9:49   ` Avi Kivity
2010-10-20 22:24   ` Michael S. Tsirkin
2010-10-21  8:30   ` Sheng Yang
2010-10-21  8:39     ` Michael S. Tsirkin
2010-10-22  4:42       ` Sheng Yang
2010-10-22 10:17         ` Michael S. Tsirkin
2010-10-22 13:30           ` Sheng Yang
2010-10-22 14:32             ` Michael S. Tsirkin
2010-10-20  9:51 ` [PATCH 0/8][v2] MSI-X mask emulation support for assigned device Avi Kivity
2010-10-20 10:44   ` Michael S. Tsirkin
2010-10-20 10:59     ` Avi Kivity
2010-10-20 13:43       ` Michael S. Tsirkin
2010-10-20 14:58         ` Alex Williamson
2010-10-20 14:58           ` Michael S. Tsirkin
2010-10-20 15:12             ` Alex Williamson
2010-10-20 15:17         ` Avi Kivity
2010-10-20 15:22           ` Alex Williamson
2010-10-20 15:26             ` Avi Kivity
2010-10-20 15:38               ` Alex Williamson
2010-10-20 14:47     ` Alex Williamson
2010-10-20 14:46       ` Michael S. Tsirkin
2010-10-20 15:07         ` Alex Williamson
2010-10-20 15:13           ` Michael S. Tsirkin
2010-10-20 20:13             ` Alex Williamson
2010-10-20 22:06               ` Michael S. Tsirkin
2010-10-20 15:23       ` Avi Kivity
2010-10-20 15:38         ` Alex Williamson
2010-10-20 15:54           ` Avi Kivity
2010-10-20 15:59             ` Michael S. Tsirkin
2010-10-20 16:13               ` Avi Kivity
2010-10-20 17:11                 ` Michael S. Tsirkin [this message]
2010-10-20 18:31               ` Alex Williamson
2010-10-21  7:41   ` Sheng Yang
2010-10-20 19:02 ` Marcelo Tosatti
2010-10-21  7:10   ` Sheng Yang
2010-10-21  8:21     ` Michael S. Tsirkin
2010-10-20 22:20 ` Michael S. Tsirkin

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20101020171139.GA24188@redhat.com \
    --to=mst@redhat.com \
    --cc=alex.williamson@redhat.com \
    --cc=avi@redhat.com \
    --cc=kvm@vger.kernel.org \
    --cc=mtosatti@redhat.com \
    --cc=sheng@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox