All of lore.kernel.org
 help / color / mirror / Atom feed
From: "Jan Beulich" <JBeulich@suse.com>
To: Mukesh Rathor <mukesh.rathor@oracle.com>
Cc: xen-devel <xen-devel@lists.xen.org>
Subject: Re: [PATCH 04/18] PVH xen: add params to read_segment_register
Date: Mon, 10 Jun 2013 09:01:37 +0100	[thread overview]
Message-ID: <51B5A40102000078000DC8D1@nat28.tlf.novell.com> (raw)
In-Reply-To: <20130607174537.0c3ce217@mantra.us.oracle.com>

>>> On 08.06.13 at 02:45, Mukesh Rathor <mukesh.rathor@oracle.com> wrote:
> On Fri, 07 Jun 2013 07:29:40 +0100
> "Jan Beulich" <JBeulich@suse.com> wrote:
> 
>> >>> On 07.06.13 at 03:43, Mukesh Rathor <mukesh.rathor@oracle.com>
>> >>> wrote:
>> > On Thu, 06 Jun 2013 07:48:49 +0100
>> > "Jan Beulich" <JBeulich@suse.com> wrote:
>> > 
>> >> >>> On 06.06.13 at 03:25, Mukesh Rathor <mukesh.rathor@oracle.com>
>> >> >>> wrote:
>> >> > On Fri, 31 May 2013 11:00:12 +0100
>> >> > "Jan Beulich" <JBeulich@suse.com> wrote:
>> >> > 
> ........ 
>> And anything we leave there should be optimized to hide latencies
>> between dependent instructions (the worst example here likely is
>> the CR2 read followed immediately by the intermediate register
>> getting written to memory, even though the control register read
>> could be done almost first thing in the handler).
>> 
>> One question though is why HVM code gets away without always
>> filling those fields, but PVH code doesn't. Could you say a word
>> on this?
> 
> Yeah, sure. The HVM IO instr emulation goes thru handle_mmio/handle_pio,
> and I've not looked at them since the PVH goes thru emulate_privileged_op(),
> which calls read_segment_register macro. The HVM functions do not call
> the read_segment_register macro. 

Then is there any reason why, rather than always reading all
selector registers, you couldn't defer the reading to when this
macro actually gets used? I'd assume there are going to be many
exits that don't need any of them...

Jan

  reply	other threads:[~2013-06-10  8:01 UTC|newest]

Thread overview: 80+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-05-25  1:25 [PATCH 00/18][V6]: PVH xen: version 6 patches Mukesh Rathor
2013-05-25  1:25 ` [PATCH 01/18] PVH xen: turn gdb_frames/gdt_ents into union Mukesh Rathor
2013-05-31  9:13   ` Jan Beulich
2013-05-25  1:25 ` [PATCH 02/18] PVH xen: add XENMEM_add_to_physmap_range Mukesh Rathor
2013-05-31  9:28   ` Jan Beulich
2013-05-31  9:38     ` Ian Campbell
2013-05-31 10:14       ` Jan Beulich
2013-05-31 10:40         ` Ian Campbell
2013-06-05  0:24         ` Mukesh Rathor
2013-06-05  0:31     ` Mukesh Rathor
2013-06-05  7:32       ` Jan Beulich
2013-06-05 20:41         ` Mukesh Rathor
2013-06-06  6:43           ` Jan Beulich
2013-06-06 22:19             ` Mukesh Rathor
2013-06-07  6:13               ` Jan Beulich
2013-06-07 20:46                 ` Mukesh Rathor
2013-06-07 15:08             ` Konrad Rzeszutek Wilk
2013-06-07 15:48               ` Jan Beulich
2013-05-25  1:25 ` [PATCH 03/18] PVH xen: create domctl_memory_mapping() function Mukesh Rathor
2013-05-31  9:46   ` Jan Beulich
2013-06-05  0:47     ` Mukesh Rathor
2013-06-05  7:34       ` Jan Beulich
2013-05-25  1:25 ` [PATCH 04/18] PVH xen: add params to read_segment_register Mukesh Rathor
2013-05-31 10:00   ` Jan Beulich
2013-06-06  1:25     ` Mukesh Rathor
2013-06-06  6:48       ` Jan Beulich
2013-06-07  1:43         ` Mukesh Rathor
2013-06-07  6:29           ` Jan Beulich
2013-06-08  0:45             ` Mukesh Rathor
2013-06-10  8:01               ` Jan Beulich [this message]
2013-06-10 23:10                 ` Mukesh Rathor
2013-05-25  1:25 ` [PATCH 05/18] PVH xen: vmx realted preparatory changes for PVH Mukesh Rathor
2013-05-25  1:25 ` [PATCH 06/18] PVH xen: Move e820 fields out of pv_domain struct Mukesh Rathor
2013-06-05 15:33   ` Konrad Rzeszutek Wilk
2013-05-25  1:25 ` [PATCH 07/18] PVH xen: Introduce PVH guest type Mukesh Rathor
2013-05-25  1:25 ` [PATCH 08/18] PVH xen: tools changes to create PVH domain Mukesh Rathor
2013-06-12 14:58   ` Ian Campbell
2013-06-15  0:14     ` Mukesh Rathor
2013-06-17 11:11       ` Ian Campbell
2013-07-30 23:47         ` Mukesh Rathor
2013-07-31 12:00           ` Ian Campbell
2013-08-01  2:02             ` Mukesh Rathor
2013-08-01  8:01               ` Ian Campbell
2013-08-02  1:12                 ` Mukesh Rathor
2013-08-29  1:51                 ` Mukesh Rathor
2013-08-29  9:01                   ` Ian Campbell
2013-08-30  0:45                     ` Mukesh Rathor
2013-08-30  9:56                       ` Ian Campbell
2013-08-29 11:13               ` George Dunlap
2013-08-29 11:29                 ` Ian Campbell
2013-08-30  1:24                   ` Mukesh Rathor
2013-08-30  9:53                     ` Ian Campbell
2013-08-30 10:22                       ` George Dunlap
2013-08-30 10:27                     ` George Dunlap
2013-08-29  0:14         ` Mukesh Rathor
2013-07-31  1:06     ` Mukesh Rathor
2013-07-31 11:32       ` Ian Campbell
2013-05-25  1:25 ` [PATCH 09/18] PVH xen: domain creation code changes Mukesh Rathor
2013-05-25  1:25 ` [PATCH 10/18] PVH xen: create PVH vmcs, and also initialization Mukesh Rathor
2013-05-25  1:25 ` [PATCH 11/18] PVH xen: create read_descriptor_sel() Mukesh Rathor
2013-05-25  1:25 ` [PATCH 12/18] PVH xen: support hypercalls for PVH Mukesh Rathor
2013-06-05 15:27   ` Konrad Rzeszutek Wilk
2013-05-25  1:25 ` [PATCH 13/18] PVH xen: introduce vmx_pvh.c Mukesh Rathor
2013-05-25  1:25 ` [PATCH 14/18] PVH xen: some misc changes like mtrr, intr, msi Mukesh Rathor
2013-05-25  1:25 ` [PATCH 15/18] PVH xen: hcall page initialize, create PVH guest type, etc Mukesh Rathor
2013-05-25  1:25 ` [PATCH 16/18] PVH xen: Miscellaneous changes Mukesh Rathor
2013-06-05 15:39   ` Konrad Rzeszutek Wilk
2013-05-25  1:25 ` [PATCH 17/18] PVH xen: Introduce p2m_map_foreign Mukesh Rathor
2013-05-25  1:25 ` [PATCH 18/18] PVH xen: Add and remove foreign pages Mukesh Rathor
2013-06-05 15:23 ` [PATCH 00/18][V6]: PVH xen: version 6 patches Konrad Rzeszutek Wilk
2013-06-05 15:25   ` George Dunlap
2013-06-05 15:36   ` Ian Campbell
2013-06-05 18:34     ` Konrad Rzeszutek Wilk
2013-06-05 20:51       ` Ian Campbell
2013-06-05 22:01         ` Mukesh Rathor
2013-06-06  8:46           ` Ian Campbell
2013-06-07 13:56             ` Konrad Rzeszutek Wilk
2013-06-06 10:08     ` George Dunlap
2013-06-05 17:14   ` Tim Deegan
2013-06-06  7:29     ` Jan Beulich

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=51B5A40102000078000DC8D1@nat28.tlf.novell.com \
    --to=jbeulich@suse.com \
    --cc=mukesh.rathor@oracle.com \
    --cc=xen-devel@lists.xen.org \
    /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.