From: Paolo Bonzini <pbonzini@redhat.com>
To: "Kai Huang" <kai.huang@linux.intel.com>,
"Radim Krčmář" <rkrcmar@redhat.com>
Cc: gleb@kernel.org, linux@arm.linux.org.uk, kvm@vger.kernel.org
Subject: Re: [PATCH 6/6] KVM: VMX: Add PML support in VMX
Date: Fri, 06 Feb 2015 17:00:14 +0100 [thread overview]
Message-ID: <54D4E50E.2080508@redhat.com> (raw)
In-Reply-To: <54D30C5D.1000402@linux.intel.com>
On 05/02/2015 07:23, Kai Huang wrote:
>>>
>>> + /* PML is enabled/disabled in creating/destorying vcpu */
>>> + exec_control &= ~SECONDARY_EXEC_ENABLE_PML;
>> What is the harm of enabling it here?
>>
>> (SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES seems similar and does it.)
>
> Because the PML feature detection is unconditional (meaning
> SECONDARY_EXEC_ENABLE_PML is always in
> vmcs_config.cpu_based_2nd_exec_ctrl), but the PML buffer is only created
> when vcpu is created, and it is controlled by 'enable_pml' module
> parameter, if we always enable SECONDARY_EXEC_ENABLE_PML here, no PML
> buffer will be created if PML is disabled by 'enable_pml' parameter, so
> it's better to enable it along with creating PML buffer.
I guess this is the most interesting comment from Radim.
Paolo
prev parent reply other threads:[~2015-02-06 16:00 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-28 2:54 [PATCH 0/6] KVM: VMX: Page Modification Logging (PML) support Kai Huang
2015-01-28 2:54 ` [PATCH 1/6] KVM: Rename kvm_arch_mmu_write_protect_pt_masked to be more generic for log dirty Kai Huang
2015-01-28 2:54 ` [PATCH 2/6] KVM: MMU: Add mmu help functions to support PML Kai Huang
2015-02-03 17:34 ` Radim Krčmář
2015-02-05 5:59 ` Kai Huang
2015-02-05 14:51 ` Radim Krčmář
2015-01-28 2:54 ` [PATCH 3/6] KVM: MMU: Explicitly set D-bit for writable spte Kai Huang
2015-01-28 2:54 ` [PATCH 4/6] KVM: x86: Change parameter of kvm_mmu_slot_remove_write_access Kai Huang
2015-02-03 16:28 ` Radim Krčmář
2015-01-28 2:54 ` [PATCH 5/6] KVM: x86: Add new dirty logging kvm_x86_ops for PML Kai Huang
2015-02-03 15:53 ` Radim Krčmář
2015-02-05 6:29 ` Kai Huang
2015-02-05 14:52 ` Radim Krčmář
2015-01-28 2:54 ` [PATCH 6/6] KVM: VMX: Add PML support in VMX Kai Huang
2015-02-03 15:18 ` Radim Krčmář
2015-02-03 15:39 ` Paolo Bonzini
2015-02-03 16:02 ` Radim Krčmář
2015-02-05 6:23 ` Kai Huang
2015-02-05 15:04 ` Radim Krčmář
2015-02-06 0:22 ` Kai Huang
2015-02-06 0:28 ` Kai Huang
2015-02-06 16:00 ` Paolo Bonzini [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=54D4E50E.2080508@redhat.com \
--to=pbonzini@redhat.com \
--cc=gleb@kernel.org \
--cc=kai.huang@linux.intel.com \
--cc=kvm@vger.kernel.org \
--cc=linux@arm.linux.org.uk \
--cc=rkrcmar@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 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).