From: Avi Kivity <avi@redhat.com>
To: Jan Kiszka <jan.kiszka@siemens.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>,
Marcelo Tosatti <mtosatti@redhat.com>, kvm <kvm@vger.kernel.org>,
Eric Northup <digitaleric@google.com>
Subject: Re: [PATCH v4] KVM: Introduce direct MSI message injection for in-kernel irqchips
Date: Wed, 04 Apr 2012 14:50:11 +0300 [thread overview]
Message-ID: <4F7C3573.7080709@redhat.com> (raw)
In-Reply-To: <4F7C26F0.5090901@siemens.com>
On 04/04/2012 01:48 PM, Jan Kiszka wrote:
> >
> > I'm not so sure anymore. Sorry about the U turn, but remind me why? In
> > the long term it will be slower.
>
> Likely not measurably slower. If you look at a message through the arch
> glasses, you can usually spot the destination directly, specifically if
> a message targets a single processor - no need for hashing and table
> lookups in the common case.
Not on x86. The APIC ID is guest-provided. In x2apic mode it can be
quite large.
> In contrast, the maintenance costs for the current explicit route based
> model are significant as we see now.
>
You mean in amount of code in userspace? That doesn't get solved since
we need to keep compatibility.
--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.
next prev parent reply other threads:[~2012-04-04 11:50 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-28 17:47 [PATCH v2] KVM: Introduce direct MSI message injection for in-kernel irqchips Jan Kiszka
2012-03-28 17:52 ` Jan Kiszka
2012-03-28 19:58 ` Eric Northup
2012-03-28 20:21 ` Jan Kiszka
2012-03-29 15:39 ` Michael S. Tsirkin
2012-03-29 15:43 ` Jan Kiszka
2012-03-29 16:15 ` [PATCH v3] " Jan Kiszka
2012-03-29 16:46 ` Michael S. Tsirkin
2012-03-29 16:50 ` Jan Kiszka
2012-03-29 18:25 ` Jan Kiszka
2012-03-29 19:14 ` [PATCH v4] " Jan Kiszka
2012-03-29 19:41 ` Michael S. Tsirkin
2012-03-30 7:45 ` Jan Kiszka
2012-03-30 12:45 ` Michael S. Tsirkin
2012-04-03 16:27 ` Avi Kivity
2012-04-03 16:47 ` Jan Kiszka
2012-04-03 16:54 ` Avi Kivity
2012-04-03 17:24 ` Jan Kiszka
2012-04-04 8:47 ` Avi Kivity
2012-04-04 8:38 ` Michael S. Tsirkin
2012-04-04 8:44 ` Avi Kivity
2012-04-04 8:53 ` Michael S. Tsirkin
2012-04-04 9:22 ` Jan Kiszka
2012-04-04 9:36 ` Avi Kivity
2012-04-04 9:38 ` Jan Kiszka
2012-04-04 9:55 ` Avi Kivity
2012-04-04 10:48 ` Jan Kiszka
2012-04-04 11:50 ` Avi Kivity [this message]
2012-04-04 12:01 ` Jan Kiszka
2012-04-10 18:30 ` [PATCH] KVM: Introduce generic interrupt " Jan Kiszka
2012-04-23 14:44 ` Jan Kiszka
2012-04-23 15:17 ` Avi Kivity
2012-04-23 15:32 ` Avi Kivity
2012-04-23 15:55 ` Jan Kiszka
2012-04-24 11:54 ` Avi Kivity
2012-04-24 11:57 ` [PATCH v4] KVM: Introduce direct MSI message " Avi Kivity
2012-04-24 12:07 ` Jan Kiszka
2012-04-24 12:59 ` Avi Kivity
2012-04-24 13:24 ` Jan Kiszka
2012-04-11 22:10 ` [PATCH v3] " Marcelo Tosatti
2012-04-12 9:28 ` Jan Kiszka
2012-04-12 22:38 ` Marcelo Tosatti
2012-04-13 13:45 ` Jan Kiszka
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=4F7C3573.7080709@redhat.com \
--to=avi@redhat.com \
--cc=digitaleric@google.com \
--cc=jan.kiszka@siemens.com \
--cc=kvm@vger.kernel.org \
--cc=mst@redhat.com \
--cc=mtosatti@redhat.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.