From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
To: Christopher Covington <cov@codeaurora.org>
Cc: Ian Campbell <Ian.Campbell@citrix.com>,
"xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>,
"linux@arm.linux.org.uk" <linux@arm.linux.org.uk>,
"konrad.wilk@oracle.com" <konrad.wilk@oracle.com>,
"marc.zyngier@arm.com" <marc.zyngier@arm.com>,
"catalin.marinas@arm.com" <catalin.marinas@arm.com>,
Stefano Stabellini <Stefano.Stabellini@eu.citrix.com>,
"will.deacon@arm.com" <will.deacon@arm.com>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"john.stultz@linaro.org" <john.stultz@linaro.org>,
"linux-arm-kernel@lists.infradead.org"
<linux-arm-kernel@lists.infradead.org>
Subject: Re: [Xen-devel] [PATCH 1/3] arm_arch_timer: introduce arch_timer_stolen_ticks
Date: Fri, 3 May 2013 11:43:23 +0100 [thread overview]
Message-ID: <alpine.DEB.2.02.1305031130210.5398@kaball.uk.xensource.com> (raw)
In-Reply-To: <5182DBA9.9080609@codeaurora.org>
On Thu, 2 May 2013, Christopher Covington wrote:
> > So the virtual timer should appear to have been running even while time
> > is being stolen and therefore stolen time needs to be accounted via some
> > other means.
>
> Something that's not currently obvious to me is that given that the stolen
> cycle accounting should be done, what makes the architected timer interrupt
> handler the ideal place to do it?
That is a good question and I would appreciate suggestions to improve
the patch.
Given that Xen x86 and ia64 does stolen time accounting from the timer
interrupt handler:
arch/x86/xen/time.c:xen_timer_interrupt
arch/ia64/kernel/time.c:timer_interrupt
and given that the arch_timer is the only timer used by Xen on ARM and
that it includes a virt_timer that is made on purpose to be used by
virtual machines, I thought that it might be a good place for it.
I also thought that doing it this way, KVM should be able to reuse the
same hook.
next prev parent reply other threads:[~2013-05-03 10:43 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-01 19:27 [PATCH 0/3] xen/arm: account for stolen ticks Stefano Stabellini
2013-05-01 19:27 ` [PATCH 1/3] arm_arch_timer: introduce arch_timer_stolen_ticks Stefano Stabellini
2013-05-01 20:36 ` Christopher Covington
2013-05-02 8:19 ` [Xen-devel] " Ian Campbell
2013-05-02 21:33 ` Christopher Covington
2013-05-03 10:43 ` Stefano Stabellini [this message]
2013-05-03 10:54 ` Marc Zyngier
2013-05-05 16:47 ` Stefano Stabellini
2013-05-06 14:55 ` Christopher Covington
2013-05-06 14:35 ` Konrad Rzeszutek Wilk
2013-05-07 16:17 ` Christopher Covington
2013-05-08 11:19 ` Stefano Stabellini
2013-05-08 11:48 ` Christopher Covington
2013-05-01 19:27 ` [PATCH 2/3] xen: move do_stolen_accounting to drivers/xen/time.c Stefano Stabellini
2013-05-02 8:19 ` [Xen-devel] " Ian Campbell
2013-05-02 18:49 ` Christopher Covington
2013-05-03 8:26 ` [Xen-devel] " Ian Campbell
2013-05-03 10:29 ` Stefano Stabellini
2013-05-01 19:27 ` [PATCH 3/3] xen/arm: account for stolen ticks Stefano Stabellini
2013-05-02 8:21 ` [Xen-devel] " Ian Campbell
2013-05-02 10:38 ` Stefano Stabellini
2013-05-02 10:48 ` Ian Campbell
2013-05-02 10:54 ` Stefano Stabellini
2013-05-02 11:02 ` Ian Campbell
2013-05-02 11:04 ` Stefano Stabellini
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=alpine.DEB.2.02.1305031130210.5398@kaball.uk.xensource.com \
--to=stefano.stabellini@eu.citrix.com \
--cc=Ian.Campbell@citrix.com \
--cc=catalin.marinas@arm.com \
--cc=cov@codeaurora.org \
--cc=john.stultz@linaro.org \
--cc=konrad.wilk@oracle.com \
--cc=linux-arm-kernel@lists.infradead.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=marc.zyngier@arm.com \
--cc=will.deacon@arm.com \
--cc=xen-devel@lists.xensource.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;
as well as URLs for NNTP newsgroup(s).