All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Jan Beulich" <JBeulich@suse.com>
To: "Xuquan (Quan Xu)" <xuquan8@huawei.com>
Cc: "yang.zhang.wz@gmail.com" <yang.zhang.wz@gmail.com>,
	KevinTian <kevin.tian@intel.com>,
	"quan.xu0@gmail.com" <quan.xu0@gmail.com>,
	Andrew Cooper <andrew.cooper3@citrix.com>,
	"xen-devel@lists.xen.org" <xen-devel@lists.xen.org>,
	Jun Nakajima <jun.nakajima@intel.com>,
	ChaoGao <chao.gao@intel.com>
Subject: Re: [PATCH] x86/apicv: enhance posted-interrupt processing
Date: Fri, 24 Feb 2017 01:20:04 -0700	[thread overview]
Message-ID: <58AFFAC4020000780013D7AD@prv-mh.provo.novell.com> (raw)
In-Reply-To: <E0A769A898ADB6449596C41F51EF62C6AE85D2@SZXEMI506-MBX.china.huawei.com>

>>> On 24.02.17 at 09:02, <xuquan8@huawei.com> wrote:
> Another question, it 'd be the _main_gap_.. 
> If the pCPU runs __vmx_deliver_posted_interrupt() here, in a 
> hyperver-context,
> _iiuc_, all of vCPUs , waiting in the run queue, are scheduled out.. So the 
> 'current' is NULL, as there is no running vCPU..

Excuse me, but these are fundamentals. "current" can never be NULL.
If no guest vCPU is running, the idle vCPU for the pCPU would be.
And switching to hypervisor context _does not_ mean the current
vCPU changes. In particular, vlapic_set_irq() (which is a few call
stack layers up from __vmx_deliver_posted_interrupt()) can run in
various contexts afaics.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xen.org
https://lists.xen.org/xen-devel

      reply	other threads:[~2017-02-24  8:20 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-02-17  9:37 [PATCH] x86/apicv: enhance posted-interrupt processing Xuquan (Quan Xu)
2017-02-17  8:49 ` Chao Gao
2017-02-17 16:32   ` Jan Beulich
2017-02-20 11:25     ` Xuquan (Quan Xu)
2017-02-20  8:24       ` Chao Gao
2017-02-21  2:49         ` Xuquan (Quan Xu)
2017-02-21  3:07           ` Tian, Kevin
2017-02-21  4:11             ` Xuquan (Quan Xu)
2017-02-20 21:54               ` Chao Gao
2017-02-21  6:19                 ` Xuquan (Quan Xu)
2017-02-21  9:08                   ` Jan Beulich
2017-02-21  9:44               ` Tian, Kevin
2017-02-23  9:28     ` Xuquan (Quan Xu)
2017-02-23  9:59       ` Jan Beulich
2017-02-23 10:53         ` Xuquan (Quan Xu)
2017-02-23 11:01           ` Jan Beulich
2017-02-23 11:55             ` Xuquan (Quan Xu)
2017-02-23  8:37               ` Chao Gao
2017-02-27  8:00                 ` Xuquan (Quan Xu)
2017-02-23 12:26               ` Jan Beulich
2017-02-24  8:02                 ` Xuquan (Quan Xu)
2017-02-24  8:20                   ` Jan Beulich [this message]

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=58AFFAC4020000780013D7AD@prv-mh.provo.novell.com \
    --to=jbeulich@suse.com \
    --cc=andrew.cooper3@citrix.com \
    --cc=chao.gao@intel.com \
    --cc=jun.nakajima@intel.com \
    --cc=kevin.tian@intel.com \
    --cc=quan.xu0@gmail.com \
    --cc=xen-devel@lists.xen.org \
    --cc=xuquan8@huawei.com \
    --cc=yang.zhang.wz@gmail.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.